[amsat-bb] Electronic components might survive lunar temperatures

["William Leijenaar" <pe1rah@xxxxxxxxxxx>]

Hi AMSATs,

Some time ago there was the big discussion about a moon station. Many 
believe it is expensive or technical impossible.
The first might be a problem but about the technical problems I think they 
can be solved.

Because my interrest is the technical issue, I try to find some solutions to 
the problems. One of them is the extreem high and low temperatures on the 
lunar surface.
In previous messages I read they might reach up to -200C and +200C.
For a lunar station it would be an advantage if it can survive these 
temperature :-)

Today I did some tests with normal components expossing to 200C for a period 
of 2hours (in mothers oven). I tested four BF968 PNP transistors (I got many 
for free from a friend, so nothing to loose :-) an 1206 metal-film SMD 
resistor, two crystals and a 1N4148 diode.

Because I can not take my lab to the kitchen (where is the oven) I do only 
test if the components survive a 200C temperure without operation. The 
results were very good :-) After 2hours of 200C I tested the baked 
components again and I could not find any difference. This means that 
"normal components" might survive a 200C moon period without operation. For 
a moon station it means that it can switch of at to high temperatures and 
switch on again when the temperature is at acceptable level to do operation. 
(some kind of none electronical device like a bi-metal could do the job :-)

Actually I expected the transistors to be internally damaged. Maybe longer 
exposure will damage them as well, but thats for furter tests. Now +200C 
might be possible, the next unknown is -200C :-(
I'm still thinking out how to test this... its to cold for my refridge 
unfortunatly.

Maybe someone has more information about the "surviving of components under 
extreem temperatures" ? (not operation but storage temperatures!!)

The components survived well but a bigger problem was the soldering.
After a while some components became unsoldered, and I know that tin gets 
brittle after many times changing from hot to cold. I'm also looking for 
some way to overcome this problem, but I guess this is a much bigger problem 
than the components.

Somehow there will be a way to overcome all problems, and we will finally 
have our lunar-sat :-)

73 de PE1RAH, William
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