MTA Operations Frequency 160.455

[gatekeep]

I was monitoring the MTA Operations channel this evening due to some interesting traffic, and I noticed that I was missing half the conversations...

Does anyone know why the MTA is using 2 PL codes? 151.4 and 114.8? (On the same frequency for the same conversation.)

By the way, if it helps, I'm in Suffolk County.

 

[Spec]

MTA PD East Region

Try this it may help[ you out some.
http://www.radioreference.com/modules.php?name=RR&aid=864

There are a number of number of reasons for it being that way. This board does not have enough band space to go in to all the reasons (lol). Not to worry though... the MTA is in the process of installing a new 800 digital system at all the stations and along the railroad.

 

[CW1NY3478]

Trains???

is the LIRR trains also going 800megs or police only

also is it apco 25 compliant?????

 

[SCANdal]

Will be a part of the SWN OpenSky system

is it apco 25 compliant??

No, it won't be.

 

[Spec]

New 800 system

The Operations Dept (trains) will remain on their VHF frequencies however the the PD and management will have a Enhanced PDA and Reporting network. It will take the place of the communications system presently used to communicate with HQ (PD) and the MDT's in the cars as I'm told.

 

[CW1NY3478]

Mode Of Tx???

what type of mode will it be apco 25, imbe???

 

[Firerescue3120]

I was monitoring the MTA Operations channel this evening due to some interesting traffic, and I noticed that I was missing half the conversations...

Does anyone know why the MTA is using 2 PL codes? 151.4 and 114.8? (On the same frequency for the same conversation.)

By the way, if it helps, I'm in Suffolk County.

Bryan,

The reason they're are two different PL tones is simple. One is for the cars, and one is for the base. Should you take off the PL, you will hear both sides of the conversation (Only if you have a large antenna thought, the cars have no vehicle repeaters.) They're are no vehicle repeaters. So it'll be hard to hear them without a discone antenna or something to that affect.

Good luck.

 

[SCANdal]

Do we know what a vehicle repeater does?

3120,

If the cars did have vehicle repeaters, would Bryan be more likely to hear them?

Also, the original question was still not answered. Why are the cars transmitting with tone 151.4 and the base transmitting with tone 114.8?

SCANdal

 

[Spec]

MTA vehicle repeaters

Yes, they do have them in some of the units. UHF to the RMP. I couldn't begin to tell some of the strange logic that goes out the in the East Region to answer the PL question.

Spec

 

[gatekeep]

I want to know what strange logic, brings a radio shop to decide to make the transmit and recieve PL's for the mobile and base different like that? I would assume you wouldn't want to cut off unit-to-unit communication on the operations/base channels like that incase of emergancy, that is about the only reason I can imagine why there would be 2 different PL's.

But like SCANdal said, the question still hasn't been answered.

 

[DaveNF2G]

Actually, that very reason is not unheard of in other parts of the state. When repeaters first came into vogue, Monroe County Sheriff Al Skinner forbade the dispatch center from turning them on except during specific situations. If he ever heard another mobile unit from his car, he was known to yell over the radio, "Turn that blasted three-way off!"

The New York State Police don't use repeaters, either. There is a specific channel assigned for car-to-car traffic and, as it is simplex, only Troopers who are close enough to each other to have something official to discuss can make use of it. (Lately the NYSP are being dispatched by local counties via their repeaterized radio systems, so at least some of the Troopers will know what repeaters are like before they move to SWN.)

 

[Spec]

MTA PL's

As Dave has stated it is not uncommon in different parts of the state. I agree with you to a certain extent however as you are not aware of the channel plan and useage of this agency, but it does work in fact. Leave it said it works. If you travel from the East region to the North region the channel plan / useage changes completely. The system was designed for that specific area at point in time that required it be set up that way. Operating within a confined frequency range often creates adjacent channel splatter. With number of units in the field the quick fix usually is a PL. I can hit the field with a laptop and change a district in one days time. Now to add some confusion the North does not transmit a PL on the bases, but is PL protected on the recieve side. Drop the PL and you have a car - car frequency without disturbing the base. Use the PL's to create better channel useage. The system is being used less and less as many of the patrols use NEXTEL with group and individual setups. As I said before the 700 - 800 system IS being installed as we speak. A good possibility it will be OPEN SKY. This will remain to be seen when it is completed. The plan is for a secure seamless dispatch and report system. Room for different departments within the MTA (not NYC transit) commuter rails. Don't expect too see any changes within the VHF system. With more than couple of decades working with the system the only thing that changed was a few PL's with newer radios. Nothing is set in stone with this agency until the equipment is turned on, and then they often change mid stream.

 

[DaveNF2G]

It occurs to me that NYSDOT is another case in point - they re-use frequencies on low band by using different PLs, and not only are bases and mobiles often on different frequencies, but they use different PLs as well.

Taxi companies are another example of deliberately keeping mobiles from hearing each other talk to the dispatcher. They do it by using frequency pairs, but the effect is the same. When they go trunked on LTR systems, each car might have its own talkgroup in order to duplicate the two-frequency simplex isolation of mobiles. I've even encountered a local school district that has assigned an LTR talkgroup to each individual bus!

 

[zerg901]

I take that 160.445 is a simplex channel - meaning that the dispatcher and the field units all transmit and receive on 160.445. If the field units cant hear each other, then I guess they would never get a speaker full of static from a unit at the fringe of their listening range. Seems to be a good news / bad news kind of thing - field units cant hear other field units, but field units dont get static from other field units.

Note - when I mention "field units", I am speaking of portable radios and mobile radios.

Peter Sz

(I wonder who the MTA is