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Cold hands &amp: Cold hands Causes – Mayo Clinic


Scleroderma – Symptoms and causes


Scleroderma (sklair-oh-DUR-muh) is a group of rare diseases that involve the hardening and tightening of the skin and connective tissues.

Scleroderma affects women more often than men and most commonly occurs between the ages of 30 and 50. While there is no cure for scleroderma, a variety of treatments can ease symptoms and improve quality of life.

There are many different types of scleroderma. In some people, scleroderma affects only the skin. But in many people, scleroderma also harms structures beyond the skin, such as blood vessels, internal organs and the digestive tract (systemic scleroderma). Signs and symptoms vary, depending on which type of scleroderma you have.

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Scleroderma’s signs and symptoms vary, depending on which parts of your body are affected:

  • Skin. Nearly everyone who has scleroderma experiences a hardening and tightening of patches of skin. These patches may be shaped like ovals or straight lines, or cover wide areas of the trunk and limbs. The number, location and size of the patches vary by type of scleroderma. Skin can appear shiny because it’s so tight, and movement of the affected area may be restricted.
  • Fingers or toes. One of the earliest signs of systemic scleroderma is Raynaud’s disease, which causes the small blood vessels in your fingers and toes to contract in response to cold temperatures or emotional distress. When this happens, your fingers or toes may turn blue or feel painful or numb. Raynaud’s disease also occurs in people who don’t have scleroderma.
  • Digestive system. Scleroderma can cause a variety of digestive symptoms, depending on which part of the digestive tract is affected. If the esophagus is affected, you might have heartburn or difficulty swallowing. If the intestines are affected, you might have cramps, bloating, diarrhea or constipation. Some people who have scleroderma may also have problems absorbing nutrients if their intestinal muscles aren’t properly moving food through the intestines.
  • Heart, lungs or kidneys. Scleroderma can affect the function of the heart, lungs or kidneys to varying degrees. These problems, if left untreated, can become life-threatening.


Scleroderma results from an overproduction and accumulation of collagen in body tissues. Collagen is a fibrous type of protein that makes up your body’s connective tissues, including your skin.

Doctors don’t know exactly what causes the abnormal collagen production to begin, but the body’s immune system appears to play a role. Most likely, scleroderma is caused by a combination of factors, including immune system problems, genetics and environmental triggers.

Risk factors

Anyone can get scleroderma, but it does occur much more often in women than in men. Several combined factors appear to influence the risk of developing scleroderma:

  • Genetics. People who have certain gene variations appear to be more likely to develop scleroderma. This may explain why a small number of scleroderma cases appear to run in families and why certain types of scleroderma are more common for certain ethnic groups. For example, Choctaw Native Americans are more likely to develop the type of scleroderma that affects internal organs.
  • Environmental triggers. Research suggests that, in some people, scleroderma symptoms may be triggered by exposure to certain viruses, medications or drugs. Repeated exposure — such as at work — to certain harmful substances or chemicals also may increase the risk of scleroderma.
  • Immune system problems. Scleroderma is believed to be an autoimmune disease. This means that it occurs in part because the body’s immune system begins to attack the connective tissues. In 15 to 20 percent of cases, a person who has scleroderma also has symptoms of another autoimmune disease, such as rheumatoid arthritis, lupus or Sjogren’s syndrome.


Scleroderma complications range from mild to severe and can affect your:

  • Fingertips. The variety of Raynaud’s disease that occurs with systemic scleroderma can be so severe that the restricted blood flow permanently damages the tissue at the fingertips, causing pits or skin sores. In some cases, the tissue on the fingertips may die and require amputation.
  • Lungs. Scarring of lung tissue can result in reduced lung function, which can impact your ability to breathe and tolerance for exercise. You may also develop high blood pressure in the arteries to your lungs.
  • Kidneys. When scleroderma affects your kidneys, you can develop elevated blood pressure and an increased level of protein in your urine. More-serious effects of kidney complications may include renal crisis, which involves a sudden increase in blood pressure and rapid kidney failure.
  • Heart. Scarring of heart tissue increases your risk of abnormal heartbeats and congestive heart failure, and can cause inflammation of the membranous sac surrounding your heart. Scleroderma can also raise the pressure on the right side of your heart and cause it to wear out.
  • Teeth. Severe tightening of facial skin can cause your mouth to become smaller and narrower, which may make it hard to brush your teeth or to even have them professionally cleaned. People who have scleroderma often don’t produce normal amounts of saliva, so the risk of dental decay increases even more.
  • Digestive system. Digestive problems associated with scleroderma can lead to heartburn and difficulty swallowing. It can also cause bouts of cramps, bloating, constipation or diarrhea.
  • Sexual function. Men who have scleroderma may experience erectile dysfunction. Scleroderma may also affect the sexual function of women by decreasing sexual lubrication and constricting the vaginal opening.

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Show references

  1. AskMayoExpert. Scleroderma. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2018.
  2. AskMayoExpert. Morphea. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2018.
  3. Systemic scleroderma. NIH U.S. National Library of Medicine Genetics Home Reference. https://ghr.nlm.nih.gov/condition/systemic-scleroderma. Accessed March 6, 2019.
  4. Scleroderma: In-depth. NIH National Institute of Arthritis and Musculoskeletal and Skin Diseases. https://www.niams.nih.gov/health-topics/scleroderma/advanced. Accessed March 6, 2019.
  5. Scleroderma. NIH National Center for Advancing Translational Science and Genetic and Rare Diseases Information Center. https://rarediseases.info.nih.gov/diseases/10308/scleroderma. Accessed March 6, 2019.
  6. Ferri FF. Scleroderma (systemic sclerosis). In: Ferri’s Clinical Advisor 2019. Philadelphia, Pa.: Elsevier; 2019. https://www.clinicalkey.com. Accessed March 6, 2019.
  7. James WD, et al. Connective tissue diseases. In: Andrews’ Diseases of the Skin: Clinical Dermatology. 13th ed. Edinburgh, U.K.: Elsevier; 2020. https://www.clinicalkey.com. Accessed March 6, 2019.
  8. Varga J. Risk factors for and possible causes of systemic sclerosis (scleroderma). https://www.uptodate.com/contents/search. Accessed March 21, 2019.
  9. Kellerman RD, et al. Connective tissue disorders. In: Conn’s Current Therapy 2019. Philadelphia, Pa.: Elsevier; 2019. https://www.clinicalkey.com. Accessed March 6, 2019.
  10. Coping with scleroderma. Scleroderma Foundation. https://www.scleroderma.org/site/SPageServer/?pagename=patients_coping. Accessed March 29, 2019.


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My Hands and Feet Are Always Cold — Should I Worry? – Cleveland Clinic

It’s a familiar scene. You turn up the thermostat; your partner turns it down. Some people struggle with feeling cold all the time — especially when it comes to their hands and feet.

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If you feel like your extremities are often cold, you may wonder if you should see a doctor. Here’s what you need to know.

When blood vessels constrict

“Cold hands and feet are a common complaint,” says vascular medicine specialist G. Jay Bishop, MD. “But generally, when this happens in young healthy people, it isn’t anything to worry about.”

It’s true that cold extremities can signal other, more serious problems, including peripheral artery disease (PAD); rheumatologic conditions, such as scleroderma, lupus and rheumatoid arthritis; or an underactive thyroid.

More often, though, they are signs of Raynaud’s phenomenon, a common, generally benign condition that causes the blood vessels in the fingers and toes to be overly constricted.

“Blood vessels constrict as a normal, healthy response to cold in order to preserve your core temperature and protect vital organs,” Dr. Bishop says. “However, in Raynaud’s, arteries in the fingers and toes constrict suddenly when exposed to cold, and the vessels slam shut.”

Besides the feeling of cold extremities, Raynaud’s causes temporary color changes. An affected finger may turn white (because the artery is closed), then it may turn blue or purple and, as it rewarms, it may turn red (because the artery is now wide open and dilated).

“These color changes can be quite alarming, but in people with the primary or benign form of Raynaud’s (that is, people with no underlying disease), they are harmless,” Dr. Bishop says.

