[Elecraft] K3: past chirp report

[Ron D'Eau Claire]

In a synthesized VFO rig like the K3S, any tendency to "chirp" is almost always related to the synthesizer momentarily losing frequency (or phase) lock. 

While that could conceivably be linked to change in the power bus voltage, it's highly unlikely since the bus is isolated from the actual synthesizer by voltage regulators and filters.

OTOH, the OO's report was strictly advisory. I have experienced spurious OO reports over my >50 years of pounding brass, and one that turned out to be accurate when I blew the filter caps in the transmitter and did not notice, nor did the stations I was working report the hum on my signal. When I got a "chirp" report one time (on a homebrew rig) and was unable to hear it myself, I sent a friendly letter to the OO. He replied that he was "almost sure" he could detect a "slight chirp" so he sent the card. 

So my advice is that if you can't repeat what the OO observed, don't worry about it. 

73, Ron AC7AC



-----Original Message-----
From: Elecraft [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Doug Smith
Sent: Thursday, January 19, 2017 11:09 AM
To: Elecraft Reflector
Subject: Re: [Elecraft] K3: past chirp report

Yup, that was me.

There were some good suggestions made here and I’ve checked them all and I’m unable to get the K3S to chirp.  So, at present: unable to replicate..

Some of the suggested things I’ve checked:

1) SWR at the K3S while driving the ACOM 1500 (same operating conditions) is 1.05 to 1.  SWR between the ACOM and the antenna at the noted frequency is 1.2 to 1.

2) Voltage at the K3S is 13.8 key up and 13.2 key down; seems OK.  Power supply is a switcher which I’ve used for some years.

3) K3S is drawing 21.96 amps key down.  (Not running 100 watts into the amp.)

4) I’ve intentionally “mis-tuned” the amp just in case that is what was going on when the OO noticed the chirp.  I did this by tuning up properly at 14.001 and then QSYing to 14.083 and transmitting while monitoring with a different receiver.  No chirp, clicks or other anomalies.  This is a much worse operating condition than I normally encounter.  It’s so easy to tune the ACOM that I keep it properly tweaked.  Also, I was operating in CW SS and in the middle of a 2 hour run when the OO heard me chirping and I have a tough time imagining that I’d sit on a given frequency for two hours without making sure I was properly tuned.

5) I do not use ALC between the K3S and the ACOM.  I do run with specific power levels on each band (great feature, BTW) such that I’m not able to overdrive the amp.

6) I’ve checked my in-the-shack coax jumper cables and I don’t see any issues.  The antenna end of the coax is currently under 2 feet of snow so I haven’t looked at it.  But, I’m getting normal SWR readings here in the shack.  There isn’t any arcing going on or the amp would shut down.  No RF in the shack; no TVI or other issues in the house.

7) I recently made 535 QSO’s in NAQP CW and did quite a bit of listening on a second receiver, never heard a chirp.  I wasn’t using the ACOM so I ran the K3S at 100 watts.  And, finally, I have not yet received another OO report after the NAQP.    ;-)

I dunno what to think.  The issue remains unresolved but I am unable to replicate the problem.

73,
Doug, W7KF
http://www.w7kf.com <http://www.w7kf.com/>



> On Jan 19, 2017, at 9:44 AM, Richard Fjeld <rpfjeld at outlook.com> wrote:
> 
> A few weeks ago, someone had received a chirp report.  Did that ever 
> get resolved?
> 
> Dick, n0ce
> 
> --
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