On the Air with the K1

My K1 had a rather turbulent start in its career, I must admit. Somehow I managed to blow the final twice before it actually got on the air. Shame on me!

The first time it was Q7, the final itself. THe second time I only blew D19, the diode protecting Q7. Both cases were while playing around with the ATX-1080. In this respect I must admit that it does indeed make sense to simply get the KAT1 tuner right away! I think that would have protected the final.

Blown D19 wasn’t really a problem, so I simply removed it I tested the K1 on the air without it. Eventually I will have to get a new one. I used my DX-88 and so I knew the SWR was all right on the bands I was going to use.

The first day I ended up making four QSOs; two on 17 and two on 30. The 20 and 40 meter bands were simply impossible because of the IARU region 1 field day. The very first K1 QSO was on 17m with Gus, OZ/DJ8QP, who was at Rømø island, not far from my QTH, hi. Tnx Gus!

The K1 works really good. The receiver is very quiet and there is not much noise in it. The menus are easily accessible and adjustable. I also tried to set the break-in delay from the default 50 msec to 0 but it didn’t make too big differene, and so I have set it back to 30 msec. The message recording and playback is very cool! There is space enough to have a full CQ message in one of them, and the name and QTH stuff in the other.

I did, however, notice a few peculiarities, or lets just call them quirks:

  1. The AGC is way too slow. This is a well known issue, and it has been discussed extensively on the Elecraft mail reflector. The reason for it is that the AGC in the K1 is audio derived and thus it is impossible to make it react fast (low frequency). You would need a 100kHz or so IF to implement FAST AGC.
  2. The first two dots on a new band are not transmitted. Well, the fact that it is two dots is just coincidence, it is rather a time delay. I will have to ask the reflector about this.
  3. Sometimes the frequency display shows a wrong frequency for a while when switching to RX. I only noticed it a few times on 30 meters and it can be due to not too good SWR? The SWR was around 1.5.

On the positive side I can also mention the RIT. It covers +/- 4 kHz so it can even be used to split operation.

Already the second day – June 4, 2006 – I have witnessed the well know K1 Mojo-Miracle! At 18:46 UTC I had a nice QSO with GM4SLV John from the Shetland Island running K1 1672. It was a great feeling. Then at 23:56 UTC I managed to have QSO with W1MK on 20m. K1 with 5W and more than 6000km! Thanks Rob for having very big ears.

My K1 surely got the mojo! No doubt about that.

Finally, I would like to compliment the variable width IF filter. I have never had any receiver that could go below 500 Hz width, thus having the K1 go down to 200 Hz is amazing! In general, the receiver simply rocks!

Author: Alexandru Csete

Embedded software engineer in the satcom industry during the day. Radio amateur and SDR hacker during the night.