What to watch for

While Raynaud’s is usually a harmless condition, it can also occur in people with underlying rheumatologic or vascular disease. In that case, the Raynaud’s may be associated with small pits or ulcerations in the fingers or toes that are difficult to heal.

“Any patients who have Raynaud’s and associated skin changes, including tightening or thickening of the skin, nail changes, or cracks and sores that don’t heal, should get checked out,” Dr. Bishop says.

It’s important to talk to your doctor if you have cold extremities and these symptoms:

  • Thickening or tightening of the skin.
  • Poorly healing sores or cracks on the fingertips or toes.
  • Fatigue.
  • Weight changes.
  • Fever.
  • Joint pain.
  • Rashes.

How to deal with feeling cold

If your doctor has ruled out any serious problems, keep in mind that the feeling of uncomfortably chilly fingers or toes often varies by the person. It’s generally based on personal comfort.

“Feeling cold feet or hands when you get into bed just may be who you are, especially if there are no other symptoms,” Dr. Bishop says.

Dr. Bishop recommends the following to help you cope:

  • Keep your tootsies toasty: Wear appropriate footwear and wool socks or layers of socks as needed.
  • Keep your hands warm, too: Even simple things, like wearing mittens instead of gloves, can help.
  • Consider your core temperature: Wear layered clothing, especially thin, warm layers to help preserve your core temperature (and which you can remove as needed).
  • Avoid caffeine and nicotine: These are vasoconstrictors that can exacerbate the effect of the cold.

Peripheral artery disease (PAD) in older adults

Cold hands and feet — especially in older people — also can be caused by PAD, which occurs when arteries become narrowed or blocked as plaque gradually forms inside the artery walls.

PAD can affect people age 50 or older with a history of diabetes or smoking, while anyone age 70 or older generally should be screened.

These symptoms can signal PAD:

  • Cold feet.
  • Leg cramping, heaviness, or pain when walking.
  • Hair loss on the shins.
  • Nail changes.
  • Painful sores on the feet or toes.

Know your body

When it comes to safeguarding your health, watch for new symptoms that persist, Dr. Bishop says. “What I tell my friends and family seeking medical advice is: You know your body best; you are the one who lives in it.”

If you have a shooting pain once for 20 seconds and it never comes back, you may never get to the bottom of it. But if you have shooting pain in your hands, feet or anywhere in your body for 20 seconds at a time — and it happens 10 times a day for two weeks — something is probably going on.

“Don’t be shy, that’s something you want to discuss with your doctor,” Dr. Bishop says.

Causes of Cold Hands and Feet and How to Deal with Them

Do your hands and feet get cold often? Then you’re not alone. Even outside wintertime and it isn’t cold out yet, getting cold hands and feet is actually a common occurrence for millions of people around the world.

If you find yourself getting cold hands all the time even though the weather isn’t cold, it could be a sign of health issues, and the most common ones include:

You have a circulation problem if blood flow to any part of your body (in this case the hands and feet) is reduced, and one of the primary symptoms of poor circulation is experiencing coldness in extremities. By itself, a circulation problem is not a condition. Rather, it is caused by another illness.

This disease can cause poor circulation in your body. It narrows your arteries and therefore limits blood circulation throughout your body, especially your extremities. Reynaud’s disease is prevalent among people who live in cold environments.

This is when your blood has limited red blood cells, which are required to provide oxygen to your body’s tissues. Along with fatigue and a general feeling of weakness, this condition also causes you to get cold hands and feet.

This refers to a group (Diabetes 1 and 2) of diseases in which your body doesn’t metabolise glucose properly, leading to high blood sugar levels. In both diabetes 1 and 2, symptoms include increased thirst and hunger as well as coldness or numbness in the hands and feet.

An autoimmune disease, lupus makes your immune system attack your own body such as your organs, joints, and blood cells. Although symptoms vary widely between those affected by the disease, getting cold hands and feet is typical. In some cases, the fingers and toes can turn blue or white.

How to deal with the cold hand & feet dilemma?

When it comes to cold hands and feet, no two persons will feel exactly the same. You may find it intolerable while others may not be bothered by it too much. This means ways of coping with the problem will also differ from person to person. However, here are some things you can do to try and deal with your own specific situation.

  • Keep your extremities warm.

You can fight the constant cold feeling in your hands and feet by making sure they are always wrapped. For your hands, wear gloves made of wool, fleece, cashmere, or leather. For your feet, you can wear thick socks or thermal socks, which are specifically designed to keep the feet warm.

  • Warm yourself up while sleeping.

Are your cold hands and feet getting in the way of your sleep? You can use an electric underblanket to keep yourself warm while you sleep. For maximum warmth, buy a blanket made of fleece, and look for one that has an additional foot warmer so that your feet can stay toasty throughout the night.

You can also buy yourself a portable heating product like a heating pad. This way, you have something to warm your hands and feet with when you’re at the office. Heating pads are lightweight, so you won’t have a problem bringing one with you.

  • Eat foods that promote healthy circulation.

If your cold hands and feet is caused by circulation problems, what you can do is eat foods that boost circulation. Your diet must consist of food such as fish, which improves circulation because it is rich in omega-3s, ginger, which stimulates blood flow, and garlic because it is an anticoagulant. You should also eat plenty of fruits and nuts.

Getting cold hands and feet is common and often nothing to worry about, but if your problem persists or if you think it’s getting worse, set up an appointment with your doctor immediately. Only they will be able to find out what exactly is causing the problem and determine the best course of treatment for you.


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Why My Hands and Feet Are Always Cold?

Home / Why My Hands and Feet Are Always Cold?

Having cold hands and feet even when not in a cold environment is quite common. Although uncomfortable, it is usually not a cause for concern as it could just be your system’s way of maintaining its natural body temperature.  

That being said, constantly experiencing cold hands and feet, particularly if accompanied by color changes, could be taken as a warning sign. It is possibly your body’s way of signaling that you may have a problem with your nerves and blood circulation. It may also mean that you are experiencing an issue with tissue damage harming your hands, fingers, feet or toes.

Different signs and symptoms to watch out for:

  • Changes in the color of the skin around your hands and feet (e.g. like blue or white skin)
  • Numbness or tingling
  • Open sores or blisters
  • Tightened or hardened skin

If you feel like your extremities are often cold, you may want to ask your doctor about it. Cold hands and feet are a common complaint, but when this happens to young, healthy people they have to take it more seriously. Cold extremities can signal other more dangerous problems, including Peripheral Artery Disease (PAD), rheumatologic conditions, scleroderma, lupus, rheumatoid arthritis or even possibly an under-active thyroid.

Raynaud’s disease

Possibly caused by cold hands and feet Raynaud’s disease, a generally benign condition, causes the blood vessels in the fingers and toes to overly constrict. In those rare cases, arteries in the fingers and toes constrict all of a sudden, and the vessels close down causing temporary color changes. Color changes are direct external visualization of what may be happening beneath the skin and thus they can be quite alarming. Nevertheless, for people with primary or benign forms of Raynaud’s or people without an underlying disease, color changes could also be harmless.

Although Raynaud’s is normally a harmless condition, it can also develop in people with underlying rheumatologic or vascular disease and may be connected with small pits or ulcerations in the fingers or toes that are difficult to heal.

Go and check with your doctor if you have cold extremities and symptoms such as: 

  • sores that heal poorly
  • cracked fingertips or toes
  • thickened or tightened skin
  • fatigue
  • weight differentiation
  • fever
  • joint pain or rashes

The sense of uncomfortably chilly fingers or toes often varies from person to person but can be addressed by:

  • Keeping your feet and hands warm by wearing wool socks, warm footwear and gloves.
  • Maintaining your overall body temperature by wearing layered clothing, which can be removed easily if needed. 
  • Avoiding caffeine and nicotine, since they can further aggravate the effect of the cold.

Older adults and peripheral artery disease

Cold hands and feet in older people can also be linked to PAD, resulting in their arteries becoming narrowed or blocked as plaque gradually builds inside the walls.

PAD usually affects people aged 50 or older with a history of smoking or diabetes. While anyone aged 70 or older should be screened regularly.

