[Elecraft] Info 080 message started with RF Alignment and Test, Part II

[Don Wilhelm]

You apparently have the new VFO encoder with the PC board that has a few 
components on it.  Not only the encoder board, but the Control Board 
leads in the area indicated must be flush cut (flush with the board).  
Your tape will provide a temporary fix, but I suggest you do a good job 
of flush cutting the leads (including ICs because the cut leads may 
eventually punch through the tape and cause problems later).

As for the Info 080 messages, refer to my prior responses especially the 
connectors and RF board R64 and Control Board R6.

The zero voltage at the left end of R30 is due to a problem in the VFO 
Range Select area (see the schematic for the relays and capacitors 
involved).

It seems that you are having soldering problems in general.  Turn your 
soldering temperature up to 750 degF and look critically at each solder 
connection.  The solder should flow out to an almost invisible edge on 
both the solder pad and the component lead and result in a concave 
solder fillet.  If your solder connections are convex (or look more like 
'balls'), then the connection did not receive enough heat.  Several 
builders have this problem because they remember the old days when 
soldering irons did not have temperature control and the result was 
lifted solder pads and heat damaged components.  That is not the case 
today with temperature controlled irons and components rated for up to 
10 seconds of soldering temperatures.  I suggest you re-flow the 
soldering on all the K2 boards that you have assembled - watch the 
solder as it flows, and if it does not fill the solder pad, add a small 
bit of solder.  In some cases, you may have to use solder wick to remove 
excess solder and then solder that connection anew.  Use a soldering 
temperature of 750 degF or higher.

After the re-soldering exercise, go through the alignment procedures again.

73,
Don W3FPR


On 10/27/2012 2:06 AM, AC8HU wrote:
> Well I thought I was going to be coming on to post what I'd found with the
> VFO problem...but now, the Info 080 is back.  As far as the VFO, I
> discovered that if I removed the two screws that connect the control board
> and front panel board (so that they're not drawn snug to each other), the
> VFO works.  It almost seems like the back of the optical encoder board is
> somehow shorting to the control board?  I don't know...I put a couple pieces
> of electrical tape on the back of the encoder board and gently connected the
> two together with the screws and the VFO was still working.
>
> At that point, I went back to the Part 1 tests and alignment, and started
> working through Part 1 and Part 2 again.  Everything was once again fine up
> until the exact same point - when I switched bands to the 80 meter band,
> before tuning to 4000.10, the Info 080 message popped up again.  I said
> several things I won't say here, then proceded to do the frequency counter
> check anyways just to see where I am.  I didn't actually make a note of the
> value but the frequency was somewhere around 10800, a range of 8 to 10 MHz
> is specified so this would be marginally acceptable (?) I guess.  Just out
> of curiousity, I went ahead and checked the voltage on the left end of R30
> (as described in the next step) and found it to be almost exactly 0.00 V -
> and adjusting the slug inductor made no difference.  Prior to the
> reappearance of the Info 080 message (but before the VFO working again), I
> had checked this value, and again didn't write down what the exact numbers
> were, but I had some sort of reading and was able to make adjustment over a
> wide range using the slug inductor.
>
> Finally, I tried restarting the radio (figuring I knew what would happen),
> and the Info 080 message appeared immediately at startup, and I noticed that
> relay activity is one again nonexistant.
>
> Now I'm rather discouraged.  I didn't check further but I wouldn't be
> surprised if I'm once again seeing the same problems with voltages on U1 and
> such.  Knowing the little bit I know about computer troubleshooting, it
> seems that I can narrow the problem down to something that's resulting from
> the switch from 40 meters to 80 meters while doing frequency counter
> checks...but I have no clue at all what that problem could be.  My best
> guess, since relay activity comes and goes with the Info 080 message, and
> these problems start when I change bands during these tests, is still some
> sort of problem with U1, as I've been over solder connections several times.
>
>
>
> --
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