[Elecraft] K1 transceiver kit won't transmit

[Don Wilhelm]

Martin and Micah,

The information Gary gave you is exactly correct.
I would add three additional comments:
1) The oscilloscope should have a 10X probe for reliable readings 
(otherwise use an RF Probe)
2) If you have a 4 band board, start with the trimmer slots parallel 
with the long edge of the board - the final settings will not be more 
than 20 degrees from that position.  You must align 15 meters (or 17 
meters) before 20 meters, and 30 meters before 40 meters (the band order 
is not important for the 2 band board)
3) After peaking the Pre-Mixer bandpass at P1 pin 6, go on to peak the 
TX Buffer output, and then with the probe still on the TX Buffer output, 
go back and touch up the Pre-Mix again - the 'scope probe may load the 
premix filter output a bit and must be tweaked again without the probe 
on P1 pin 6.

Observe the sequence of alignment, it must be done in order.  Let us 
know where the expected RF voltages cannot be reached.

73,
Don W3FPR

On 3/4/2013 1:49 AM, Foreman wrote:
> My son and I have been building a 20m & 15m K1 over the past year. Great kit! It is assembled and we are trying to finish aligning the radio. however, it will not transmit. We have tried signal tracing it and cannot get a reading on any of the test points. Receiver works fine. We did extensive multimeter testing and found that IC U8, SA602AN, was out of tolerance. We replaced it but the transmitter is still inop. A very kind Elmer will assist us with test equipment but wanted to gather opinions from the reflector participants on how to proceed. Just to bring all the information together here in one place, the great folks at Elecraft shared the following recommendations:
>
> Filter Board RF voltages using a scope at these filter board connector pins:
>
> P1-4 Premix oscillator signal 200-500mVpp
> P1-6 Premix signal output signal 200-500mVpp (must be peaked with the bandpass trimmers)
> P2-1 TX Buffer output 1-3Vpp
> P2-8 Filter board TX output to Driver 1-3Vpp
> P3-1 PA output up to 40-55Vpp
> P3-8 Output from lowpass filter 40-55Vpp
>
> Vpp = RF volts peak to peak.
> mVpp = RF millivolts peak to peak.
>
> An RF probe will show the rms RF voltage levels, or about 35% of these pk-pk values. Appendix E, or any ARRL Handbook shows how to build an RF probe. We also sell an RF probe kit for $10. Use an oscilloscope if you can get access to one.
>
> Test the rig on all bands too. The filter board is difficult to align the first time, so be patient when aligning it, and try to peak it on signals in receive, or in transmit with an RF probe or scope at the indicated places shown above.
>
> Thanks.
>
> Martin, KL3ID
> Micah, KL3IE
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