[AMRadio] The Solution


David Knepper cra at floodcity.net
Sun Jan 2 11:42:20 EST 2005


Today I found an open 20K/150 watt resistor (one of two screen dropping
resistors) that was open.

Since the 4-400A's did not have screen voltage the high voltage soared which
may have caused the plate current meter to show negative current - too much
voltage floating around inside the meter.

I did install the same meter in the 30K-1 and it reads perfectly, which
proves this theory that the excess voltage is causing some kind of corona
charge inside the meter or something to that effect.

The P.A. amplifier (4-400A's) had no screeen voltage, thus, no R.F. output.
No wonder the R.F. current meter was not showing any R.F. current!

I will install a new 20K screen dropping resistor and see what happens.  I
just bet that this will solve my problem.

Anyone with a dunce cap, please send it to me.

Thanks for all the suggestions that I received.  You guys are super-smart
and were on the right track.

More later  on this matter once I install the new resistor.  Let's hope that
this solves this vexing problem.

Dave, W3ST
Publisher of the Collins Journal
Secretary to the Collins Radio Association
www.collinsra.com
Nets:  3805 Khz, Monday/Wednesdays 8 PM EDST
          14250 Khz Saturday, 12 Noon EDST





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