Last autumn I found an interesting rig on the web, the ATS 3B (lightweight, micro-controlled, DDS driven), capable of CW and digital modes at 4 -5 watts output. The manual was a very interesting read and so I decided to purchase the kit directly from Steve, KD1JV. I knew I wouldn’t do too many - if any - activations during the wintertime and so I planned to build the new trx along with a z-match instead.
The rig (6 HF bands which are chosen from small, pluggable filter-boards) is almost entirely built from SMT parts. If you soldered SMT before you shouldn’t have any problems with this one, although the DDS chip and some resistors have been what I’d consider to be the absolute limit for manual soldering. Beside these, all other assembling was smooth, almost easy-going as time went on and best of all: After initial power up the device started to work without errors! The alignment process was quite easy and done using a scope and an rx connected to the soundcard of my laptop and software with waterfall display showing a sound spectrum. To my astonishment it took me much longer to find an Altoids tin here in Germany (finally I was able to get one, but my throat is still burning from all those mints)
Number two on my whish list was a z-match, because I got a lot of positive feedback from people who already were using one. I searched the web and stumbled over a circuit diagram on a Dutch website. Luckily quite a few of the parts needed were already in the “scrapbox”. As the ATS 3B has no built-in SWR indicator I decided to add an SWR bride with LED indicator (by N7VE) to the z-match. The ARRL-DX contest last weekend brought plenty of room to test it and I was able to work a few stations from the US East Coast at 4 - 5 wtts, although operating the z-match can somewhat be tricky (owing to the very sharp dips), I really need to get used to it.
It was quite a while since my last SOTA activation and so I thought today would give a perfect day for an in-field-test of the new setup. I have chosen AL-176 because it’s the closest SOTA reference to my home qth and - being a one point summit - I knew it would become a nice walk. The weather was quite reasonable, overcast, a bit windy though, but still very springlike with temperatures around 14 C. First I set up the fishing pole with the 20m wire antenna inverted L, the same antenna which I am always using on my activations. I plugged the 10 MHz filter board into the ATS 3B, connected the z-match, applied power from a battery case with 10 AA size NiMH cells (taps from 6 to 12V), matched the antenna and started to call CQ. The band wasn’t crowded at all and so I worked only 4 stations, to my amazement only one stn was heard from the UK. After a while I went to 7 MHz and this time a few more stations responded to my call (including UK), although I was only running a single watt at this time.
Well, I think the setup passed the first test and I must say I am very happy with it, although the number of QSO today was far lower than I was used to (but that must not neccessarily have been caused by the new rig, hi). Compared to its size (and weight) it performs extremly well and the rig itself has a lot of functions like a built in jambic keyer, three memories, a frequency read out by display or cw, battery voltage readout, direct frequency input by paddle, rit, xit and quite a few more. I put a picture onto the web for those who are interested:
please excuse the poor labeling of the z-match, had no time yet to draw a solid label.
Many thanks to all who worked me today from DL/AL-176. See you from the next summit!