After a bit of frustration during the building of the multi-vibrator, the initial on-the-air testing of this rig went amazingly well. I got home from work yesterday and finished wiring up the LED and a 5 pF cap for the FSK circuit. My frequency counter showed a nice 5 hz shift. Perfect. And the LED does flash a bit of blue light!
The sun was going down at this point, and I knew that 30 meters would soon be closed. But a quick check showed that the Belgian Grabber of Johan, ON5EX, was still picking up my QRO (20mW) rig. So I figured that this new rig (with around 10 mW) had a good chance of being received in Belgium. It took me a few minutes to spot it, but then I saw it. It was beautiful. Kind of a square wave with skirts, if you know what I mean. About 4 cycles per minute, and right on the freq shown by my counter. Here is a screen shot of the initial reception:
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When the sun is up over Europe you probably should be able to see my signal.
Amazing: On the receive portion of this system we have billions of transistors (certainly millions in Johan's computer, and countless millions more in the internet). But on the transmit side we have only three.
Got a schematic of it?
ReplyDeleteYes Yes! The schematic Bill!
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