DX-40/VF-1 chirp continued

[Jim Berry]

Hello Heath Fans,

Right off the bat, I want to make mention that in my earlier post that I
said to run the VF-1 off from say 200 volts.  It will work fine, but to
really take advantage of the voltage regulator in the VF-1, it is probably
better to run it from a supply of at least 400 to 600 volts.  You can do a
little wiring changing in the VF-1 for it to operate at a lower voltage, but
a higher voltage supply is probably actually easier to create.

The separate power supply:  Got an old junker tube TV set chassis laying
around?  It probably has everything you need to cobble up a separate power
supply.  That is what I did.  Hung the parts all together with alligator
clips.  Watch out.  This stuff can bite.  Be careful of any exposed high
voltages.

Also thanks to Al and others for suggestions and corrections to my original
ranting.  Gee, messing with this old stuff is a lot of fun.

Oh here is one:  While playing around with the VF-1 and DX-40 into a dummy
load with a receiver near by at hand with no antenna on it, I noticed that
the signal had become kind of raspy sounding.  Maybe it was that way all the
time, I really don't know.  Heath used a 45 or 47K resistor across the VF-1
output to create a load.  I grabbed my resistor substitution box and clipped
the leads across the existing resistor.  As long as the subbed in resistors
were between 50 and 5000 ohms the rasp went away.  I grabbed a 1000 ohm
resistor and soldered it across the 47K.  Not sure what the rasp was since I
don't have a scope.  It might have been a bit of FMing or who knows what.
Again, everything was in a pile all open on the bench.  Got plenty of drive
from the VFO, so my tacking in the 1000 ohm resistor apparently didn't upset
anything.

Last night I got everything all put back together in their respective
cabinets.  Looking at this pile of dangerous open power supply.  Have to
come up with something to build it in.  Maybe tonight or sometime this
weekend, I can get on the air with it.

73 Jim K7SLI

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