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I thought it was just me,but yes there is defiantly a difference in the volume, 154 is louder.
FDNY UHF Dispatch
- Thread starter tbendick
- Start date
I really don't know the technical part of this, but I have had the FDNY UHF boro frequencies programmed in for some time and they work OK.
I see discussion of the PL, is this how you would receive the "mobile frequency" as we called it with VHF? Example: 154.37 Bklyn Base, 153.95 Bklyn Mobile. Would you enter another frequency with, or use the PL number to somehow convert the main frequency.
Or is rcvg the mobile impossible with my scanner? I use a Uniden BC72XLT handheld.
Thanks
I see discussion of the PL, is this how you would receive the "mobile frequency" as we called it with VHF? Example: 154.37 Bklyn Base, 153.95 Bklyn Mobile. Would you enter another frequency with, or use the PL number to somehow convert the main frequency.
Or is rcvg the mobile impossible with my scanner? I use a Uniden BC72XLT handheld.
Thanks
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PL (a trademark of Motorola) has nothing to do with the base or mobile transmit frequencies. PL, as commonly used, is a subaudible tone that is transmitted along with...or "under"... the voice content.
The practice is most often used to enable listeners to screen out unwanted transmissions. For example, if radio networks A and B shared a frequency, network A could set up all of its receivers to remain silent unless a specified subaudible tone, used by all of the transmitters in network A, was present. That way, all of the network A personnel would not have to listen to chatter from network B's units. Presumably, network B would transmit either no tone or some other tone.
As to the "mobile frequencies" being used by FDNY I believe, but do not know for sure, that they are up 3MHz from each base frequency. e.g.: Brooklyn's mobile frequency would be 482.0187 +3 = 485.0187. Please take a listen and let me know if I am right on this.
A final thought... a common misconception is that you must use a PL capable receiver in order to receive transmissions from a network using PL. Not so. If your receiver does not have PL capabilities you can still hear everything that goes out over the desired frequency. You will just be unable to screen out unwanted chatter from other users of the same freq. or channel. Even thought the trademarked initials stand for "Private Line", there's really nothing private about it. It just makes the listener's radio quieter, so that he might "think" he has a private channel.
The practice is most often used to enable listeners to screen out unwanted transmissions. For example, if radio networks A and B shared a frequency, network A could set up all of its receivers to remain silent unless a specified subaudible tone, used by all of the transmitters in network A, was present. That way, all of the network A personnel would not have to listen to chatter from network B's units. Presumably, network B would transmit either no tone or some other tone.
As to the "mobile frequencies" being used by FDNY I believe, but do not know for sure, that they are up 3MHz from each base frequency. e.g.: Brooklyn's mobile frequency would be 482.0187 +3 = 485.0187. Please take a listen and let me know if I am right on this.
A final thought... a common misconception is that you must use a PL capable receiver in order to receive transmissions from a network using PL. Not so. If your receiver does not have PL capabilities you can still hear everything that goes out over the desired frequency. You will just be unable to screen out unwanted chatter from other users of the same freq. or channel. Even thought the trademarked initials stand for "Private Line", there's really nothing private about it. It just makes the listener's radio quieter, so that he might "think" he has a private channel.
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FD347 said:
Exactly as you phrased it, yes. A WBFM receiver would have trouble with a NBFM signal. 100% modulation is reached when the transmitted signal occupies a channel just equal to the bandwidth for which the receiver is designed.
But I think the problem is that they simply don't have the transmit audio gain control cranked up enough on the UHF transmitter.
Anybody got a screwdriver? Whoops. Never mind. I once almost got hooked up for "modifying" department property. (That's how I got sent from S.I. to Brooklyn).
"811", just to add w/"bklyndisp54" and "FD347", the inbound frequency for say Manhattan on 154.25 is 154.01 mhz. If you're in the area, and put in that 154.01 you can hear the mobile units calling in without it going through the repeater. When the dispatcher says "Mixer Off", that's when only 154.01 would heard. I believe this has been mentioned before on this site. And I'm sure in much more detail.
In regards to the newer UHF Channels, I've heard numerous other depts on UHF(450-480 mhz), and I would say, generally speaking, UHF does seem to have a little less volume. Also the signal may not reach the distance that the high band did.
Whenever I traveled to cities like Hartford or Providence, I could pick up the fire dept on the high band (154....mhz) much farther away than the Police depts which used Ultrahigh Bands (450-480 mhz).
The BIG THING that I'm glad the FDNY didn't do is go to Digital, which seems to be a trend in many places. For a buff its a nighmare. Espically those who are not too kool with using this new high tech stuff. Just as an example, I used to pick up Providence Fire at my home 50 miles away on 154.37 mhz. They now went to Digital. I no longer can pick it up at my home, PLUS, I had to buy a new $500.00 portable scanner, have it programmed for $50.00, and buy a new mobile antenna for about $80.00. My Biggest expense since I first started buffing as a kid many decades ago. All to be able to hear the Providence FD when I make a trip up there. Some places have gone to Digital Encryped. That's even Worse. Then no matter what, you can't listen.
I'm just glad FDNY hasn't taken "those steps".
In regards to the newer UHF Channels, I've heard numerous other depts on UHF(450-480 mhz), and I would say, generally speaking, UHF does seem to have a little less volume. Also the signal may not reach the distance that the high band did.
Whenever I traveled to cities like Hartford or Providence, I could pick up the fire dept on the high band (154....mhz) much farther away than the Police depts which used Ultrahigh Bands (450-480 mhz).
The BIG THING that I'm glad the FDNY didn't do is go to Digital, which seems to be a trend in many places. For a buff its a nighmare. Espically those who are not too kool with using this new high tech stuff. Just as an example, I used to pick up Providence Fire at my home 50 miles away on 154.37 mhz. They now went to Digital. I no longer can pick it up at my home, PLUS, I had to buy a new $500.00 portable scanner, have it programmed for $50.00, and buy a new mobile antenna for about $80.00. My Biggest expense since I first started buffing as a kid many decades ago. All to be able to hear the Providence FD when I make a trip up there. Some places have gone to Digital Encryped. That's even Worse. Then no matter what, you can't listen.
I'm just glad FDNY hasn't taken "those steps".
bklyndisp54 said:
Thanks Tony, The idea of a mobile frequency on FDNY UHF is uncertain right now since the rigs are still VHF equipped, what we hear on the FDNY UHF is just simulcast from the boros. Once the rigs switch over to UHF, then will see if the +3MHz works as the apparatus "mobile".
Also your definition of PL is as I understood it ages ago.
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FD347 said:
And I suppose you'll tell me next that everything is solid state...with no tubes in the finals!