3 ms·
Your "2.3KHz of bandwidth" is caused by using a wide SSB filter to send a relatively narrow shift of 170Hz. You equally could have used a narrower filter.
by Johnythree 3y ago
Your "2.3KHz of bandwidth" is caused by using a wide SSB filter to send a relatively narrow shift of 170Hz.
You equally could have used a narrower filter.
- Animats 3y agoPre-single-sideband suppressed carrier systems used an AM carrier, so there really were two audio tones. It's also possible to send FSK over FM, which was often done on VHF where there's more room. Before everything went digital, this sort of thing tended to involve a chain of analog processing stages.
- Johnythree 3y agoHams sometimes used Audio Frequency Shift tones modulated on to an AM carrier as a temporary way of getting on air with an old style AM transmitter. Which of course meant two sets of sidebands (eg four in total) and a excessively wide signal.. But any of the better quality transmitters (Ham, Commercial or military) used pure FSK directly.