"Ham op" wrote in message
...
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.

Ahhh! You stole' my thunder. Coax typically only has 60-80 dB isolation at
best and that is if it is made well and connectors are on well. Before it
even gets to the coax connector of the radio, there'll be some radiation.
73, Steve, K9DCI