Re: High SWR on all HF Bands


Spot on on the forward and reverse power signals. Get you a known good piece of coax and use the dummy load to make sure that the coax is good. I check them with the antenna allayer I have as well.
After you have made certain that your coax and dummy loar are good and 50 ohms (use a good ohmmeter too) they you can check not the swr, which is a derived signal in the CPU, but the forward and reverse power readings. With a 1:1 swr the numbers should tell the tale. Forward power should be some value (I forger wha) and reverse should be close to zero (0).
These signals go to the ALC circuit to control power output and drive to the finals. I have had problems in the ALC circuit as well as in the JHREF and JH FOR. The JHFOR is used to regulate the power output and when compared to the JHREF reduce the power to protect the finals as well. 
Somewhere here I have posted the relevant sections of the schematic for the ALC circuit.

Join to automatically receive all group messages.