Denis,
Do you have the KDSP2 installed in your K2? If so, check the DSP NR.
If it is on, it can cause distortion. It does an effective job of
reducing noise, but does introduce some distortion - and may appear
intermittent depending on the signals and their level.
If no KDSP2, then check the soldering in the PLL Reference area as well
as the BFO area. Marginal solder connections may have been OK in the
past, but can fail after time. Check the schematic for components in
those areas and re-flow the soldering.
You can also do the Receive Signal Tracing as indicated in the manual.
You may have to connect a strong signal generator as described in the
Troubleshooting section of the manual. An XG1 or XG2 will not provide a
strong enough signal (the XG3 will), so construct the oscillator shown
in the troubleshooting section of the manual.
The power output problem may or may not be related. The best way to
find the offending stage is to do Transmit Signal Tracing as described
in the Troubleshooting manual appendix. When you get to a stage which
produces less than the expected values, that is the output of the
failing stage, and you can investigate that particular stage for the
problem. Re-flowing the soldering may correct it.
Component failure is not the most common cause of failure (soldering
is), so do not jump to conclusions about a component being bad -
exception is if one of the PA transistors has been damaged. If you find
everything up to the PA transistor bases OK, then replacement of the PA
transistors with the K2PAKIT from Elecraft may be in order.
73,
Don W3FPR
On 4/26/2017 5:19 PM, Denis Jackson wrote:
My K2 hasn't been used for a few years but, with the intention of taking it
out for a bit of SOTA work, I powered it up today. Alas, I have a problem.
The receive audio is intermittently distorted on all modes. With a constant
carrier, it sounds like there is a warble to the note. There is another
problem in that it has is that the RF power output is only about 6 watts
(it's the 15W version) and that seems constant on all bands. I don't think
these two problems are related because the power is always low regardless of
whether the audio is distorted or not but thought it worth mentioning
nonetheless
______________________________________________________________
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
Message delivered to arch...@mail-archive.com