[Boatanchors] Globe (WRL) V-10 VFO - Problem with voltage regulation

[D C _Mac_ Macdonald]

Try the regulator to give you 105V regulated with the specified dropping resistor.  I'd bet the VFO would run just fine with the lowered B+ voltage.  IIRC that's the 0B2.

73 - Mac, K2GKK in OKC


Sent from my iPhone

On Nov 8, 2013, at 15:51, "Jerry" <jsternmd at att.net> wrote

I found a V-10 in great shape but someone had cut the line cord close to the
chassis which made me worry that there were some potentially serious issues
with the VFO.  The inside looks new, however before applying power, I
checked to make sure the power transformer was not shorted.  The xfrmr works
fine supplying filament 6.2vac and separate 175vac to a half wave selenium
(65ma) that I replaced with 1n5408 plus a 200ohm dropping resistor.  I also
replaced the two 30uF lytics and left the large (~10mH) choke between the
two filter caps as it was not shorted either.  Thes B+ supplies the plates
to 6BH8 and 6CB6 using a 0A2 voltage regulator.  I cannot get the 0A2 to
strike at 175vdc from the filtered supply.  I replaced the 0A2 twice with
known tubes and still not striking.   The dropping resistor between the B+
and 0A2 is 47K, 1W per the schematic but in the VFO I found a 560 ohm 1 watt
instead.  I cannot tell if this was done by the previous owners to get the
0A2 to strike earlier or if this was a factory mod not documented on my
schematic.   Can anyone offer advice?

73 Jerry
K1JOS
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