Why Are My Hands Always Cold?

The weather isn’t the only thing getting colder in the fall and winter — some people suffer from cold hands. This can be a normal response to cold temperatures, explained general practitioner Chun Tang, MD, from Pall Mall Medical. He added, “We automatically constrict blood vessels to save loss of heat and focus heat to central areas.” But cold hands could also signify a deeper issue.

Poor Circulation Can Cause Cold Hands

One common cause of cold hands is poor circulation, said Nicholas Pantaleo, MD, an internist and family medicine practitioner at Westmed Medical Group, said. This can stem from underlying medical conditions or simply genetics. He explained that poor circulation can be concerning since it may be a sign of other diseases, including diabetes or obesity. “In certain scenarios, the body will also decrease blood flow to the extremities, like your hands, to allow more blood flow to the more important organs like your brain, heart, and lungs,” he said, to maintain your body’s essential functions.

Stress Can Cause Cold Hands

“Cold hand surges are common when someone is experiencing a great deal of stress or anxiety,” added Dr. Tang. Stress and anxiety can manifest in physical ways throughout the body when they cause hormones like epinephrine or adrenaline to be released, explained Dr. Pantaleo. Stress can stimulate the sympathetic nervous system (your flight-or-fight response), which causes blood vessels to constrict in order to increase blood flow to the brain and vital organs, explained Leann Poston, MD, a licensed physician with Invigor Medical. Stress is seen as a threat to your body, and your body constricting the blood vessels is a defense mechanism to ensure you’ll stay alive.

Smoking and Drinking Can Cause Cold Hands

Smoking can also be a cause of cold hands, as it also constricts blood vessels. “Constricting blood vessels decreases blood flow to the hands and fingers, which can cause them to feel cold,” said Dr. Poston. Drinking alcohol can also cause cold hands, because it dilates blood vessels which slows circulation. “An initial warm feeling from dilated blood vessels changes to cold as blood moves more slowly through the body, and therefore doesn’t carry heat from muscles to other parts of the body,” she said.

High Cholesterol Can Cause Cold Hands

Having high cholesterol can also affect blood flow. If you have a buildup of cholesterol in your arteries caused by your diet or genetics, it affects the lumen inside (think of the space within a hollow body part, like a blood vessel). Eating an excess of foods high in saturated fat and cholesterol, including meat, eggs, dairy products, and even coconut oil, can raise your cholesterol levels, which can lead to coronary heart disease — and one symptom is numbness and coldness in the extremities.

Vitamin Deficiencies Can Cause Cold Hands

Dr. Pantaleo added that vitamin deficiencies can also cause cold hands. “A vitamin B12 deficiency can give you neurological symptoms, including the feeling of cold hands and feet, numbness, or tingling,” added physician Nancy Bono, DO, and chair of family medicine at New York Institute of Technology College of Osteopathic Medicine. Anemia, or low iron, can also be a culprit, so Dr. Pantaleo advises talking to your doctor about taking vitamin supplements such as B12 or iron to help improve this issue.

Raynaud’s Syndrome Can Cause Cold Hands

Another common health condition called Raynaud’s syndrome causes cold hands, said Dr. Poston. It’s a condition in which the blood vessels constrict too much, and the symptoms can vary from mild to severe. People will notice that their fingers turn white and then purple or blue, and eventually, the fingers turn red as blood flow is restored. Severe Raynaud’s can lead to tissue damage and breakdown if the fingers are not getting enough blood.

Underlying Health Conditions Can Cause Cold Hands

Dr. Tang said cold hands could also be a symptom of an underactive or slow thyroid, as well as diseases including Buerger’s disease, lupus, and scleroderma. Blood clots can also cause cold hands, and if you experience sudden, painful, cold white fingers or hands, he advised seeking immediate medical attention as it can lead to necrosis (death of cells) or gangrene (when substantial areas of tissue become necrotic).

How to Prevent Cold Hands

Maintaining a healthy weight, controlling your blood pressure, managing stress, eating a healthy diet, stopping cigarette and alcohol use, and protecting your hands when it’s cold outside are all good strategies to keep your hands warm, said Dr. Poston. If anemia or B12 deficiency is the issue, talk to your doctor about adjusting your diet or taking supplements.

If you’re stressed, find healthy ways to feel calmer, like doing relaxing yoga, reading, writing in a journal, talking to a therapist or friend, or doing something creative.

Exercising is great for maintaining a normal blood pressure and decreasing the risk of high cholesterol and type 2 diabetes, which will reduce the risk for blood-vessel damage, said Dr. Poston. Exercising regularly can also improve circulation.

How to Relieve Cold Hands

An obvious solution is to warm your hands up, either by putting on mittens, wrapping them in a blanket, or running them under warm water. If you experience cold hands because of poor circulation, Dr. Pantaleo said you can try swinging your arms in big circles to help recirculate blood to your extremities. Another option is to run up and down your stairs swinging your arms or to go for a brisk walk, as exercise can help get your blood flowing. “A person can also try to massage their hands or repeatedly clench and unclench their fists to increase blood flow to the hands,” said Dr. Pantaleo.

When to See Your Doctor About Cold Hands

Causes for concern may be one hand that is cold while the other is normal, or neurologic symptoms such as numbness and tingling in the hands, said Dr. Poston. If you’re experiencing other symptoms such as pain, shortness of breath, or extreme fatigue, that could point to more serious issues and you should consult your doctor. No matter what the cause, you don’t have to live with cold hands. It’s best to talk to your doctor so they can help you determine the cause so you can live more comfortably in a world of warmth!

Cold Hands? 7 Causes for Cold Hands, Diagnosis and Treatment

Cold hands are a common complaint in the vascular clinic. Many people feel that their hands are cold. Once colder days roll in this is more pronounced. In some cold hands are persistent. In others the hands become cold in response to various stimuli. Even for doctors this complaint can be confusing. This is because there are many causes for cold hands and making sense of them requires expertise. Some causes for cold hands are benign. Others are important to diagnose early. Some can be treated. Others can not. This article is all about the causes for cold hands.

Vascular causes for cold hands

Many reasons for cold hands are linked to the circulation. As a vascular medicine doctor I will always think of the following reasons when a patient asks me about cold hands:

Raynaud’s phenomenon

It is always surprising to me but may people have heard about Raynaud’s phenomenon. It is not very common, though. Maybe 5% of people had it in their lifetime. But when looking for causes for cold hands, Raynaud’s always comes up. The arteries of patients who have Raynaud’s overreact by constricting too much. This can be without an obvious cause or as an over-reaction to cold. When this happens the skin does not receive enough blood and there is a cold feeling. In typical Raynaud’s there are also skin color changes. The fingers turn white, then blue and finally red. It is often painful. Usually it affects only part of the fingers and not the whole hand.

Benign blue finger

Benign blue finger is a common cause for a blue, cold finger. True, technically this is not really one of the causes for cold hands. But it is so common that I thought I should write about it here. Basically a finger develops a blue discoloration. The blue color usually does not affect the tip of the finger. The cause is not known. On the other hand this passes on its own within several days.

Emboli as a cause of cold hands

Emboli can clog blood vessels. Lack of blood flow results in ischemia. The ischemia obviously results in cold hands. The area of the hand that is cold depends on the area that has been affected by the emboli. This could be just a part of a finger or the whole hand. Sources of emboli could be atherosclerosis, thrombus in an aneurysm, infection in the heart or tumor.


Acrocyanosis is just a fancy way of saying “blue fingers“. Some patients have over reactive arteries. When their hands are exposed to cold, the arteries constrict and the blood in them cannot move. Blood that isn’t flowing releases oxygen and turns blue. This is where the blue fingers come from. Treating cold hands that arise from acrocyanosis is easy. Just keep your hands warm with properly fitting gloves. Also, keep your core warm. Do this by consuming warm beverages, wearing warm cloths and wearing a hat.

