Why no heated gear?

Just so, the external heating of electronic equipment is not really effective.

I have a feeling I'm going to regret asking, but what do you base that on? Experience, some research you've read about, or just a guess? So you are saying an electronic component will behave differently if heated to the same temp if done externally rather than by dropping some voltage?

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Your analogy doesn't hold water. Pouring hot water on your car is a terrible analogy.. A better one would be if you store your car in a heated garage so it is heated all the way through, not just on the surface. In that case it would definitely make a difference, just like raising the internal temperature of an electronic component no matter how it is done will make a difference.

This is done all of the time in precision test equipment. Temperature sensitive components that would affect the precision of the instrument if their temperature was allowed to drift, for instance the components that determine the frequency of a precision oscillator, are kept in little "ovens" inside the device where their temperature is precisely controlled. They are typically heated since it is usually easier to keep something warmer than the ambient temperature than it is to keep it cooler.

Since all Elizabeth can do is claim "you missed my point" and can't offer any reasonable explanation of why heating something up externally or internally will make a difference, I'll consider the case closed.

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The original question was

why don't manufacturers add heating elements to equipment to bring it too optimal temperature quicker.

It is ridiculous to think that externally heating a component won't do just that... "bring it to optimal temperature quicker." It matters not whether you think it is extravagant, that was not the original question.

As to the poster who pointed out that his garage won't heat an engine to operating temp.. same answer. Of course it won't, but an engine starting when it is room temp will certainly start easier and be ready drive more quickly than one that is freezing cold. Keeping it in a warm garage will "bring it to optimal temperature quicker."

As to the theory that tubes can't be warmed because they are in a vacuum, well, I'm sorry but that whole post simply makes no sense. If that were true then they would remain cool to the touch when operating. If heat can't get in then it can't get out. The simple truth is that everything inside is physically connected to everything outside through the base. The entire tube, inside and out, will eventually reach the same temp whether heated from within or from outside. Even if there wasn't a physical connection there is radiant heat which does travel through a vacuum as proven by the fact that we are warmed by the sun. Also, bias has nothing to do with "heat potential" between electrodes, in fact, there is no such thing as "heat potential" in a tube. Bias is used to establish the proper operating point for the tube. Too little bias and you increase distortion, too much can also lead to distortion and can overheat the tube.

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Do you possibly believe that you can pre-heat a tube to anywhere remotely close to operating temperature?

uh, did I ever say that?

And regarding your last statement that there is no such thing as heat potential in a tube. Really?

Despite referencing several textbooks as well as the web I find no mention of the phrase "heat potential" when it comes to vacuum tubes.. I make no apologies if I misinterpreted what you meant when you used unconventional terminology.

So you believe that the anode and cathode in a typical vacuum tube are EXACTLY the same temperature?

uh, did I ever say that?

Granted, the cathode is generally heated to increase electron emission. That in no way negates the fact that keeping the tube warm when it is not in use will decrease warm up time.

You all can ignore what the original poster asked and try to nit pick responses, but the fact remains... if it starts out at a warmer temperature it will reach it's operating temperature more quickly. That is crux of the debate, double speak and patting yourself on the back for clever responses "I just knew that you were going to reply the way that you did" doesn't preclude the fact that any of you who dismissed the reality that preheating the equipment has a positive effect were wrong.

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So i am sort of confused about some saying yeaah, external heat caould do it..

I see why you are confused... because nobody ever said that. Nobody ever said that external heat could keep a component at its optimum operating point.

The question was, would keeping the equipment warm speed up the process of being fully warmed up.. If you look at an extreme example it might help to understand the concept.

Take two identical amplifiers. Store one in a deep freeze and the other under an electric blanket. Take them both out and turn them on. Which one will reach the optimal operating point more quickly?

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I live in NY and I have to say that my tubed gear takes the same amount of time to warm up in the summer as the winter.

I assume you have some sort of HVAC system in your home that keeps the temperature in your home in a relatively narrow range winter and summer; i.e. you heat your home in the winter and cool it in the summer? If so then it should take about the same amount of time summer and winter.

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