Non-Nationwide 5 Channel Trunked, 220 MHz system

[robertw]

Here is a list of Frequencies for a local cab company call sign WPCM914. Don't know what Non-Nationwide 5 Channel Trunked, 220 MHz system is. The question is this system a voice or data system and can it be monitored? If so how?
Frequency StationClass
220.03750 FB6
220.18750 FB6
220.33750 FB6
220.48750 FB6
220.63750 FB6
221.03750 MO
221.18750 MO
221.33750 MO
221.48750 MO
221.63750 MO

 

[INDY72]

Firstly, you'd have to have a scanner that can do the 220 MHz band.....and listen to see if it can even be heard at all (analog/digital)..... then listen to its CC's to see if they are Motorla sounds, or EDACS,......

Currently there are no TrunkTrackers made for that band that I am aware of,... and that band is not openable on the digiscanners as far as I know,.... yet.

 

[N_Jay]

Firstly, you'd have to have a scanner that can do the 220 MHz band.....and listen to see if it can even be heard at all (analog/digital)..... then listen to its CC's to see if they are Motorla sounds, or EDACS,......

Currently there are no TrunkTrackers made for that band that I am aware of,... and that band is not openable on the digiscanners as far as I know,.... yet.

I don't think that Mot or EDACS has anything for 220.
It would most likely be LTR on FM or some old ACSB stuff.

 

[INDY72]

TY for that info.. that makes it iether eventually easier or harder to decipher lol...... if a scanner with LTR , and 220 Trunking is ever made.. that would make it easier.. if its ACSB.....welllll no tracking that.

 

[robertw]

Thanks for the help. I still don't fully understand but have found the following web pages that give some explanation. http://www.hallikainen.org/FCC/FccRules/CiteFind/090721
http://hraunfoss.fcc.gov/edocs_public/attachmatch/DA-04-2100A1.doc
As far as I can tell the system was to be used to provide trunked two-way voice communications via narrowband five kilohertz channels, but no such equipment is currently available that is economically feasible or being technically supported. The is companies that are manufacturing 220 MHz narrowband equipment, but this equipment is not capable of voice communications. Rather, this equipment provides for data communications, such as telemetry and supervisory control and data applications (SCADA).

So I guess the answer is it is most likely data and no you can't monitor it.

 

[EricCottrell]

Hello,

This is likely an ACSSB (Amplitude Companded Single Sideband) trunked system. It will be voice. I have listened to this type of system with a AOR 8600, You need a receiver that will tune SSB. ACSSB uses a form of MPT-1327 trunking but there are no scanners or computer programs to do trunk tracking of the system.

In some locations system operators have taken five adjacent ACSSB channels and turned them into two Super Narrowband FM channels. Here in Boston there is one of these systems that uses Passport LTR trunking. If you have a scanner that can tune the 220 range in 6.25 steps then you can listen to the FM systems. It is possible to trunktrack a Passport LTR system using a computer program.

Repeater outputs are in the 220 to 221 band and repeater inputs are in the 221 to 222 Band.

In New York City Mobex has a Passport LTR system on 217 MHz. I noticed a cab company is very active on the system. 217 MHz is the AMTS band that was originally Marine but was open to Land Mobile in the 1990's.

73 Eric

 

[INDY72]

Thanks for input Eric! Now a lil question.. does the HAM 220 MHz band use similar technology, or is it just NFM/SNFM same as 2 meter and the rest?

 

[kg4ojj]

From the Amateur Radio Relay League's web site: http://www.arrl.org

1.25 Meters (222-225 MHz):

222.0-222.150 Weak-signal modes
222.0-222.025 EME
222.05-222.06 Propagation beacons
222.1 SSB & CW calling frequency
222.10-222.15 Weak-signal CW & SSB
222.15-222.25 Local coordinator's option; weak signal, ACSB, repeater inputs, control
222.25-223.38 FM repeater inputs only
223.40-223.52 FM simplex
223.52-223.64 Digital, packet
223.64-223.70 Links, control
223.71-223.85 Local coordinator's option; FM simplex, packet, repeater outputs
223.85-224.98 Repeater outputs only

Note: The 222 MHz band plan was adopted by the ARRL Board of Directors in July 1991. [/u]

 

[LTR]

Trident's PassPort trunking protocol does this frequency band (217-222MHz) along with Motorola's PassPort radios, the CDM1550LS+ and the HT1250LS+.

 

[nd5y]

I just looked up the emission codes for that license.
4K00J2D & 4K00J3E

4K00 = 4.00 kHz bandwidth
J = Single-sideband, suppressed carrier

2 = A single channel containing quantized or digital information with the use of a modulating sub-carrier (excludes time-division multiplex)
D = Data transmission, telemetry, telecommand

3 = A single channel containing analogue information
E = Telephony (including sound broadcasting)

You would need a SSB receiver to hear it.

Tom

 

[loumaag]

...3 = A single channel containing analogue information
E = Telephony (including sound broadcasting)

You would need a SSB receiver to hear it.

This does not preclude it being a digitial signal. So it also could require a vocoder. Analog information can be digitized and then sent as long as the intent is that it be converted back to analog for communication in accordance with the FCC decisions. Hence a 3E designation can be a digital signal as long as the intelligence being carried is analog voice (or sound broadcast).