Cold hands caused by mild acrocyanosis

Thoracic outlet syndrome

Thoracic outlet syndrome is kinking at the level of the shoulder. The artery, vein and/or nerves could be involved. Arterial thoracic outlet syndrome can result in aneurysm formation. An aneurysm is a dilated portion of the artery. A thrombus can form in this dilatation and can dislodge toward the hand. This may result in cold hands from lack of blood flow. The vein can also be compressed in the shoulder. This is called venous thoracic outlet syndrome. Venous thoracic outlet can result in an upper extremity DVT. The thrombosis can occlude the veins in the arm or shoulder and the hand and arm may swell. This swelling can compress the adjacent artery. If the artery is constricted the hand will be cold. That is why one of the causes for cold hands is actually a vein…

Neurological causes for cold hands

Problems with nerve endings are among the most common causes for cold hands. The cold sensation can actually be just that – a sensation. This means the nerves are feeling the cold even when it is only mild or not there at all.

You all probably know the most common neurological cause for cold hand. When someone is nervous the hands become cold and sweaty. Being nervous causes cold hands because the extra activity from the nerves also causes arteries to constricts. This can be felt as cold hands.

There are more “medical” neurological causes for cold hands. Thoracic outlet syndrome can actually compress the nerves in the shoulder. This can cause the hands to feel tingly. For some this feels cold. Another cause for nerve damage in the hands is diabetes. This is called diabetic neuropathy. Even though peripheral artery disease is more common in the legs than in the arms, it can happen. It can specifically occur in diabetics. So if things do not add up “neuropathy” may not be the right cause of the cold hands.

There are other causes of neuropathy that are not diabetes. Neuropathy can be caused by exposure to toxins or to injury. Many people who have had cold injury suffer from chronic cold hands. One of the most common causes for cold hands is previous cold injury. People who have had pernio may heal completely or have cold fingers later on.

Hormonal causes for cold hands

The thyroid is a gland located in the front of the neck. It regulates temperature and metabolism. If the thyroid is malfunctioning and is not secreting enough hormones, the metabolism may slow. This has several symptoms, but some of them are feeling cold all the time.

Testing for causes for cold hands

When patients have cold hands they often want to know why. Testing for the causes I have listed is not complicated, if you know how to interpret the results. First, you have to talk to the patient and examine them. The pattern of cold hands and the way they look is very helpful. Then objective testing can be added. First, there are pressure measurements. They are designed to assess for blood flow within the arms. These are similar to the ankle brachial index. Instead of the ankle pressure is measured at the wrist. Another option is a more complete test with pulse volume recordings. Flow in the fingers can be measured before and after cold exposure. This will help see if there is over-reaction to cold.

Cold hands without a diagnosis

Sometimes patients complain of cold hands but non of the reasons I have listed above cannot be found. In this case doctors will usually reassure the patient that whatever the reason is, it is probably not dangerous. They are probably right. When no causes for cold hands can be found, it usually means that there is nothing terribly wrong going on. Some people are just that much more sensitive to cold than others. For these people the usual recommendation is just to keep the hands warm.

Cold feet and cold hands

As much as cold hands are common, cold feet are common too. Cause for cold feet are similar but not identical to cause for cold hands. You can read more about the cold feet causes.

Cold Hands and Feet? | Foot Health

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What do you recommend for Raynaud’s disease?

Andrew Weil, M.D. | April 17, 2007

In those with Raynaud’s disease, the fingers and toes blanch and may become numb or painful on exposure to cold. The root problem is abnormal neurovascular reactivity – that is, the nerves controlling blood flow through small arteries become oversensitive, constricting vessels in peripheral areas of the body (fingers, toes, nose and earlobes) in temperatures that should not trigger this response. (Constriction of peripheral blood vessels is a protective response to conserve body heat in cold environments.)

This condition is most common among in women, between the ages of 15 and 40. Raynaud’s disease can occur on its own or it can accompany (and often precedes) serious autoimmune diseases such as lupus (systemic lupus erythematosus, also known as SLE) and scleroderma. It is weakly associated with developing in people who have with carpal tunnel syndrome, and it can also be triggered by some medications, including beta blockers used to treat high blood pressure, drugs for migraine that contain ergotamine, certain chemotherapy agents, and in over-the-counter cold remedies that cause blood vessels to constrict.

To prevent the symptoms of Raynaud’s, be sure to dress warmly during cold weather – wear thick socks, heavy gloves or mittens, a hat and scarf. If you smoke, stop – along with all the other health hazards smoking presents, nicotine constricts arteries in the extremities and can worsen Raynaud’s symptoms. Other stimulants including caffeine can also aggravate Raynaud’s.

My colleague, hypnotherapist Steve Gurgevich, Ph.D., notes that Raynaud’s disease is quite responsive to such mind/body methods as self-hypnosis and biofeedback training to “warm” the hands. Using these methods, you can quiet the reactivity of nerves and blood vessels in your hands and feet and allow more blood to flow in them. During attacks, running warm (not hot) water over your hands and feet may shorten the episode or reduce the severity. Try my relaxing breath to help relax the entire autonomic nervous system, including the nerves that control small arteries in the hands. And because stress can bring on attacks, relaxation training may help you avoid episodes. You also can try acupuncture; which may decrease the frequency of attacks.

In addition to addressing temperature changes and trying mind-body techniques, I recommend taking 100 mg of niacin (vitamin B3) twice a day. This helps dilate blood vessels. Ginkgo can also help increase circulation in the fingertips. Take 120 to 240 mg per day. Prescription medications, such as the calcium-channel blockers usually given to treat high blood pressure, are often used if other strategies aren’t sufficient. They can decrease the frequency and severity of attacks, but also have side effects – such as ankle swelling, headache and flushing.

Andrew Weil, M.D.

90,000 Cold hands signal serious illness

Cold hands not only bring discomfort, but also signal serious illness.

Medical center “Medakom” has collected for you all sorts of reasons for this symptom:

When the room is objectively cold, and in the summer you forget about cold hands, this is just a thermoregulation mechanism.

Thyroid hypofunction
Constantly cold hands, even in the heat, besides, slow heartbeat, fatigue, depression, unreasonable swelling and weight gain – go to your doctor and check your thyroid hormone.

Arterial hypotension
In simple terms – low blood pressure. Dizziness when changing position suddenly, tinnitus and cold hands due to lack of blood circulation. It is necessary with a doctor to find out what is the reason, and their mass: from pregnancy to heart and liver problems.

Deficiency of iron, B12, folic acid and possibly other trace elements, which leads to a decrease in hemoglobin and your organs and tissues are less supplied with oxygen.In addition, weakness, dizziness and heart palpitations. To identify a lack of hemoglobin, you need to take a general blood test; anemia – undergo a comprehensive examination.

Diabetes mellitus
Elevated blood sugar damages the nerves, resulting in numbness, paleness and constant coldness in the limbs.

High estrogen level
This reason makes the peripheral vessels more sensitive to cold. As a result, a woman’s body temperature changes throughout the menstrual cycle, as does her feeling of warmth and cold.

Autoimmune disease. The treatment is carried out by a group of doctors and the diagnosis is made not only on the basis of cold hands.

It constricts blood vessels and disrupts blood circulation.

Taking certain medications
If you find similar symptoms, you can contact the Medakom Medical Center and we will help you find out the cause of your cold hands.

Medical Center “Medakom”.We are trusted with invaluable children!

see also

See also

90,000 Cold hands and feet may indicate the presence of serious illnesses.

Many people complain that their hands and feet get cold at any time of the year. But they don’t take this problem seriously. After all, many of them do not know that this condition may indicate serious illnesses, Joinfo reports.

This is not a problem if the hands and feet are chilly during the cold season or when a person arrives in a cool room for a long period. But for many, the limbs are freezing in summer in intense heat or when they are in a warm room and regardless of any circumstances.

Raynaud’s Syndrome

This is one of the most common diseases, the symptoms of which are chilliness in the limbs. If initially this symptom is not taken too seriously, then in the event of complications such as numbness of the arms and legs, pain when exposed to cold, discoloration of the skin or, in severe cases, even the appearance of ulceration, a person should consult a family doctor, dermatologist or endocrinologist.

