Steve, You should be able to balance the wattmeter bridge even if the ADC inputs to U1 are damaged open - if they are damaged in a shorted condition, yes they would interfere with the balance adjustment.
I suggest that you try rotating the pots to the full CCW position and then attempt to balance the bridge while measuring the DC voltage at the hot end of R2 - try to adjust for a minimum reading on your DMM rather than a minimum on the K2 display. If that is not successful, then look at C54, C55, R3, R4 and T1 carefully. But if that null adjustment is possible, you likely do have a problem with U1. We had some nasty thunder-boomers over here in the Wake Forest area yesterday and we disconnected everything - I think Chapel Hill got hit harder - so if you had antennas connected ---! 73, Don W3FPR Steve Jackson wrote: > K2 #771, the world's most experienced Elecraft, popped D1 and D2 on the > KAT2. I fear that it also took out the two ADC inputs on U1. CALn does not > work after replacing the diodes. The reading is very noisy. There is also > not any power control which could mean something else is also fried. Anyone > else ever have this happen and if so what did you do to fix it? > > Steve KZ1X/4 > Sent via Motorola Droid > >From W4EZ field day site > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
