"A" wrote in message
x.com...

We had a thread recently on Astron power supplies and I thought I'd
mention that I have an RS-35A (35 amps intermittent) for VHF brick
amplifiers (main use) and I've had it for some 20 years. Recently, the PS
has started to "crowbar" off on me (voltage goes to zero) and not even
with high currents (maybe around 15 amps or so) and have to shut it off,
wait a few seconds, and turn it back on.

I also had another different regulated fairly high current DC PS go bad
long ago, in a similar way.

I'm wondering how many others of you have seen defective operation, sooner
or later, or other deterioration in your high current regulated DC
supplies?

And, if the overvoltage crowbar craps out, it blows up your rig? I'm
thinking of going exclusively back to deep cycle marine batteries, again.


Sometimes adding a .1 or .22 uF cap on the gate of the SCR to ground
will stop nuisance crowbars. Some Astrons are more sensitive than others
in this regard. We had a similar problem with a few 50 amp Astrons in
repeater service.

Pete