RadioBanter - View Single Post

March 7th 05, 08:29 PM

wrote:
wrote:
My wife and son are both E.E.'s and their explanation is that IC's
begin to degrade slowly as a result of impurituies in the wafer.
Simple components like capacitors dry out and resistors begin to
open
up. Wish I knew more, but I can hear what they tell me in the
radios
I've owned. I owned one of the comparison radios, the Panasonic
RF5000b. Big beast of a 24 pound radio with four antennas. It was
pretty insensitive by any measure. Sure it would catch the big
nighttime SW's but that was about it. Other radios, such as a
Radio
Shack DX150b were still pretty sensitive (and still raspy sounding)
after 25 years, so the rate of degradation isn't a constant.

Do a net search on "eletro-migration".
Over time the electrons carry some of the ions that make
junctions either P or N. Electro-migration increases with heat,
I think it doubles for every 3C degree increase. This is why
overclocking CPUs cn lead to unexpected failures.
Terry

JS That's good information. And it's not too surprising that IC's
are temperature sensitive since we use heat sinks and fans to dissipate
heat. Could also be why some of the Radio Shack Pro scanners tended to
die early deaths when a faster crystal was added.