Unknown (V.29 fax machine) modem
There are also some that are currently active in a fellow user's State (CA), in which his signals have appeared in part of the government band, 400-420 Mhz. Audio will also follow.
Here is a typical V29 standard QAMQuadrature Amplitude Modulation fax modem that was posted by a person named Lui Gough: https://goughlui.com/wp-content/uploads/2013/02/V29-9600bps-ECM.wav
And here is an audio clip of a stranger one, some of which have actual preambles inside it. Images will follow later.
Alright. MORE news/updates.
The fellows on our discord server have actually found a **possible**, this doesnt mean 100% true fact, ties to ITU v series modems, including this v.29, that is not being used for fax. It is instead being used for trunking voice channels, that are being used over *leased lines*, which then front-end to RFRadio Frequency transmitters spanning the UHFUltra High Frequency (300-3000 MHz) band by backhauling.
Once again, this is only a possibility.
To prove this, or at most provide an example, here is a PDF of how it would work aside from Canada's Moose Jaw Police Service that operates such an oddity infrastructure in a similar fashion.
There is also a RadioReference forum topic that has talks about v.32 with ASTRO voice transfer using 14,400 baudBaud (unit symbol Bd) is the unit for symbol rate or modulation rate in symbols per second. with ASTRO's 9600/4800 baudBaud (unit symbol Bd) is the unit for symbol rate or modulation rate in symbols per second. voice controls, as both sum up to the modem's baudBaud (unit symbol Bd) is the unit for symbol rate or modulation rate in symbols per second. speed.
Also, this modem usage could act as a medium for better quality with quite possibly narrower bandwith too, as leased lines are always active and have a fixed monthly fee. Hence the reason why these modems are constant carriers that sound like their "faxing nonsense" over the airwaves. But in reality, its trunking data and voice being transmitted on an FMFrequency Modulation carrier with narrower bandwith and quality.