Early in 2010 Steve G0XAR and Hans G0UPL produced a inexpensive QRSS Transmitter kit that allowed many hams worldwide to put a signal on the air. There were actually 3 different transmitters, One for 80,40, and 30 Meters. You had to tell them your call sign when ordering and it was preprogrammed into the keyer microprocessor. They all work very well and are very popular. I hear a new version is about to be released. Like most things in the kit world, there are many modifications devised by other cleaver Amateurs. I have two of these transmitters presently on the air and am almost ready to build an 80M model by gathering up a few more parts. (I had the PC board only for the 80M transmitter). They came with a instruction sheet and could easily be built in an evening. The more popular modifications are W4HBK's crystal heater, ZL2UJG 12VDC power modification for the final Amplifier, and N0QHB's Keyer modification that sends the callsign keying out in precise 10 minute intervals. (this allows it to be "stacked" allowing signal detection at very low transmitter power outputs) The new transmitters signals started popping up on grabbers all over the world and it seems that every week there is a new Station to QSL that you have received their signal. I am not sure how many transmitters Hans and Steve have sold but from the increased traffic on the grabbers I believe, It was a bunch.

The above transmitter is the way I packaged my 30M QRP Labs Kit. The hobby board to the right is how I solved the 12VDC and 5VDC power supply by making the 5VDC supply using a 7805 voltage regulator off the 12VDC supply. Mine also has the W4HBK crystal heater modification hidden under the blob of hot melt glue with the green indicator LED peeking out the top of the blob. I did install the ZL2UJG 12Volt final amplifier modification and the Keyer Chip is the N0QBH 12F629 PIC keyer chip. The transmitter puts out about 350mW maximum power before the 2N7000 FET final starts to get warm to the touch. With a heat sink on it, you can probably get more power, but I didn't want to push it.


This Grabber stacked image says it all. It is a stack of a 40mW signal from Las Cruces, NM to W4HBK's Grabber in Pensacola, FL. It was 4 hours of stacking the 10 minute grabber images. My signal is rock solid in in frequency and the repeating of the WA5DJJ call sign is spot on the 10 minute interval. I built this transmitter to perform some upcoming very low transmitted power tests using FSKCW modulation. I had to make the signal "stackable" if I was going to achieve the very low signal transmitting tests and have them received.

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