Thread: what's too hot?
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Old June 17th 07, 05:55 PM posted to rec.radio.shortwave
[email protected] judithdagostino@msn.com is offline
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First recorded activity by RadioBanter: Feb 2007
Posts: 28
Default what's too hot?

On Jun 16, 8:06 pm, "Ron Baker, Pluralitas!" wrote:
"N9NEO" wrote in message

oups.com...





When talking about radio regulators running too hot what does that
mean actually?


Does it mean that your air conditioned radio shack is too hot because
the air conditioner can't keep up with your so and so receiver?


Does it mean that your desk has a hole burned in it where your rig
used to sit?


Does it mean that you can roast marshmellows with it?


Does it mean that when you spit on it it sizzles?


Does it mean that the thing has a long history of failures because the
regulators burn up?


Does it mean some idiot thought the things were running too hot so
came up with some cleverly stupid modification that doesn't really do
anything of value beacuse more than likely the regulator has thermal
protection and folds back the current when it gets too hot?


What in the heck does it mean?


Are there any electrical engineers here that could tell me in a
quantifiable manner what exactly too hot really means?


NEO


The common "commercial" acceptable temperature range
for components is 0 to 70 C.

Heat typically shortens the life of components.
Chemical reaction (thus aging) rates typically double for every
10 C increase in temperature.

And if it burns you when you touch it that is not
good either. A general design rule is 60 C. There is
a rule of thumb. If you can leave your thumb on
it then it is 60 C or less.

I would try to keep electrolytics cooler. The electrolyte
is less stable than most of the other materials in electronics.

And in general I'd rather have things below
45 C.- Hide quoted text -

- Show quoted text -


Too hot means if you **** on it and it sizzles, it's too hot!

FC