After a, gulp, 3-year hiatus, KX1 No. 2255 is back on the air!
It’s been a long time, too long, really, but I finally got a ’round tuit and used it to finish a project that adds two ham bands to my basic Elecraft KX1.
This was my first serious kit in decades. How many? Try the late 1970s, when I built Heathkit’s 2036A synthesized 2-meter FM transceiver and an HW-8 QRP radio, much modified since then. I still have both.
My initial KX1 build set the radio up to cover 40 and 20 meters. It worked perfectly right after button-up. One of my first contacts from the back deck and a simple wire antenna was PY7GK in Brazil. The contact was no cake walk. But we got it in the log.
After using the radio for several months, I figured it was time to add the final two bands. Well, that was three years ago, and the mod has been hanging fire ever since.
Why? All I can figure is a mild case of toroidophobia. It’s that malaise that can set it, even when one has successfully wound, tinned, and mounted the coils and transformers needed to get the basic radio operating in the first place.
Finally, with the summer of ’13 fast approaching, I figured it was time to get off my duff. But, I admit, I took the easy way out. I bought a set of prewound toroids from Mychael Morohovich, AA3WF, a.k.a the toroid guy — a meticulous craftsman, I must say.
That purchase greased the skids for completing the modification. After tweaking the winding spacing a bit, I get 3 to 3.3 watts out on 4o and 20 meters. I get 4 watts on 80 and 30. One slight hitch: When I installed my autotuner board, the power output on nearly all bands dropped by a watt or two. I tend to use an outboard tuner anyway because it’s more flexible. But I don’t recall a similar power drop when I initially used the ATU on 40 and 20 meters.
I suspect that a relay on the ATU board impinges a bit on the windings of one of the filter-board toroids, changing the spacing and altering the output. So, for now the ATU is out of the case.
That said, the radio works!
As for toroidophobia, I’m building one of Doug Hendricks’s SOTA tuners. I’m winding those toroids myself using the chopstick approach I came across last year on the web. I’m still getting the hang of it, but it’s nice having that culinary tool as a third hand!
This entry was posted on 2013/07/09 at 18:33 and is filed under Portable operations, Projects, QRP with tags amateur radio, Ham radio, Lobstercon, portable operating, QRP. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.