Questions tagged [rtty]

5 questions
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BFSK with huge spacing, why?

I recently bought one of the classic USB dongles to experiment with SDR. At 460MHz (Europe, CH) I constantly see many digital transmission that use BFSK. What is strange to me is that: the frequency spacing is about 9KHz, instead of the much lower…
MarcoM
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How is a crossed-ellipse display generated from FSK?

What is the algorithm or circuit needed to generate a (vintage?, retro?) crossed-ellipse display from RTTY and/or 2FSK signals? (as per the (obsolete?) questions in some FCC exam pool) (assume already down-converted from HF RF to either/or a…
hotpaw2
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Open Source Library for Digital Mode

I want to play a bit more with programming side of digital modes. However, a quick Google search turned up lots of software and some general explanations but no open-source library implementing such a code. For example, I would find a library that…
Edgar H
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What is the proper spacing away from a rare RTTY station?

How far away should I transmit from a rare DX station in RTTY? RTTY itself doesn't take that much bandwidth, but I've heard that I should be spaced 2-3 kHz away. Is that true? Thanks!
PearsonArtPhoto
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How are symbols encoded in RTTY?

I am looking for RTTY AFSK specifications. I am a little confused when coding the Baudot code; not the normal characters, but the symbols and numbers.