I have been told that the lithium
batteries
used in these circuits could leak and damage if not replaced after so many
years. Is this a real threat?


Ben-

While I can't say it would never happen, I have never experienced leakage from
such a lithium battery. Common practice seems to be to leave it until it dies,
unless you happen to be servicing an old radio for some other reason.

I recently had an experience troubleshooting a problem with a twenty-year-old
Icom radio. Assuming the battery was the problem, I replaced it.

I found that the original battery still had a charge, and the replacement did
not fix my problem! In fact, I used that old battery to temporarily replace a
dead one in a ten-year-old Kenwood TS-50, while waiting for a new battery to
arrive.

Depending on the battery, nominal voltage may be around 3.2 to 3.6 volts. If
you measure the old one with a high impedance meter, and it reads 3 volts or
greater, then you still have some life left in it. If it measures below 3
volts, it may still function, but time is running out.

73, Fred, K4DII