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A comment on Turn Raspberry Pi’s GPIO into an FM Transmitter. Parent comment

Re:Turn Raspberry Pi’s GPIO into an FM Transmitter by anticensor on Sunday November 13, 2022 @12:59AM (#33580494)
Why not QPSK over VSB like used in broadcast satellites?
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Re:Turn Raspberry Pi’s GPIO into an FM Transmitter by Johnythree on Sunday November 13, 2022 @02:26AM (#33580853)
The problem with QPSK in particular is a loss of phase lock in marginal conditions, or with interference.

It would require higher complexity, with no improvement for marginal signals.

One possible improvement would be "Synchronous AM" (eg 1/2 of a QAM signal) but that will also lose phase lock in weak signal conditions, eg when it is most needed.

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