[Elecraft] Arrgh! I put 12volts into K3 antenna connector!

[n4kd]

Hi Kevin,
The same thing happened to me when a bias-t failed. The damage was limited to the SWR circuitry. If I recall, T4 was replaced and a burnt trace on the pcb was repaired.

- 73,
Dave N4KD

> On Mar 26, 2021, at 00:48, Kevin McGrath via Elecraft <elecraft at mailman.qth.net> wrote:
> 
> I accidentally hooked up a bias tee (DC power injector) backwards, which  put +12V into the K3's antenna connector. The results were not good: a burning smell from the rear of radio. The radio was in QRP mode (<10watts, so PA bypassed?) on 40m when it happened.
> 
> RX appears to be fine. The radio still makes 100W out, but the SWR reads 99.9 on all bands (into a dummy load).  Also, the power control has no effect - power out is always 100W. 
> 
> Looking at the schematic, T4 in the SWR bridge certainly would have been fried by applying 12V to the antenna connector.
> 
> What else did I damage? 
> 
> KevinK6TOP
> 
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