K2 SN 06114 is complete as of today. OK... I should say that main kit is complete.

I already have the SSB and ATU kits sitting on my bench. Depending on work and family timing I hope to start the SSB kit this week.

I have lost track of how many days I have spent 30-60 minutes here or there trying to track down a low power/Hi Current issue.

It turns out that I had two issues:

1. Low power... about 4-6w instead of 14-15w. After looking at and touch every component in the PA Bias and PA circuits it looks like there was something wrong with T4. I am not sure what... but the problem has been resolved.

2. High Current... looks like L16 and/or L17 in the Low Pass Filter was the problem. I removed them and rewound them.

I spent about 6 hours working on the radio today. (About 4 hours of testing... about 2 hours of construction/repairs.)

I am happy to have a working radio. I hope to be able to spend a little time tomorrow tweaking up the 10m/12m power levels and then button up the radio.

I am ready to move on to the ATU and SSB module kits next.  :-)

I am trying to track down why my power output is low. I have a couple of hours into this today... my vacation day (use it or lose it)

----Snip from the email that I sent to the Elecraft Reflector----
K2 gurus:

I got a note from Gary (support) and Don (w3fpr) with some ideas.

--I checked the low pass filters and the number of turns.
--I validated that T4 is oriented the right direction --No burnt relays
--8R/8T are ~8vdc (R-7.87/T-7.815)
--8R on transmit goes to 0.245vdc
--I clipped W1 to test for PA feedback (no change)
--I removed the bottom panels and cleaned up a couple of joints as a CYA
--Removed and rewound LP for 80m
--Checked & resolder the connections of toroids for 20/30, 15/17, & 40
--Repeaked (on receive) all of the band pass filters with a signal generator
--Repeaked (on transmit) all of the band pass filters

I made some progress: (Original Test... and after some rework)
--Freq-----1 Test----1 Msg----2 Test----2 Msg
 3.750mhz  2.5w      Hi Cur   2.3w      Hi Cur
 7.100mhz  6.1w      Hi Cur   6.6w      Hi Cur
10.100mhz  0.3w      Hi Cur   4.9w      Hi Cur
14.100mhz  0.3w      Hi Cur   5.7w
18.100mhz  9.5w               7.3w
21.100mhz  4.1w               5.0w
24.900mhz  0.5w               4.9w
28.200mhz  6.0w               6.3w

As you can see I am now getting ~5w on all bands except for 80m. I suspect that the toroid cleanup might have been part of the answer for 20/30 and tweaking the band pass brought 10/12 into better alignment.

On the three bands that I get a high current message it appears at the peak power out and does go away if the power is reduced. Any chance that I am only seeing power out of Q7 or Q8 instead of both of them?

Thursday was day 21. I spent the afternoon trying to trouble shoot an RF issue. I built the RF probe and poked around the radio while I was on the phone with Scott @ Elecraft HQ. It is hard to poke around some of the RF amp sections because the bottom cover/heat-sink is in the way.

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Saturday was day 22. I went over to N0FP's QTH. He has an O-Scope. Between two of us we went thru the schematic and compared notes with the O-scope readings. We were seeing RF thru the entire chain where we were expecting it.... just not enough RF.

Using the scope we able to measure the DC and the RF. His scope was fast enough that we were able to see a lot of detail in the RF. Even though T3 tested out properly it looked like the likely problem. I rewound it and put it back into the circuit. I also borrowed some small heat-sinks that would fit on the PA transistors so that we could test the radio without the rear cover.

I am now seeing the proper amount of RF coming out of the rig. I need to take one more pass thru tuning up the Band Pass Filters. Once that is done I need to test the output of each band to make sure that all looks good.

At this point it looks like the circuits are playing as expected. Next phase is to hook up the speaker and close up the case then the basic build is complete.

I have the SSB and ATU option kits to put together next.

Our weather has become cool and rainy, snowy, and ice covered rather early this fall. It appears that I am already visiting in the inside work bench a little more and a little earlier than usual. (Not that inside projects are bad.)

I took today as a PTO day at work (burning up time before the end of the year.) I decided to spend the majority of the day working my Elecraft K2 project. Looking at my blog it appears that last time that I worked on the kit was June 20 which is about 5 months ago... wow that is a long time.

I spent about 6 hours today working on the project. Today's focus was installing the last batch of capacitors, resistors, and then winding cores and transformers. Tonight at 8:30 I got the PA transistors installed and the case put back on the radio. The next big step is the Phase 3 alignment.

This next chunk of testing and alignment will validate that I installed all of the proper pieces in the proper spots. So far I have had minor issues with each phase largely due to dumb things on my part. Each of them was resolved with some troubleshooting, emails, and the occasional phone call to the support folks.

I am not sure if I will get back to the project this week as the calendar is looking pretty full. Worst case... I have another day of PTO planned for next week.    I would like to get the basic QRP CW rig finished and checked out. I still have the Tuner and SSB option kits to install to finish out the basic rig.

My goal is to be able to finish the radio with the above options and then be able to order, build, and validate the transverter option kit prior to the January VHF contest. (Ok... my first goal was to have the radio ready for the 2008 Field Day weekend... I kind of missed that goal... life got in the way again.)