About,
"Hi All,
I have a large dry dummy load and need to add some circuit to measure DC
voltage for radio work.
My question, does anyone have a simple circuit to add to the dummy load
to
produce a measurable voltage? Can I use the simple circuit that is in
the
old Heath kit dummy loads? It is just a capacitor, diode, resistor, and
capacitors.
Any advice?
I use a BNC "T" with stiff wires soldered to the pins on one side. This
allows me to clip on a 100 to one oscilloscope probe, allowing me to
measure V across 50-ohms.
cheers, Jeff"
A 6AL5 with its plates in connected in parallel and its heater connected
to its cathode (to increase voltage rating) works very well. The plates
connect to the coax's center conductor. An RF bypass cap at the cathode
can be paralleled with say, 2 mF for "holding your VM" during SSB peaks.
DC output voltage is picked up at the fil xfmr's center tap.
73, Roy K6XK
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