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Unknown Trunking System ???

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millam

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Here in SE Alabama I am seeing a lot of activity on 220-222 mhz. The info that I have seen says that those
freqs were taken from the ham bands and were supposed to be used by business for ACSSB (amplified condensed(?) single side band) trunking. There are a lot of 1 and 2 sec burst burst of data. Listening with AM and NFM has no signal heard. Using USB and DRM I can hear data spurts. I can see strings of data every so often. Is this some sort of trunking? Google mentioned DTL (distributed trunking logic) in a couple of places. The FCC database for 220.8675 shows some lic. but none close to me. Just curious.

Mil

Forget, could it be Ham's using the same freqs as shared with business?
 

SCPD

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There a was variant of MPT1327 trunking that used ACSB modulation. It isn't compatible with the narrow-FM FFSK modulation found on standard MPT trunking systems. I don't know if that is what you found but it is very rare.
 

lep

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Here in SE Alabama I am seeing a lot of activity on 220-222 mhz. The info that I have seen says that those
freqs were taken from the ham bands and were supposed to be used by business for ACSSB (amplified condensed(?) single side band) trunking. There are a lot of 1 and 2 sec burst burst of data. Listening with AM and NFM has no signal heard. Using USB and DRM I can hear data spurts. I can see strings of data every so often. Is this some sort of trunking?
The "C" is for Compandord, it was described in an article in the magazine QST. It never proved popular and, IMHOP never lived up the claims of the inventors.
 
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