From Steven, G7VFY comes news of a very simple 10m DSB transmitter from the blog of KA7OEI. This is an experimental very low power transmitter. It is unlikely to be of use in serious applications, but the range might surprise some. On 10m, the antenna is efficient and on a clear frequency it has the potential to get a long way. Over 1000km would not surprise me on a totally clear frequency. After all, 1mW (or so) is about 53 if a 100W signal was 59+12dB. On 10m such signals with 100W are very possible.
See http://ka7oei.blogspot.co.uk/2014/10/the-pointless-10-meter-dsb-qrp.html .
Hi Roger:
ReplyDeleteYou and your readers may like this 1990 issue of 73 Magazine.
https://archive.org/details/73-magazine-1990-11
I built the fire-ball transmitter featured in this issue 24 years ago and I still have it. I used it with my SONY receiver.
I caused a lot of QRM to my neighborhood's televisions.
In 1991 there was an AM transmitter featured in Nuts and Volts magazine that I built.
Anyone remember this circuit?
When I think about it now it may have been a DSB transmitter.
http://www.qsl.net/n2oto/ttlclk1.jpg
http://www.qsl.net/n2oto/ttlclk2.jpg
Season's Greetings
Thanks Rupert.
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