Mike:
Well, you describe the situation with the supply exactly as I experience it.
If I shut the supply off at the switch, wait for a ffew seconds, and turn it
back on, life is good again.
So, we are making progress here.
Will start with the supply and rigrunner connections and some chokes, and
take things from there.
I really appreciate everyone's patience with this thread, but hopefully,
someone in addition to me will learn something too.
73 from Tom Behler: KB8TYJ
----- Original Message -----
From: "Mike Duke, K5XU" <[log in to unmask]>
To: "Tom Behler" <[log in to unmask]>
Sent: Tuesday, February 08, 2011 10:42 PM
Subject: The Astron Supplies
They have what some people call either a crow bar circuit, or a fold
back circuit at the output which will cause the output to become an
open circuit if a shorted output is detected.
The transformer does not shut down, just the electronics around the
output.
Thus, you would still hear the transformer hum.
The reset for this circuit is to turn the supply off at the switch,
and then turn it back on after a few seconds.
Unless the short circuit is still present across the output, the crow
bar circuit then releases, and everybody is happy once again.
It is possible, although I would say unusual, that the RF is causing
the crow bar circuit to think it is dealing with a shorting condition,
so it then does its job and shuts down the output.
Any one of the suggestions that have been mentioned may knock the RF
down enough to keep that condition from occurring.
But, my guess is it will take several grounding and cable re-routings
to really fix things.
Just pick a place to start, and work from that point.
If you are sure your 480 and 811h are sufficiently grounded, it might
be easiest to begin with rf chokes on the AC line of the power supply,
and on the cable between the supply and the RigRunner.
Mike Duke, K5XU
American Council of Blind Radio Amateurs
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