Hi Bill,
There are a lot of reports of QSOs with the Light-bulb-dummy-load antenna. It happened to me too and sometimes the distances were pretty good - several hundred miles. It's what we had. Our transmitters did not require a 50 ohm load to function well.
Take a look in our radios now. The are output filters and those do not work if the load is very far from 50 ohms. Some of us get away with using 75 ohm coax but that doesn't give us a wild 'SWR' and doesn't necessarily look like 75 ohms to the transmitter. The finals can tolerate it and everybody is happy. SWR's that run far afield can expose your finals to higher voltages and destroy them. The old tube gear is more reliable and cleaner if we tune it into a 50 ohm dummy load and then arrange for it to see a 50 ohm antenna system. There is no reason not to do it that way. By the way, 50 ohms has become a defacto standard. It could easily have been 32 ohms, 75 ohms, 110 ohms or whatever. But everythong critical is now designed ofr 50 ohms so just go with it.
A couple of seconds into a light bulb is not going to hurt most of the time maybe never. The information obtained that way is inadequate for regular operation. So there is not much point in using the light bulb dummy load. It's just an interesting show n tell item and it could risk your output transistors if overdone. "Hold my beer and watch this."
73,
Bill KU8H
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On 06/16/2018 12:41 PM, William Cullison wrote:
Off topic but you brought back memories. As a novice back in 1966, my
DX-40's only dummy load was a 75w bulb. I even got my "Rag Chewers Club"
certificate on said "dummy load."
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bark less - wag more
