[Heath] HW-101 VFO - more yet

[Kenneth G. Gordon]

OK. Several discoveries:

1) BOTH BJT "zeners" in both VFOs are open.

2) Removing the "defective" VFO from the rig, removing the open BJT, and replacing it with 
a junk-box old GE 9.1 V 1 watt Zener (all I had), I measure 8.89 VDC where the manual 
says one should measure 8.7 VDC. 

3) The defective VFO works just fine....as long as I have a DVM test lead connected to the 
JFET's source-lead at C-945... from this I draw the conclusion that the higher voltage from 
the open BJT has caused the JFET to deteriorate to the point it needs more feedback in 
order to work. Possible? Maybe...

I'm going to order a few LM336-5 and LM336-9 precision Zeners from Mouser today, and a 
couple of J310 JFETs.

It is kinda tight in the completed VFO, but I manage.

More later,

Ken W7EKB

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