Last year, we started devoting one of our monthly meetings to building something. Last year, we built a small keyer kit, and it was an unqualified success. All 20 people who built the kit got it working. This particular kit was a good choice because it offered something for both beginners and old timers (old farts?). It was simple enough for beginners to build, and yielded something that an old time might use.
This year, we’re doing something a bit different. We’re actually doing two kits – one for beginners and one for the more advanced. The reason we’re doing this is that I became enamored with a project in the March/April 2006 QEX, the Pizzicato Pulse Generator.
The Pizzicato generates very low duty cycle waveforms that, as the article points out:
electrically “plucks†a transmission line; by observing the line’s reaction
on an oscilloscope, you can check the line’s length, terminations, and possible defects.
Now you see why this is a project for more advanced users. Although the circuit isn’t a big deal—it consists of an IC, a voltage regulator, and a handful of resistors and capacitors—one needs an oscilloscope to actually use it.
Bruce, KD8APB, and I (mostly KD8APB) have taken the circuit and modified it so that it could be easily built as a kit. For example, instead of using perf board to build the circuit, Bruce laid out a printed circuit board. Instead of a panel-mount rotary switch, we used a PC-mount DIP switch. The cost for the kits will be $15.
I have already built a couple of them, and they go together in less than an hour. We have the parts for 100 units and plan to offer them for sale, in the same way that QRP clubs offer their kits to the general public.
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