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Hi folks -?

Sharing this repair experience in case it helps others or if anyone has further advice to add.

After a couple of days working fine on 20m and 40m my QDX stopped transmitting and battery current on receive went up from 140mA->320mA. Reading Hans' excellent troubleshooting guide I updated the firmware and suspected at least one blown BS170. Indeed it turned out to have been a bad day for Q11:

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I replaced all four BS170s and, while the board was in front of me, I took the opportunity to resolder some of the inductor windings where it looked like dry-ish joints due to poorly burned off enamel might cause a problem.

The TX side seems OK: on the three bands I have enabled the transmitter is delivering around 2.5W on each of 40m and 30m and 4.2W on 20m. However I seem to have upset the RX side as this is what I get from RF sweeps on all bands:

Given that the TX side is doing OK, is it safe to assume that the LPF inductors are probably OK and I need to look for anomalies on the board around L12 and the trifilar transformer?