[Elecraft] [K3] KRX3 installed and ERR VCO / ERR PL1

[John Shadle]

Even though it's quite embarrassing, I wanted to let folks know about
the resolution of this issue. It's also great to have my problem and
solution live in perpetuity on the list in case someone else has this
issue arise when they are adding their KRX3.

To recap, the issue I had was that neither my main nor my aux KSYN3
would complete the calibration procedure if there was a KSYN3
installed in the aux slot. If there was just a KSYN3 installed in the
main slot, everything was hunky dory.

I tried adding DeoxIT to the slots where the main and aux KSYN3 are
installed. That made it easier to remove/replace the units, but didn't
help the main problem at all. I checked the voltage at J1 and J2 of
the KREF3 board, and they were both within range (a little over .9V).
I double-checked to make sure that all the TMP cables were in place,
and that all the plug-in modules were aligned correctly.

*Finally*, I checked the bottom of the board one last time, especially
the work I had recently completed (a couple of upgrades and adding a
resistor to change the value at R91). My error was in the resistor
didn't have a good soldering joint at the point where the leaded
add-on 27 ohm resistor was added and where the 100 ohm SMT resistor
was previously. I reflowed solder there, and then voila, the rig will
complete the calibration procedure for both KSYN3 modules! When I was
checking the resistance before, I think I was inadvertently pushing
the leaded resistor against the SMT resistor, thus making a connection
(albeit temporary) and showing the expected value of 27 ohms. D'oh!

Thanks again to Gary and everyone on the list for their assistance.
I'm looking forward to playing around a bit with the newly upgraded K3
this weekend.

73
-john W4PAH
Madison, WI

On Wed, Sep 5, 2012 at 11:35 PM, John Shadle <shadle at katzenfisch.com> wrote:
> Hi,
> I completed the installation of my KRX3 this evening (and upgraded the
> DSP board on my main RX, too).
>
> When I first turned the unit on, I received ERR PL1. This cleared out,
> then I tried to calibrate the synthesizers. First, I tried the SUB. It
> went through its procedure and then returned E 00005 ERR VCO. I did
> the same thing with the main synthesizer, and received the same
> result.
>
> I did have to add the 27 ohm resistor (tested the resistance
> afterwards, and it was as expected--around 27 ohms instead of 100
> ohms). I also added the jumper wire for automatic front-end
> protection.
>
> I do have an older K3 (S/N 110), so perhaps that's to blame...?
>
> Any help would be greatly appreciated!
>
> -john W4PAH
> Madison, WI