[R-390] break-in question, 390A and 390

[Tisha Hayes]

Would it be worthwhile to dump the B+ when in break-in mode or is the decay
of the B+ potential too slow to be effective?

I was sort of thinking it as the oft-cursed standby mode on the switch. I
know that it opens up the B+ (causing it do do unpleasant things like really
climb in voltage after solid-stating the rectifiers). Maybe there is too
much capacitance on the B+ for it to decay down fast enough for break-in
operations. You would almost need to open up the B+ supply at the same time
you short out the B+ load so there is not that unpleasant fading effect as
B+ discharges.

It would not do to just open B+ up at the audio stages, you would want the
AGC to not see this tremendous signal as if it is set to slow you will get
the moment of silence as the gain is decreased in the RF stages. On the
other hand you do not want to cut out the B+ to things like the oscillators
and PTO.

It seems like there would be a few things needed; 1) dump the RF into a
short to prevent really crazy high RF levels from hitting the receiver. 2)
Open up B+ and short the load side to ground (through a resistor). 3) mute
the audio.

-- 
Ms. Tisha Hayes/ AA4HA
-
*"Learning is not virtue but the means to bring us an acquaintance with it.
Integrity without knowledge is weak and useless, and knowledge without
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