[GreenKeys] Re: M20-RO

[Charles Ring, W3NU]

Chuck Swiger wrote:

> >And more from memory, so if I am wrong on a detail or two,
> >someone add to this.  I think the basic AP Lenkurt system was
> >a 16 channel AFSK multiplex system, that would allow 16 channels
> >of data on a voice grade phone line.
>
> Gang - just curious, is this anything like FDM signals on shortwave?
>
>  From what little I've picked up thru the years there are or used to be
> 'buzzsaw' sounding signals that were reportedly multiplex feeds - has anyone
> here ever decoded those?

I listened across the UPI line (same Lenkurt system as AP) at the radio station
I worked for, and it didn't sound at all like a buzzsaw, just a number of AFSK
signals with different mark and space tones all mixed together.