Yellow Cab radio system in Tallahassee, Florida, Leon county

[BAP]

I know they have a special system where the drivers can only hear dispatch, and not the other drivers. I am wodering is there a way to hear he drivers on the scanner. I only have one frequency listing, and it only hears dispatch. I noticed it says frequency, and one column says input on the listings. Does that have something to do with it? I scan both frequencies but only one picks up, and it's only dispatch.

 

[BAP]

Seems to be a range issue...

I think I figured it out. Seams to be a range issue. I have heard a driver once on the input frequency. Apparently they have to be very close by.

 

[n4voxgill]

The FCC rules used to require this type of operation, I don't know if still required. This is a simplex system so that impacts receiving the taxis, and make sure you do not use ctcss (tone) as the taxis use different tones.

 

[ButchGone]

Tally taxis

I remember years ago in Atlanta the taxis used a two-frequency simplex system where the base was on a 152 MHz freq and the mobiles transmitted on a 157 MHz freq, much the same way the Georgia State Patrol does now on their VHF hi band. There used to actually be a taxi "channel pair" where a specific 152 freq matched the 157 freq. Maybe this helps?
Good luck!

 

[kb2vxa]

Hi BAP and all,

Older taxi radios were set up for semi duplex operation so the drivers couldn't waste time and resources chit chatting among themselves. That means the base transmits on one frequency and receives the cars on another, sort of like a repeater with no link between the receiver and transmitter. (In full duplex mode they're linked.) There is a definate frequency spacing of the pair but I forgot what it is, check an older issue of Police Call (Hughes/Radio Shack) to find out or maybe someone reading this will be kind enough to supply the information.

BTW Butch, there is no such thing as two frequency simplex, see above. Thanks for the partial pairing info, it's a start.

 

[KMA367]

There used to actually be a taxi "channel pair" where a specific 152 freq matched the 157 freq.

I believe the 152/157 split for taxicabs is 5.26 mHz:

152.27 Base / 157.53 Mobile
and then at 15 khz steps up to
152.45 Base / 157.71 Mobile

There are a lot of other services now shoe-horned onto those frequencies, sometimes paired, sometimes simplex.

 

[Al42]

There's no specific split on VHF-hi.

 

[n4voxgill]

Prior to the elimination of most radio services, taxicabs were regulated by FCC rule 90.93. In the frequency table for that rule, frequencies 152.270 to 152.465 could be licensed as base or mobile. In most cases the were licensed for base. Frequeancies 157.530 to 157.725 could only be licensed for mobile use. That gave the offset for duplex of 5 MHz plus change.

Now taxis are lumped in with all other commercial users and all share the same pool.