This radio is dual band Heath Kit hand held, Same as the
Standard C528/A
It appears that the VHF Tx has low audio compared to the
UHF., Using my SM, I noticed that I need to turn up the
audio drive that goes to the VCO much more than the UHF
VCO.
Both VCO are of the same design, just using different
size components due to freq differences.
There is a Variac DIODE there being injected via the
Mic audio for the FM deviation.
Both Audio sources for UHF and VHF come from the same
Mic pre amp source using a trimmer from the output for
each band..
The UHF needs only about 50% set point to get the max
5K spread how ever, I need to turn the VHF up to 100% to
make it satisfactory.. This unit has been repair three
times by some one else that has replaced all of the smt
electrolytic caps due to being leaky and thus claiming to
cause the low audio problems. Now I am looking at it.

I guess my question here is this:
Have any of you ever seen a Variac Diode lose/reduce it's
capacitance dynamic range?

--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
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