There are many reasons for this disease. Some of them are vascular neurosis, hormonal disorders, exposure to certain chemicals and drugs, rheumatoid arthritis, atherosclerosis and others. It develops mainly in young women and is characterized by spasm of small peripheral blood vessels and arteries. During an attack, the arms and legs acquire a white, sometimes bluish color, then turn red and all this is accompanied by severe pain.

Lack of certain minerals in the blood

Women who experience hormonal imbalances associated with the first menstrual period or during pregnancy or during menopause also face the problem of chilly hands and feet.This is due to the fact that at this time in the body there is a lack of iron, calcium or magnesium. And since minerals are necessary for transporting oxygen through the bloodstream, their deficiency negatively affects the entire blood circulation process, especially its peripheral part.


It is well known that hormones play a very important role in the functioning of organs and systems of the human body. One of their most important functions is the regulation of metabolism and temperature. When the thyroid gland malfunctions, the production of hormones decreases and a condition occurs called hypothyroidism.It is characterized by: constant chilliness in the limbs, dry skin, decreased blood pressure, brittle hair and constant fatigue.

Diabetes mellitus

Elevated blood glucose levels have a negative effect on the state of blood vessels, especially small peripheral ones. In diabetes mellitus, their thrombosis and destruction occurs. That is why people suffering from this serious illness often complain of cold extremities.

Chilliness in the legs is especially dangerous in this case, as this is a harbinger of the so-called diabetic foot.A condition in which the microcirculation of the lower extremities is completely disturbed, sensitivity gradually disappears and necrosis develops, and subsequently gangrene.


Adequate fluid intake contributes to normal metabolism, which helps the body generate heat and energy. In the case when a person drinks little water and gradually dehydrates, the body simply does not have enough resources to warm the limbs. The solution to the problem in this case is quite simple – to observe the drinking regime.

Obliterating endarteritis

This condition is typical mainly for an experienced smoker. As a result of the long-term effect of nicotine on the vessels, blood flow is disrupted and thrombosis of the lumen of the arteries occurs, as a result of which the limbs are constantly freezing. This especially affects the legs and subsequently everyone who has this bad habit experience severe pain when walking.

Anorexia or malnutrition

As with dehydration, inadequate food intake can cause metabolic disorders that promote thermoregulation.Moreover, overly thin people have practically no fatty layer, which helps the body to retain heat. Therefore, almost all of them are constantly very cold.

However, if the cause of excessive thinness is hyperthyroidism, that is, excessive production of thyroid hormones, such patients, on the contrary, experience a constant feeling of heat.

Vitamin B12 deficiency

Cobalamin deficiency can lead to permanent chilliness of the extremities, as the vitamin plays an essential role in the synthesis of red blood cells.The lack of red blood cells causes impaired blood circulation, and, accordingly, reduces the supply of internal fluid to the legs and arms. This condition is often common in vegetarians.

In addition to the above diseases, permanent chilliness of the extremities can be caused by: infectious-toxic shock, herniated intervertebral discs, post-stroke condition, electrolyte metabolism disorders, pregnancy, some diseases of peripheral nerves, worms and other parasites, acute allergic reaction, as well as age-related changes associated with metabolic disorders in the body.

Who should you contact?
Indeed, the number of diseases associated with chilliness of the arms and legs is very large. The first step that needs to be taken is to visit a doctor who will give a referral for general blood and urine tests, tests for blood sugar levels, kidney function, screening for hepatitis B and C, hormonal tests. In the event that the answers do not correspond to the norm, he will recommend specialists who should be consulted.

In some cases, the doctor may recommend to do a tomography, X-ray of the lungs or cervical spine, and examine the arterial circulation (plethysmography). The examination is carried out in stages, depending on the symptoms and accompanying signs.

How to relieve the condition?
Before a correct diagnosis is made, there are steps that each person can take to reduce the severity of their symptoms. First of all, smokers need to get rid of their bad habit, as well as those suffering from alcohol addiction to stop drinking.Always remember to wear gloves in cool weather.

In addition, stressful situations must be avoided. It will be useful to take vitamin complexes specially designed for people suffering from anemia or deficiency of minerals and vitamin B12. Taking fish oil, which contains omega-3s, calcium, magnesium and iron, is extremely beneficial.

As with any health problem, attention should be paid to nutrition. In particular, people with atherosclerosis should avoid animal fats, sweets, alcohol and excess salt intake.To relieve the condition, you can use ointments based on arnica, chestnut, coffee, pepper, because they help to activate blood circulation

Among other natural remedies that can effectively help with this problem, tea with rosemary can be noted. In turn, nutritionists recommend a diet rich in pumpkin seeds and nuts, melons. And also regular consumption of spinach, as it is a rich source of iron. During cooking, salt should be replaced with hot spices, and sodium itself should be avoided as much as possible.

Equally important is the observance of the drinking regime, that is, the use of at least 2 liters of water daily. And also full sleep for about 7 hours every night, since chronic lack of sleep also reduces metabolism and provokes a violation of the blood supply to the peripheral vessels of the extremities.

Cold hands as a symptom | GBUZ JSC Magdagachinskaya hospital

If your hands and feet freeze in a cold room or on the street, and in a warm place you forget about this problem – congratulations, your thermoregulation mechanism works great: the body tries to keep warm for the internal organs and reduces blood flow in the extremities, which leads to cool them down!

But if you begin to notice that you are constantly chilly, regardless of the ambient temperature, if the limbs remain cold even in a warm room, you should not ignore this manifestation of the body, you should pay attention to the problem, find the cause.

Possible causes:

Thyroid hypofunction. In this condition, the thyroid gland does not work at full strength, which leads to a slowdown in metabolic processes. Hence, there is a constant feeling of coldness.

Anemia. A decrease in the level of hemoglobin entails a deterioration in the process of supplying internal organs and tissues with oxygen. Due to insufficient blood supply, the body saves resources (as is the case with thermoregulation) and therefore the limbs become cold.

Arterial hypotension or low blood pressure. If you have persistent low blood pressure, then most likely you are already familiar with this symptom due to insufficient blood circulation. However, if the drop in pressure has become sharp and frequent, you should consult a doctor to find out the reason.

Raynaud’s syndrome. A very rare disease. It manifests itself constantly with cold extremities, and when it freezes, the fingers turn white or blue and hurt due to severe vasoconstriction.When warmed up, the fingers turn red. The disease is not dangerous, but it increases the risk of frostbite.

Diabetes mellitus. Increased blood sugar gradually destroys nerve cells. This results in numb, pale and persistently cold limbs. Most often, the legs suffer from this problem.

High estrogen level. In this case, more women are affected than men. The increase in estrogen makes the peripheral vessels more sensitive to cold.As a result, a woman’s body temperature changes throughout the menstrual cycle, as does her feeling of cold and warmth.

Systemic lupus erythematosus. Cold hands and feet are one of the manifestations of this autoimmune disease. Blood vessels can be attacked by the immune system, which leads to Raynaud’s syndrome, which was mentioned above.

Smoking. It is a well-known fact that smoking constricts blood vessels, thereby impairing blood circulation.Therefore, heavy smokers often complain of cold hands and feet.

Of course, cold hands and feet are not the only symptom of these diseases, but this does not mean that you should not pay attention to it. If this problem began to bother you, immediately contact your local doctor with a compulsory medical insurance policy! And remember, disease is easier to prevent than to cure!

If you are insured with SOGAZ-Med and you have any questions related to the receipt of medical care in the compulsory medical insurance system or the quality of medical services, please contact SOGAZ-Med by calling the 24-hour contact center phone number 8-800-100-07-02 (call within Russia is free).Detailed information on the website www.sogaz-med.ru .

Company information:

The SOGAZ-Med insurance company has been operating since 1998. The SOGAZ-Med regional network ranks 1st among medical insurance organizations in terms of the number of regions of presence, with more than 1,120 subdivisions in 56 constituent entities of the Russian Federation and the city of Baikonur. The number of insured is over 42 million people. SOGAZ-Med carries out activities related to compulsory medical insurance: it controls the quality of services provided to insured persons while receiving medical assistance in the compulsory medical insurance system, protects the rights of insured citizens, and restores violated rights of citizens in pre-trial and judicial procedures.In 2020, the Expert RA rating agency confirmed the rating of the reliability and quality of services of the SOGAZ-Med insurance company at the A ++ level (the highest level of reliability and quality of services in the framework of the MHI program according to the applicable scale). For several years now, SOGAZ-Med has been awarded this high level of assessment.

