[AMRadio] Monitoring Modulation Accurately


rbethman rbethman at comcast.net
Sun Nov 17 16:33:06 EST 2013


We are just going to have to agree to disagree.

The sample jack on the TR switch fed directly into the TEK 5440 
definitely showed a good bit of flattopping.  Hence the whole deal in 
reducing the Mic Gain.

The plate voltage was in excess of 2300VDC.  I loaded to minimum plate 
current or the "dip" that one tunes an Amp or any PA to.

The R-390A was definitely in 16KC position.  I wouldn't receive AM any 
narrower than that, as it sounds crappy.

The folks giving critical audio reports both when I was flattopping and 
after I reduced the audio would include WC3K, WN3B, W3MTG.  I know that 
none of them would report other than what they heard.  If you've talked 
with them, then you know their straight forward critiques on a signal.

These folks will definitely tell you when you have crappy audio. 
Although WC3K is now an SK.

He was getting his BC-610 up and going after I got mine up.  He wasn't 
all that thrilled with the M.O. tuning of the Tuning Units, and was 
trying to use a Johnson VF-122.

I've gone to using an HP-3336b Frequency Synthesizer for the very same 
reason.  Trying to use the M.O. tuning is frustrating and a royal PIA!  
It is the one place that a Jackson reduction drive would have made GREAT 
improvement!

Bob - N0DGN


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