[Johnson] Neutralization of the 807 in the Adventurer

[Richard Peterson]

Parasitics are a story all of their own, but separately, it is easy to tell 
if a final is neturalized -- or, at least, pretty close to it. Here's how: A 
neutralized transmitter will have maximum power output at the "dip" at 
resonance. If max power out is not at the dip, the rig may not be properly 
neutallzed.


From: "Sherrill E. Watkins" <SEWATKINS at dgs.state.va.us>
To: <Johnson at mailman.qth.net>
Subject: [Johnson] Neutralization of the 807 in the Adventurer
Date: Thu, 10 Jun 2004 13:43:46 -0400

Gentlemen: How can one be sure if the 807 is in fact truly neutralized and 
is
not also having parasitic oscillations? Years ago, (circa 1956) I had a
"Griefkit" DX-35 and the 6146 would runaway on 10 meters. This was evidenced
by the fact that the anode would quickly turn red hot when keying. This
transmitter had no neutralization capacitor but did have a parasitic
suppressor in the plate lead. It was acting like it had a parasitic or some
type of oscillation even though it had a suppressor. I also had a National
NCX-5 that "exploded" in the final tank band switch from some type of
oscillation even though it was neutralized and had parasetic suppressors. 
The
final tank band switch was severly burned from high voltage flashover and 
the
arc sounded like someone welding! Before I could get the transmitter turned
off, it had severly burned the switch. The NCX-5 used TV Sweep tubes, 6GJ5
type? That rig was another dog I no longer own. - Thank you for all for the
comments!- Sherrill W. k4own.
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