[AMRadio] Freezing electrolytics and other stuff

[w5jo at brightok.net]

Charlie,

Check the specifications for the caps you plan to use.  Looking at the 
specifications for aluminum electrolytic caps I see the minimum operating 
temperature range from -25 to -50 C.  I looked at the Mouser site to find 
those numbers.  Give that information I don't think I would be concerned. 
What is of concern is how old they are.  As they age the paste will dry so, 
if you are using caps that are old I would do a leakage test.

A few years back I ordered some Sprague caps to have for stock.  They have 
been stored in a climate controlled atmosphere (read indoors heated and 
cooled) for about 6 years.  I installed some of them in a receiver and in 
about a year they started leaking.  I replaced them with more from stock and 
the same thing, so I ordered new ones and the problem went away.  I can only 
guess they all came from a bad batch.  They were of different values and 
voltages.  I have yet to understand why that happened.

Jim
W5JO

-----Original Message----- 

Charlie,

Put a few Electrolytic caps in your freezer.  after a week or so, take
out and test.

I'm going to do that myself, and then test to see if issues arise.

Regards, Bob


On 1/3/2016 3:39 PM, CL in NC via AMRadio wrote:
> Do to circumstances beyond my control, I am having to relocate my shop to 
> another building.  Prior to this move, my shop was attached to the house 
> and had some residual heat getting in that kept it OK, nothing like the 
> temp swings now.  Right now I use a kerosene heater when I am out there 
> working, but have been leaving a special type of electric heater on when I 
> am not there when freezing temps are expected.  So far, the electric unit 
> keeps the temp around 40 if it's 20 out, but a 8 cents a KWH, it will get 
> pricey fast.   The building is insulated, but ran out of money to put 
> siding on it yet, just insulation board and R13 fiberglass.  On the chance 
> that power fails and it is zero outside, and other than a long time for 
> tube gear oscillators to stabilize after turn on,  what are the effects of 
> freezing temps on things like electrolytics?  I've got a couple pieces of 
> higher end test equipment, a comm service monitor and a Tektronix 465M 
> scope, any adverse effects on those?
>
> Charlie, W4MEC in NC