99.5% of the people who built at least one K1 enjoyed doing so and I am no exception. This article summarizes my K1 building experience hoping that other prospective K1 builderswill find it useful.
Doing some last minute QSO with the K1 before I head back to CPH. It was a rather joyful weekend with good test conditions of the K1. When the K1 gets back to the lab I’ll have following points on my TODO list:
Today I made some more QSOs using the K1. Here are a few examples:
At 09:05 UTC I called EA6NB, Jim, on 10.108 MHz. He returned my call with 549, but then he lost me. The band was indeed strange with a lots of QSB.
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!
It’s quite late and I really should have gone to bed but I simply couldn’t resist to turning on the K1.
This page gathers some useful reference material about the Elecraft K1.
- The K1 pages at Elecraft
- Local copy of the K1 docs (versions applicable to my model)
- The K1 data sheet
- The K1 quick reference card
- The K1 assembly manual rev F and corresponding errata sheet
- The KFL1-2 two-band filter board assembly instructions rev H.
- The KFL1-4 four-band filter board assembly instructions rev A and corresponding errata sheet.
- The KAT1 automatic antenna tuner assembly manual rev C and corresponding errata sheet.
- The KNB1 noise blanker assembly manual rev C and corresponding errata sheet.
- Tom N0SS has a lots of usefull stuff for the K1.
- K1 reviews at eHam.
Small BoomBox and mojo to go… This is how NN6CW and many others describe the K1 – a small, lightwiegth QRP transceiver kit from Elecraft. The K1 has been a legend ever since it came out. It is easy to build, looks very professional, has a superb user interface, and offers great perfomance.
I have now waited more than two weeks for the 2SC1969 that I have ordered from El Supply. Since the Easter holidays are coming closer and closer and I want to have the K1 with me, I looked for another source. I found Brinck Elektronik who has a shop in Copenhagen city. I was lucky enough to get the last piece they had on stock. They can still order it for me later but it will cost twice as much.
Yesterday I have done the transmitter signal tracing using my Velleman PCS500 pc-based oscilloscope. Here are the results:
PRE (0.04-0.09) 0.025 V
ATTN (0.02-0.05) 0.047 V
OSC (0.01-0.04) 0.019 V
MIX (0.1-0.2) 0.042 V
BUF (1.5-2.0) 1.74 V
TR1 (0.5-1.0) 0.66 V
BPF (0.5-1.0) 0.78 V
TR2 (0.5-1.0) 0.72 V
TR3 (<0.01) 1.5 mV
DRV (0.9-1.6) 3.7 V
PA (10-15) 0 V
ANT (10-12) 0 V
RFD (1.7-2.0) 0 VDC
That was enough to convince me that it the the PA stage that is doing something wrong. I took the chance and cut Q7 out and it was indeed dead. I couldn’t measure any BE/BC resistance in any direction and the hfe was 0, too.
First I wanted to order replacements from Elecraft but the postage and Danish VAT would have made it 4 times as much as the price of the transistors. Instead I ordered two of them from the Danish El Supply together with some 1.5 and 2.0 amp fuses 😉
Unfortunately, El Supply did not have them on stock so I will have to wait about two weeks. Well, I can concentrate on other projects in the meantime.