Non-canon tube amplifier / Habr

Good day, everyone!

Once, on a cold dreary evening, I was reading an article about a high-quality class D amplifier from Aliexpress.And I got the idea to tell you about my DIY craft. And now our hands have reached. Below is a worklog on making the next-how-much-already-possible tube (and not only) amplifier. The article is replete with frivolity and Petrosyanism, but still you can find a couple of, perhaps, useful schemes here.


  1. WARNING traffic! Lots of pictures.
  2. CAUTION! Hazardous voltages are used in the circuits shown. Reproducing the above schemes, you do it at your own peril and risk.The author is not responsible for the consequences resulting from the duplication of both the entire device and its individual parts.

I’ll clarify right away:

  • The amplifier is not Hi-End or Hi-Fi, because not a single gram of powder paint was used in its production!
  • I am not an adherent of the confession of a spiritual, heat lamp sound. But the lamps glow so cool …
  • Possible questions from the class “Why bother?” prepared answer “Because a hobby.”

I repeat: the whole project was started not for the sake of obtaining a “tube” sound, but because of the special aesthetics of well-made tube amplifiers. It was aesthetics that became the basis for the overwhelming majority of the problems that arose. She also determined the final cost, which quite significantly exceeded the original budget: piece production (in this case, read prototyping) always turns out to be much more expensive than it might seem at first glance. I also want to note right away that the task was to develop an amplifier from scratch, not reducing everything to the banal “I bought a set on the Internet, soldered it and inserted it into a shoebox.”In the end, this is still a DIY project, there must be a challenge, suffering and a desire to throw everything to hell! However, you shouldn’t go to extremes either. In theory, you can do everything completely without using purchased products, but in this case you need the appropriate tools (read machines), otherwise the result may, to put it mildly, disappoint.

The only question is the ultimate goal. So, let’s begin!

The play in four acts. Heroic epic

Act one. Planning

Good planning is a guarantee of fewer iterations from “how could I have done this at all” to “it could have been better, but it will do just that.”The amplifier was originally conceived to replace standard computer speakers. Let’s be honest, watching vidyashek with cute cats under a blanket through a warm, tube amplifier, of course, can complement the picture, but it is not rational. Which leads to a completely natural idea to throw in an amplifier on good old solid-state semiconductors. And according to his own mood, Monsieur will be free to choose which of the amplifiers to use for listening to Dire Straits, and which for the 2Pac.As a result, the circuitry has become somewhat more complicated, but we remember about the challenge, tests and all this. The result is 4 printed circuit boards: a power supply, a tube amplifier, a solid-state amplifier, and a breakout board. Everything seems to be simple, let’s move on.

Second act. Design

Actually for what all the fuss. My visual talents are limited to conventionally straight lines exclusively on checkered paper. But I had an engineering background, so armed with CAD and a lot of patience, I slowly and with a creak visualized what I would like to get in the end.And yes, do not be surprised that the case design comes first, and not the circuitry, as is usually the case.

A little about the case itself and the “classic” look of the tube amplifier. I never understood the passion to expose all the electronics outside. Lamps, yes, they are beautiful, hot and putting them outside (even sacrificing a little noise immunity) is not such a bad idea, but screwing huge transformers with a W-shaped core ON the top cover of the case is a rather dubious decision. Some go even further: and, in addition to all of the above, put a bank of capacitors on top! The finish! It seems that you are not looking at a finished device, but at a kind of breadboard.Although, in taste and color, all markers are different …

I settled on using an anodized and brushed aluminum body with decorative mahogany (jarrah) overlays. Also, to reduce the size, it was decided to use toroidal transformers. The metal base of the case, the knobs of the switches, the legs were purchased from Aliexpress, the rest were planned to be made on our own. Almost every detail was drawn, after which everything fell into place beautifully …

And then the body was sent.Needless to say, the dimensions given by the Chinese in the documentation have a rather mediocre relationship to the real device. I always wondered: “Is everything done by eye in China?” What is the problem with attaching the correct drawings, according to which you are manufacturing the part? I understand that if they hadn’t been attached at all, no, they were there, but not correct! Apparently protection from competitors.

When the approximate dimensions of the case became clear, it was the turn of the circuitry. Why exactly in this sequence? For the sake of compactness.Weighing more than 10 kg, dimensions are 40x30x20 cm (with all decorative elements). Inside it is quite plump (see photo below). As a result, the size of the components on the boards, as well as the dimensions of the boards themselves, are of great importance. PCB dimensions, component heights, element placement, everything was selected, drawn in 3D and checked on the assembly. If the details touch each other, we go back two steps, and so on until the victorious. The first couple of times it’s even amusing: I’m such a fine fellow, I checked everything, avoided problems.Somewhere after the third time, the idea comes to drink to the health of parametric CAD developers. I strongly recommend everyone who is not yet to learn the basics of any of the systems, and not to neglect the modeling stage, even for home crafts. From a large one that I identified: it turned out that a 90 W mains transformer, which initially stood up perfectly, does not fit into the case (hello to Chinese drawings). I had to replace it with two 60 W each (these are the ones inside on the side walls).

Third act.Circuitry

I have never dealt with lamp technology, and that says it all. Technically, I can draw analogies with transistors and, in general, everything is quite simple, but not without nuances. After spending several days searching in the vastness of the network, I settled on an option using single-ended output stages on 6V6GT tubes. If someone is very interested in comparing different options for output stages, as well as different classes of amplifiers in general, I advise you to read


. I chose what I chose and I don’t want to overload the text with unnecessary information.

But I can’t help but clarify that single-ended class A amplifiers have a special warmth and depth of sound, especially at medium frequencies … tfu, I almost did not believe myself! But seriously: in addition to the lack of “notch” type distortion at the output stage, they are just warm. No, they are really very warm, because the efficiency of class A amplifiers does not exceed 10-15%, the rest is spent on heating the room. The calculated power of my amplifier is about 4.5 watts. I used this scheme as a basis, but made some adjustments.And, in addition to luminousness, of course, there is a luminescent indicator of the “magic eye” type. Looks very cute.

From this moment, a selective heresy begins, according to the views of true witnesses of the lamp sound, I strongly recommend the followers of this faith to flip through the text and just stick to the photos of the result. I warned!

To begin with, I do not like the classic approach to building tube amplifiers, which implies the use of exclusively passive components (resistors, capacitors, transformers), with the exception of the tubes themselves.Solid-state semiconductor devices have a big advantage (one of) over lamps – a much smaller spread of characteristics. Two lamps of the same name, even produced in the same batch, can differ significantly. Because of this, it can often be seen that output stage tubes are sold as matched pairs with similar characteristics. But where is the guarantee that after warming up they will remain the same? And after a certain hour of work? There are too many uncertainties. At the same time, semiconductor devices can be used to level the parameter spread.For example, instead of a standard resistor that sets the cathode current, you can use a current source on the LM317A. At the same time, this will not affect the sound path in any way, but the current will not depend on the parameters of the lamp. On the Internet, you can find options for such solutions, so mine is not particularly original.

The solid-state amplifier is even less remarkable: a standard STA540 chip with minimal piping. Amplifier class AB, for everyday use in conjunction with a computer – the most it.Additionally, it is possible to solder an active filter on the board and use it as a 2.1 system, that is, with a subwoofer. Not used in this variant.

Finally, the funniest thing is the power source. There was complete hardcore here.
Going against the dogma, I decided not only not to use the kenotrons loved by all lamp-lamps, but also, in principle, to abandon the linear power source! Switching power supplies are better, both in terms of efficiency and size.Further, the design went on a completely curved path. The choice of the PWM controller microcircuit and the flyback transformer was chosen according to the principle “try for free, why not?” The fact is that the controller and specially designed transformers can be ordered as samples completely free of charge (with registration, but without SMS!). This is not the best option, because there are more standard, proven controllers, and therefore a bunch of time-tested circuits. Below is a diagram of power supplies for tube (+300 V, +285 V, +6 V) and solid-state (+18 V) amplifiers.

