Another problem that should be noted is the mode switch on the base station radios. This component tends to be the bottleneck.
On most base stations, the power the the finals gets routed through the mode switch. Because of this, when modifying a base to run a MOSFET, you can damage the mode switch and cause failure due to excessive current draw from the MOSFET in SSB. I had this issue happen on a Cobra 142GTL. Installed the MOSFET, set the bias voltage at the gate, made sure everything was proper, and the radio was doing in excess of 30W PEP on SSB.
Then, *poof*.
No output.
But only in LSB. I put two and two together and realized, that during testing, I had been using LSB to perform my tests, and had damaged the mode selector switch to the point that the contacts on the LSB portion of the switch had burned open, and the switch was no longer usable.
I replaced the mode switch with a beefier switch, and all was well again. But it should be noted that the stock switch CAN potentially fail if you install a MOSFET, unless you adjust the ALC back so the radio puts out lower power.
Also, Kop is 100% correct, it's probably not recommended to run a fixed value resistor unless the proper value is determined first. Even so, it's best to leave a trimmer potentiometer in its place in the event the MOSFET fails.
~Cheers~
