Hey Dennis did you ever forget to remove a clip lead and hit the HV button?
I'll plead guilty to that one. The old RCA klystron-based UHF transmitters ran 18-25 KV, depending on the model with supplies that were capable of delivering a dozen or so amps all day, every day. They were huge rigs that you walked inside of to service. As soon as you were inside, the first thing you did was use the shorting stick on all of the capacitors. Next, you hung the stick on the HV bus coming off the rectifier stack. You then used an additional shorting stick to ground out whatever part you were about to work on.
More than once I hit HV on with the stick still in place. It was no big deal. The breakers popped, you reset everything and tried again. Not once did I ever see any real damage done to one of those rigs by forgetting to remove the shorting stick before beam on.
It's also interesting to point out that all of those transmitters was equipped with a special relay gizmo thingy that would short out high volts when the beam was turned off. In all the 30 years off and on that I've worked on UHF television transmitters I never once experienced the big bang with the shorting stick. The occasional arc and spark, but never wound up discharging the full load. I know others who were not so fortunate, but lived to tell about it thanks to their shorting stick. I should also point out that every UHF rig that I've ever seen has some sort of interlock that automatically grounds out the HV whenever any dangerous area is open. In spite of such precautions, a shorting stick was always provided and always used before sticking one's hands inside. Even so, I always felt a little squeamish whenever I first reach inside.
I can assure you that I've never, ever worried about popping a capacitor. As far as I am concerned, using the shorting stick is a part of normal operation. Any component that dies as a result was poorly designed in the first place.
Alan WA2DZL