The voltage from the step-down network transformers is rectified and then fed to the pulse converters. An experienced power supply designer might ask: why such perversions? Indeed, it would be possible to immediately rectify the mains voltage and put it on the converters, but I wanted to make a galvanic isolation from the mains. In the given version of the circuit there are no inductive filters for the outputs of the pulse sources (added by volumetric wiring).The jamb will be fixed in the next version.

Looking ahead, I will say that setting up the power supply was the most problematic of all the debugging work. This was partly due to the fact that the last time I was seriously involved in circuitry 6 years ago. But in the end, partly after dancing with a tambourine, partly, after asking stupid questions on thematic forums, I found a solution to the problems that had arisen and everything started!

Act fourth, last. Build

I ordered printed circuit boards from the Chinese at FirstPCB.The quality is acceptable: silk-screen printing has different thicknesses, the holes are slightly offset from the center of the contact pads. Overall, not bad considering the cost.

The minimum order is 5 pieces, so now I have a little more of them than what I need …

Boards after unpacking:

and soldered:

Amplifier test without case:

Well, where without magic eye:

Further corpus. The fact is that in our area, for some reason unknown to me, it is very difficult to order the processing of a part made of wood on a 5-axis CNC machine.They ask either fabulously expensive, or they don’t do it at all. And this despite the fact that, being a little in the subject, I designed with minimization of complexity. The Chinese did not help either: having sent a request to 8 firms, they received a positive response from only two. The rest of the parties less than 10 pieces are not interested, although their sites talk about prototyping services. But the other two also decided not to limit themselves in price, and on top of that, they asked for photos and a full drawing of the device! I wonder why they need it …

As a result, they had to simplify the details to almost 2.5D and milled on a local CNC machine. On the one hand, it turned out, relative to the others, not expensive. On the other hand, if we add to this all those square kilometers of rough sandpaper that I had to lime, correcting what these guys did … Seriously, the feeling is that they are not familiar with the technology in principle and used standard modes for chipboard, from which they grind 99% of their orders. But I’m not greedy, I additionally gave them a weighty piece of material to select the parameters!

More sandpaper to the god of sandpaper:

Special thanks to them for first promising to make holes in aluminum parts, and then saying that they had never done this before and were afraid to break the machine.Iron logic, even to argue is useless. As a result, the project turned from a stress-free screwdriver assembly of ordered parts into a hardcore DIY, because working with metal, albeit with soft aluminum, in a small apartment without special equipment makes you experience existential horror. At first. And then you reach the stage of acceptance, take a hand drill, a hacksaw for metal, and stubbornly move towards your intended goal.

Next, a few pictures with the assembly stages for hikporn lovers:


Finally, all the parts are ready and sanded to 400 grit:

By the way, in the process of sanding, in order to protect the lungs and carpet from wood dust , a unique rig from a cardboard box and sleeves from an old shirt was used! A kind of home glovebox.

Then everything was covered with 4 layers of varnish:

Well, then the gradual assembly went:

As I mentioned earlier, boards and network transformers are attached to the side walls

No jungle of wires, only braids, only beauty (the wires from the lamps were subsequently shortened):

The markings on the back panel were laser engraved:

complete without device and with the tube amplifier board:

Final testing after assembly (the cat is warming up near the lamp, everything is according to the canon):

Polished copper pipes, without them there is no way:

Below is the final photo shoot of the fully assembled device.There is also a clock on gas-discharge indicators, which actually squares the warmth and luminosity of the entire scene!

Final photo session


The entire project, from concept to implementation, took about six months. Behind the scenes, there were a few analysis and collection of the amplifier in order to make changes and improvements, but this can be done endlessly. In general, I am satisfied with the result. As planned, in most cases a solid-state amplifier is used and only occasionally a tube is started, mainly for comparison.However, the main goal – to revive your old hobby and dig deeper into electronics, has been fully achieved! Write your questions and comments in the comments.

Have a great weekend everyone!

individual feature or alarm?

There are undoubtedly people around you whose hands and feet are always cold, even in a warm room or in hot weather. What is this – a feature of the body or a symptom of a disease?

The reasons for the constant coldness of the hands and feet are numerous:

  1. In women, this feature is more common than in men.Obviously, the reason is the weakness of thermoregulation, due to the physiology of the female body – a constant change in hormonal levels.
  2. Tall, thin, asthenic build people can also suffer from insufficient thermoregulation.
    People of age are constantly chilly, which is associated with the slowdown of all body processes, including thermoregulation.
  3. Children are also sensitive to external temperature, especially under one year old. Their thermoregulation is not yet stable, so they easily overcool and overheat.
  4. Cold hands and feet can be caused by a strict diet. The body receives energy from food, and in the case of a lack of calories in food, they are not enough to maintain a normal body temperature.
  5. Cold extremities can also be caused by circulatory disorders due to vascular spasm associated with stress, smoking, or wearing excessively pressured clothing and accessories.
  6. With iron deficiency anemia, characterized by a lack of hemoglobin and oxygen starvation of body tissues, heat generation is reduced.As a result, the legs freeze, the hands are cold, the patient complains of rapid fatigue, general weakness, dizziness, drowsiness, and tinnitus.
  7. Very often the cause of cold hands and feet is vegetative-vascular dystonia. This is a complex of symptoms that occurs as a result of the uncoordinated effects of the sympathetic and parasympathetic parts of the autonomic nervous system. Vegeto-vascular dystonia is also characterized by a number of other unpleasant phenomena, in particular, dizziness, sudden changes in blood pressure, palpitations, pain in the region of the heart (in the absence of cardiac pathology).
  8. Deficiency of thyroid hormones (thyroxine) – hypothyroidism, slows down all processes in the body, including heat exchange.
  9. With low thyroid hormone levels, other symptoms are also observed, including easy fatigue, memory impairment, weight gain, dry skin, brittle nails, constipation, etc.
  10. Cold hands and feet, as well as severe sweating, weakness, low body temperature may indicate the presence of arterial hypotension – low blood pressure.
  11. Obliterating endarteritis (smoker’s disease) – a violation of the patency of the vessels of the lower extremities – begins with cold feet, but can end with gangrene. Other manifestations – numbness of the feet, pain and leg cramps, trophic ulcers, necrosis.
  12. One of the manifestations of diabetes mellitus is a violation of blood supply, first – in the capillaries, and then in large vessels.
  13. Not surprisingly, those with this condition have cold hands and especially feet. Legs are affected more often, up to the development of a “diabetic foot”, which is a serious complication and threatens the development of gangrene and amputation.
  14. Cold hands are a symptom of an uncommon disease called Raynaud’s syndrome. It manifests itself as numbness, cramps, and loss of sensitivity in the fingers.
  15. Heart failure and its associated lack of blood supply also cause cold hands and feet.
  16. Osteochondrosis of the spine – dystrophic changes in the vertebrae and their deformity – can cause disruption of blood supply and lead to cold hands and feet.

Cold hands and feet can be the result of both weak thermoregulation or physiological reasons (hormonal fluctuations in women, slowing metabolic processes in the elderly, constitutional features), and serious pathologies.If, in addition to eternally cold extremities, there are no other formidable symptoms, blood pressure is within normal limits and a strict diet is not followed, then it may be necessary to check the level of hemoglobin and glucose in the blood, as well as the level of thyroid hormones.

Kapous Professional Color Enhancer – “The eyes are afraid, but the hands are doing!) Experiments with mixons … I wanted to get rid of the redhead, I was afraid of the green!) And what happened in the photo” Before “and” After “”


If you have never used mixtons, but really want to try them, then this review is for you … Because I, too, have never added mixtons when dyeing hair … but I decided … decided! )

I dilettante t, who just wants to share his experience!)

I will not teach anything … And I have no right! Just tell you about my experiment with hair!)

