I went back to work on the ET-1R, my relay-based version of the single FET transceiver (check the index on the left under Minimalist Radio for more on this). The contest this weekend (was it CQ WW DX?) gave me plenty of signals to tweak the receiver with. I finally got the RX in the right freq range, and I have a nice banset/bandspread arrangement with two variable caps. I attacked the dreaded hand capacity issue via the use of non-conducting attachments to the capacitor shafts (one is the cap from a pen, the other is a piece of wood from a clothes pin).The slaughter of innocent MPF-102s has ended (some victims are visible on top of the SPRAT). The culprit was NOT voltage spikes from the relay coil (although that might have contributed). Instead, what was happening was that I had the gate voltage set way too high on the transmit side. Whenever I powered up the rig, it was for an instant in the transmit mode (before the relay kicked in). The high voltage jolt on the gate was enough to kill the FET.
You can see the transmitter tucked in behind the relay. It moves my SWR meter on key down, so I'm confident I can get at least one QSO (perhaps across Rome) with this rig. Then, I intend to retire it. It will probably be a few years before I forget the pain and decide to build another minimalist regen rig.
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