HFU HF Underground
Technical Topics => The RF Workbench => Topic started by: Zazzle on January 06, 2017, 1016 UTC
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Hey!
Argh! There's this idea. It's stuck in my head. Since weeks. And it wants out. Okay. Here we go.
I'm running three CW Beacons by now. I wanna do something with RTTY because it's fun and allows "high" Data rates. It's also easy to build. I can use a PI-Zero, which makes it easy to collect data and send it. So, what to send?
First, I wanted to send such like temperature, humity and - if solar powered - Battery status.
But that one disasterous evening, a friend started to annoy me with 'yer mom'-jokes and I got the idea to store a biiig collection of those jokes on the PI, having it sending them in a loop.
The other idea would involve a GPRS-Modem. I could have the PI fetch E-Mails once a day and send it's text content. The Address would be public and anyone could send greetings and whatever. This sounds pretty much fun. But I need to think about the problem with the SIM card. Thanks to our politicians going nuts about Terrorism it isn't any longer possible to get an "anonymous SIM". Buying a prepaid card now requires to register it in the shop with your ID. Sucks. So I've to check the situation in countries around my own. Means that I've to pay roaming fees. I've to think about.
I'd like to have your feedback on that. :)
Kind greetings,
Zazzle
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One suggestion - PSK31 is much more robust than RTTY. If you can use PSK31, I think you will be much better heard.
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Or jt9 if you really wanted to wring some dx out of it. That would prevent long messages and reduce the potential decodes to only those who run jt9, however. ROS and Olivia modes are good for dx too.
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PSK31 is fairly ubiquitous, and there's a huge number of decoders for it.
Now, if you want to have some fun... Hellschreiber ;D
As long as you have a CPU, you can easily send multiple modes, and switch between them. Which might make for a nice experiment - which gets out better?
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Heyho,
thank for the input. I've to see whether I'll stick to RTTY (easy to build) or whether I go through the efforts of building a PSK31 modulation stage.
I'm still pondering about the frequency to use. I've to admit that I fancy 80m because of the exellent propagation. On the other hand, 80m is noisy with no end. The power it'll take to cross the ocea contradics with the idea to have it entirely powered by solar. Also, the Antenna (likely a Dipole again) is an issue. 80m band means ~20m on each end. The location only allows to put it ~3m above the ground (dry gound, I should mention).
I'll likely go with the 20m band instead.
Opinions? :)
Kind Greetings,
~Zazzle
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It'd be keen to have a dual band beacon, 20m days, 40 or 80 nites.
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It'd be keen to have a dual band beacon, 20m days, 40 or 80 nites.
Well, I already have beacons on 40m, 30m, 11m.