Re: Dummy Load experience?

My dummy load is 100% enclosed in oil AND a 1 gallon can. This is pretty tight. I estimate leakage at around -120 to - 130 dB.

I run about 10 to 11 feet of coax from my transmitter to the low pass filter to the tuner to the antenna switch to the dummy load. The coax is good quality 9913. BUT, it uses a woven copper braid as the overbraid. The braid has a leakage impedance of typically 0.020 + jw10^-8 ohms. The inductive term means that the little holes in the braid 'LEAK' rf. At VHF the coax isolation could be -60 to -80 dB. So, a 100 watt signal could leak between 10 and 100 microwatts. If you have a cell phone that power level is close to your cell phone's power output. Your receiver will detect a signal 1 one millioneth as strong.


CD wrote: 
Hi all,

I'm curious about dummy loads. I read that ideally dummy loads convert
RF energy into heat, but I'm sure in the real world, there will still
be a small amount RF energy transmitted.

My friend tried using a dummy load on a 300W transmitter. He was only
running it for a few mins at the VHF range, but he was picking up a
signal 100 ft away. Is that typical?

What's your experience on dummy loads? Were you able to pick up a
signal, as well, with this type of distance?

I don't know much about dummy loads, but I think that 100ft is just a
tad bit too far, no?


.

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