K3: Receiving 4th Harmonic of AM Station

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K3: Receiving 4th Harmonic of AM Station

Rick Stealey

On my K3, without a general coverage option, I tuned down below 160 meters and heard some broadcast stations, and compared the signal strength to another transceiver I have which has general coverage.  In the range of 1400 KHz the K3 copied fine, but when I tuned down around 1200 KHz I couldn't copy anything on the K3.  Seems reasonable, that the 160 filter rolled off down in that range.  Why then can a broadcast station clear down at 940 KHz get through to overload the front end of the K3?
Come on!  This is the receiver, the best in the world, that can copy weak signals right up next to 60 over 9 contest kilowatts.  I can't believe this K3 receiver generates spurs from broadcast stations clear down at 940 KHz.  Read his post - he said an FT-900 and a K2 don't exhibit the problem.
My bet is there is a bad component in the front end somewhere.  A K3 should not crumble in these circumstances.
I think it's time to get out the 8640B signal generator and see for myself what level it takes to generate 2nd and 4th harmonics like that in a K3.  I'll know within the next 15 minutes.  QRX one.........

Rick  K2XT
     
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