Why can't I hear FD tone-outs??

[Jacob99]

Whenever a fire dispatcher send out a call, I hear 4 or 5 clicks and then the dispatcher voice. Is there any way I can hear the tones and beeps, or is that not possible? The frequencies are conventional, by the way.

Thanks!

 

[n5ims]

The actual tone outs are now often sent over data lines to the various stations from the dispatch center. The "tones" are now not even tones, but digital codes sent to the station's computer to let the desired station's computer know to sound the station's alarms and open the speakers to let them hear the dispatch.

They still transmit the audio (but not the actual tones) over the agency's dispatch channel so units that aren't in the station can hear the call and respond quickly.

 

[RKG]

The actual tone outs are now often sent over data lines to the various stations from the dispatch center. The "tones" are now not even tones, but digital codes sent to the station's computer to let the desired station's computer know to sound the station's alarms and open the speakers to let them hear the dispatch.

They still transmit the audio (but not the actual tones) over the agency's dispatch channel so units that aren't in the station can hear the call and respond quickly.

That is one possible explanation. Another is that the QC tones might be being sent without PL.

 

[krokus]

People will be able to help you more, if you tell them what dispatch you are trying to monitor, and what you are using to monitor.

 

[rescue161]

He may be listening to a trunked simulcast of a pager frequency. They do that here. FD dispatch for paging tones is sent on a VHF frequency. You can also monitor FD dispatch on the 800 MHz system, but the tones are not rebroadcast.

 

[Jacob99]

Thanks all for your help so far...

People will be able to help you more, if you tell them what dispatch you are trying to monitor, and what you are using to monitor.

453.30000 KNEE654 RM 192.8 PL WCDC STATION Westshore Central Dispatch Center - Station Alerting FM Fire Dispatch

Westshore Region Scanner Frequencies and Radio Frequency Reference

Regional Fire Channel -- Westshore Central Dispatch Center - Station Alerting

I am using a Pro-197, just got it a few months ago.

 

[W2NJS]

The probable answer to the OP's question has been answered by RKG. It's customary to NOT transmit the PL when the tones are transmitted.

 

[ipfd320]

its not the pl tone your gonna hear but instead its the generation of the tone for the pagers to open up for the beep / steady warning and audio of the call txmitted..here in long island i get the same thing the higher the tone generated the less you will hear it (just like a hearing test) i usually turn up the volume just to see if its actually there and it is...there was alot of tone out changes made here to accomidate different zone dept areas (ie-chiefs-rescue-eng-trucks-general)

 

[CCHLLM]

its not the pl tone your gonna hear but instead its the generation of the tone for the pagers to open up for the beep / steady warning and audio of the call txmitted.

I may be misunderstanding that comment, but I think you missed the point. There are numerous systems that "strip" or disable the TX PL from the carrier when transmitting the paging tones. Since the PL tones and the QC tones are close in frequency range, this is done to keep the PL tone from mixing with the QC tones in the receiver audio and causing the pager to fail to respond.

Not all pagers are created equal, and some receiver audio sections don't resolve the audio well enough to discriminate the actual tone from the rest of the audio, so "stripping" the PL solves the problem. The result is that if you have PL enabled on that channel on your receiver, you don't hear the QC tones.

Not all receivers are created equal either, and one characteristic of some scanners and cheaper radios when PL is enabled on a channel where the PL is stripped during paging is a ticking noise at the beginning and end of each tone. The reason that occurs goes back to that inability to resolve the audio well enough coupled with the fact that the paging tones are several times the level of the PL tone, thus causing the audio/squelch circuit a little grief. It's not harmful, it just is what it is, as is the aforementioned low audio during tones, especially the higher ones, and especially when the tone levels are high enough to cause the receiver audio to clip the tones.

None of this means this effect is what the OP is actually hearing, it just means it is one of several possibilities.

 

[ipfd320]

ok i understand what your saying on this.It could be that i did misread it wrong-Thanks for the learning session its definately something to keep in mind

 

[ab8sn]

I notice this also when I'm monitoring but I also run CTCSS/DCS. I catch the first part of the tones and then the scanner returns to scanning until they dispatch the call. When I turn CTCSS/DCS off everything is fine.

73s

Chad

 

[cdknapp]

My local city department decided to use the digital paging system that they have instead the conventional tone out via thier VHF dispatch frequency. With that, the tones over the conventional system went away. I don't know if that's a possibility in your case or not.
Another possibility may be your PL tone settings. Do you have the PL tones (if any) set for that frequency? It shouldn't make any difference if you don't have them programmed, but if you do, and they're not correct, that would cause a problem.
Good luck!

 

[kennyloatman]

I which I could get rid of the annoying tone outs on my conventional systems. I would rather just listen to the stations being dispatched. Personal preference. I could just set the scanner alert on the channel if I wanted a extra attention grabber which would be much shorter and less annoying. I am not familiar with a Pro-197 but maybe that would be an option for you also.