Ash – Enhancer 01, Kapous Studio hair color cream.

I learned about mixtons from the reviews on Kapous paint, which I read just dozens or even hundreds when I was looking for products for dyeing my hair. In the reviews of professional paint every now and then some unfamiliar to me “ mixtons ” were mentioned.

Having become interested, I learned that the manufacturer Kapous has its own mixtons or color enhancers

Mikston is such a hair dye, but it is not used as an independent tool, but is added to another paint to enhance shade or to neutralize unwanted tones.Mikston is a very intense pigment.

Advice from the vastness of the Internet…

To neutralize any shade, use the opposite one. For example, coppery red is neutralized by blue, red by green, green by red, yellow by purple, etc.

Usually they are used in salons, hairdressing professional specialists to obtain a better result. But since the paint is sold in any shop prof.cosmetics, any brave girl can feel like a mega a cool colorist!)

My hair is dyed, I used Kapous hair dye cream 7.23

I needed to neutralize the red-haired color , which after leaving the beige color remained bright tint on my hair !!!

The paint is washed off evenly, and quite firmly took on my hair.

The only thing is that is a bright reddish shade I’m pretty fed up with … Not that it doesn’t suit me … just THE SOUL DEMANDS CHANGE!) , as soon as the main pigment is washed out from the hair …

As a result, a month after dyeing, my hair was left with a beige tone with orange tints, which, in bright light, generally looks like some kind of bright red !…

With the last photos, I wanted to convey how the hair looks in daylight and natural light …

If you are interested in a blonde dog with a photo … I can suggest you look here and read about it!)

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So with this base I decided to dye my hair in ashy shade by choosing Kapous cream hair color 8.1 with hyaluronic acid … to enhance the ash, I decided to try adding a color enhancer Kapus-01 ash

About the amplifier itself …

✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ ❃

Externally, the amplifier is generally the same as a tube of paint … a 100 ml tube of turquoise color. You can’t tell at all!)

Only the inscription on the tube allows us to distinguish between these two compositions! Externally absolutely identical!

Sold only in professional cosmetics stores!

How to calculate the amount of color enhancer!)

11 – depth of tone = amount of mixton in centimeters per 30 g of paint.

That is, when staining in dark blond, we take 30 g of medium blond – this is 6 tones and apply the rule:

11-6 = 5, that is, you need 5 cm of the required mixton. Accordingly, if you need 60 g of paint, then there is more mixton.

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♥♥♥ With this staining, I added 4 cm mixton . I used the proofreader for the first time , so I took it to a minimum…

Focusing on the “rule of ten”, but using the minimum amount! I experimented, but with care not to get unexpected results!)

What did I use the mikston for? To help the paint cope with reddish shades, and give a matte ash shade! Those. to enhance the ashy shade, and neutralize the orange!

Oxide chose – 3%, t of the same manufacturer.

The volume of the developing emulsion is 150 ml.

✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ ❃ The oxide is diluted one to one and a half! ✾ ✿ ❀ ❁ ❂ ❃✾ ✿

I weighed everything on these scales! Everything turns out very accurately, to a gram!)

✾ ✿ ❀ ❁ ❂ ❃ The paint with oxide and corrector was stirred with a brush for staining in a special plastic bowl.

Metal bowls must not be used! To prevent the composition from reacting with the dish.
The paint itself is thick, creamy.
Does not flow, does not drip. The amplifier has the same properties!)

Waiting after painting before rinsing from 30 to 40 minutes …

✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ ❃✾ Result after rinsing … ✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁

The hair is a little darker … I believe this is the result of using a mixton!

I read that when using mixtons, the color goes into darkening by at least a tone…

But from experience I can say that after a couple of weeks the color will become lighter!

Ryzhina hammered , but not to the full … But still very good !!!!!!)))

♥♥♥♥ I know that sooner or later there is such a “gold” on my hair will manifest!) ♥♥♥♥

But so far I’m happy with the result …

✾ ✿ ❀ ❁ ❂ ❃✾ ✿ ❀ ❁ ❂ In general, the color has become more matte, cool, muted ….. ✾ ✿ ❀

Mikston matte , hid bright gold!

♥♥♥♥ And in my opinion, he coped well with the task … ♥♥♥♥

✾ ✿ ❀ ❁ ❂ ❃ I would like to be lighter, because paint level eight!))

Shade: 8.1 light ash blond. Blond in its usual sense of course not …

But I haven’t figured out how to become lighter without washes and other procedures unfamiliar to me!)

♥♥♥♥♥♥♥♥♥♥♥♥♥ The girls are cute!) ♥♥♥♥♥♥♥♥♥

If you have any ideas on how to accurately achieve a real eighth tone – share in the comments!) Help me….After all, I know that there are girls here who are real professionals in matters of dyeing … I am still just learning and experimenting …

✾ ✿ ❀ ❁ ❂ ❃ In general, I am happy with the result of coloring with the use of an amplifier!)

♥♥♥♥ Got rid of the bright red color!) I got a natural hair color!)

I hope that the quality of the photo was able to convey the changed shade of the hair, and the effect after dyeing …

And do not judge strictly, this is the first time I use such amplifiers, and maybe my inept experience will help you, girls, with something!)

I dream of healthy long hair!

Hope that someday I will make my dream come true!

If you are interested, you can look into my reviews about other products of the company Kapous.

★★★ Here is a review for Kapous 7.23 paint.

★★★ But the Kapous shampoo, which smells insanely good, but no good … My very first review on this site!)

★★★ Kapous serum is probably the favorite of all long-haired girls on site!

Long hair to everyone!)

Happy New Year !!)))

[FROST] – Against the Wind (Radio Version) Lyrics

Lyrics translated into 0 languages ​​

Thoughts in my head, evening for window,
The wind sweeps our paths
As if he knows that we will not pass anymore
Two of them, and at dawn
Let’s not meet eyes.Didn’t want to be another link
Beat your head against the misted glass
And lie between the window frames _____ ______.

And you will find the answer to your question,

I could keep on fighting
If I could feel the meaning. _____,
But why run after the one who runs
From you with the hope of hiding?
Think about it! When we took one route
But they walked on different sides,
And, even if it sounds so corny, but
Say hello to the cold winds
That turned our hearts into blocks of ice
And so they smashed it so well.
In tattered phrases, there, in the distance
We heard voices that we are different.The greedy crows pecked our backs,
Pecked, celebrating the beginning of the end,
But, while the arrow flew from the sun,
Warming cold hands
We believed that it was not in vain that the heavens united us,
And no one can wait to be separated.

Thoughts in my head, evening outside the window,
The wind sweeps our paths
As if he knows that we will not pass anymore
Two of them, and at dawn
Let’s not meet eyes.
Didn’t want to be another link
Beat your head against the misted glass
And lie between the window frames.

Spread your wings and fly where there is white light
Burns through the darkness, leaving a trail.And you will find the answer to your question
You will begin to shine like a million stars.
Spread your wings and fly where there is white light
Burns through the darkness, leaving a trail.
And you will find the answer to your question
You will begin to shine like a million stars.

Spread your wings and fly where there is white light
Burns through the darkness, leaving a trail.
And you will find the answer to your question
You will begin to shine like a million stars.
Spread your wings and fly where there is white light
Burns through the darkness, leaving a trail.
And you will find the answer to your question
You will begin to shine like a million stars.Spread your wings and fly where there is white light
Burns through the darkness, leaving a trail.
And you will find the answer to your question
You will begin to shine like a million stars.
Spread your wings and fly where there is white light
Burns through the darkness, leaving a trail.
And you will find the answer to your question
You will begin to shine like a million stars.

In tattered phrases, there, in the distance
We heard voices that we are different.
The greedy crows pecked our backs,
Pecked, celebrating the beginning of the end,
But, while the arrow flew from the sun,
Warming cold hands
We believed that it was not in vain that the heavens united us,
And no one can wait to be separated.The greedy crows pecked our backs,
Pecked, celebrating the beginning of the end,
But, while the arrow flew from the sun,
Warming cold hands
And you will find the answer to your question
You will begin to shine like a million stars.