Shocking!


I had built a tube transmitter, and was working on the pi-matching section between the plate output and the antenna. The variable capacitor on the plate had about 400 volts DC on it, with the RF signal superimposed on the top of that.

I didn't even think of which side to connect up to the variable section. I figured I'd ground the case, and the stationary side of the capacitor, and hook the plate up to the rotor side. So now I have +400vdc /w RF connected to the metal tuning knob of the first capacitor. I then hooked up the next variable capacitor between the inductor of the pi filter and the antenna, but on this one I grounded the rotary part, and hooked the stationary part up to the antenna and inductor. So now I have ground connected to the metal tuning knob of the second capacitor.

Everything looked okay, so I powered up the transmitter, and started tuning the pi network. I first grabbed the first capacitor knob, tuned it until I got a dip in the swr meter, then without letting go I grabbed the second capacitor knob, and had 400vdc across my chest through my arms.

I knew I was going to die if I didn't do something soon, so I tried to jump up, backpedal and let go at the same time. Jumping up and backpedalling worked, however letting go was not working. In a very short time I had run backwards knocking the transmitter off the table, and backed far enough away to pull the cord out of the wall. Now all I had to do was wait for the 400vdc to discharge through me. It did not take very long, and I sat there for a long time thinking about life in general.

Shocking!


More Shocking Stories...