K3 Stopped Transmitting

[Ed Schuller]

I was using my K3 in the NAQP contest yesterday, and took a break and turned it off. When I came back, and turned everything on, there was no output on transmit on any band or mode. If I reduce power to under 10 W, I get around 2 watts out. Once the power knob is moved above the low power setting, I get zero. I reloaded the firmware, and also reinitialized the config file (using a known good file). Still nothing. My K3 is factory built, and less than 2 week sold (after waiting for over a year for delivery). The receiver,including the sub receiver,works fine. I'm stuck (and more than a little frustrated...). Any ideas??
   
  Thanks...
   
  73,
  Ed - K6CTA
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[Jim Brown-10]

On Sun, 17 Aug 2008 09:36:04 -0700 (PDT), Ed Schuller wrote:

>I was using my K3 in the NAQP contest yesterday

Hi Ed,

My K3 is about two months old. Just before NAQP CW, I left it on
overnight, having verified that everything was working with N1MM and
SO2R (with the MP) the night before. When I came in the shack an
hour before start time Saturday morning, I had no RF out at all, but
the keyer/paddle made sidetone. By the time I had finished
troubleshooting, the keyer had stopped working. It's currently in
line for repair in Aptos. Initial diagnosis is that the 10W power
amp died.

73,

Jim K9YC



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[Guy, K2AV]

I've had the same problem with #1239.  I have made some observations about it.  

1) It does not involve the KPA3.
2) The behavior is as if the power had been set to 0.0 by a program bug. Cannot hear the carrier externally on CW -- when it's working I CAN hear the carrier with power set to 0.1 w on the K2 setting next to it.  When it's working and I set power to 0.0 I do NOT hear the carrier on K2 setting next to it.

When power is at 0.0 I still hear some VERY low level phase noise or keying artifacts. When the trouble is in effect, I still hear the keying artifacts.  

I have several times caused the power to return by simply putting the rig in TUNE and leaving it there. It will come back to power over a long interval (5 minutes?) in a very jerky manner and suddenly kick in at 100 watts from somewhere in the 5-6-7-8 watt range. Idea here was to burn it in or burn it out.  But neither happens, and it happens semi-randomly -- Seems to happen mostly when turning it on after cooling off overnight.

Could this really be an ALC bug?

Is there a diagnostic we can run, or a test procedure to further isolate this trouble?  Would really love to solve this before the contest season.

Guy.

Jim Brown-10 wrote

On Sun, 17 Aug 2008 09:36:04 -0700 (PDT), Ed Schuller wrote:

>I was using my K3 in the NAQP contest yesterday

Hi Ed,

My K3 is about two months old. Just before NAQP CW, I left it on
overnight, having verified that everything was working with N1MM and
SO2R (with the MP) the night before. When I came in the shack an
hour before start time Saturday morning, I had no RF out at all, but
the keyer/paddle made sidetone. By the time I had finished
troubleshooting, the keyer had stopped working. It's currently in
line for repair in Aptos. Initial diagnosis is that the 10W power
amp died.

73,

Jim K9YC



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[Jim Brown-10]

On Mon, 18 Aug 2008 09:42:29 -0700 (PDT), Guy, K2AV wrote:

>Would really love to solve this before the contest season.

If you haven't already done so, you should definitely call Elecraft
support. When describing your problem, tell them that we've talked
about it, and that MAYBE there is something in common between your
problem and mine. In their first stage look at my radio (before
putting it queue for to their best bench guy to fix), they noted
that it was the 10W amp that is not running and that a board
connector was not as well seated as it might have been. This was a
kit, so blame me for that.  

73,

Jim K9YC


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