Scanner Frequency Issue

[Ajbrown82]

I have two uniden scanners one is a desktop and one is a portable.

Both scanners have stopped broadcasting Warwick, RI Fire frequencies during the day. The dispatch alert tone sounds and then it is dead air. This happens between 8:30am and 12:30am daily. However, from 12:30am- 8:30am when the dispatch time goes off the dispatch communication follows as normal - this was the previous normal activity. The issue started around June 2024, I am not noticing. Any updates to the channels or frequencies wondering if anyone else has experienced anything similar.

 

[Whiskey3JMC]

I have two uniden scanners one is a desktop and one is a portable.

Specific models please? Welcome to the RR forums

 

[Ajbrown82]

Uniden BC144xl and Uniden BC125At

 

[Ajbrown82]

I have two uniden scanners one is a desktop and one is a portable.

Both scanners have stopped broadcasting Warwick, RI Fire frequencies during the day. The dispatch alert tone sounds and then it is dead air. This happens between 8:30am and 12:30am daily. However, from 12:30am- 8:30am when the dispatch time goes off the dispatch communication follows as normal - this was the previous normal activity. The issue started around June 2024, I am not noticing. Any updates to the channels or frequencies wondering if anyone else has experienced anything similar.

It looks like the could be using 851 frequency during the day and 151 frequency after 10pm. Been doing some research

 

[wa1lad]

800 (RISCON) is used 24/7/365. Their old 153 vocal freq is only used from roughly 10PM to 7 AM.

 

[greggerm]

I heard this in a radio call the other night, in fact...

Dispatch calls out and says "Switching to night radio operations" at 22:00.... RISCON continues to broadcast as usual, but I guess your experience is what they were actually doing... flipping the switch on for the old frequencies. Interesting that they'd fire up the old freq's at night instead of just maintaining use of RISCON.

I have absolutely no real radio frequency physics background, so forgive me if this is common knowledge... Is there some sort of nighttime issue with signals on 800mhz which would encourage them to flip back to VHF? Perhaps allowing for technicians and planned network outages by bringing up the old standby?

 

[wa1lad]

They use the VHF for station alerting only. You will hear tones go over, then the dispatch (usually). The tones turn the lights on in the station and strike the gong as a "wake up" to alert that particular station or piece of apparatus that they have a run. It's simple technology that has been around for decades. If you Google "station alerting" you will get more info on how it works, why its used and the newer IP based station alerting that's out there.

 

[greggerm]

So my follow up question was going to be about why Warwick announces going into nighttime radio ops and what makes it different from daytime if it's about the tones, but here's what I came up with....speculation follows!

In daytime ops, tones go out for all to hear over RISCON, but still probably over VHF for proper alerting. In nighttime ops, crews are allowed to mute down RISCON and they flip to use VHF alerting tones specific to stations. Station 1 gets to sleep while Station 4 gets called into service. RISCON is still used for en-route incident response and fireground and whatnot, but its not the tone out. (?)

I will say - the history and tradition of fire dispatch is quite impressive. Box alarm, still alarm, the tones, bell, no bell... distinct meanings which haven't needed to change in some time...

 

[sefrischling]

So my follow up question was going to be about why Warwick announces going into nighttime radio ops and what makes it different from daytime if it's about the tones, but here's what I came up with....speculation follows!

In daytime ops, tones go out for all to hear over RISCON, but still probably over VHF for proper alerting. In nighttime ops, crews are allowed to mute down RISCON and they flip to use VHF alerting tones specific to stations. Station 1 gets to sleep while Station 4 gets called into service. RISCON is still used for en-route incident response and fireground and whatnot, but its not the tone out. (?)

I will say - the history and tradition of fire dispatch is quite impressive. Box alarm, still alarm, the tones, bell, no bell... distinct meanings which haven't needed to change in some time...

They switch over so when the crews go to sleep, it trips the station to alert to turn on the lights and ring the bell.

This is not needed in the day time.

 

[kl7hny]

So my follow up question was going to be about why Warwick announces going into nighttime radio ops and what makes it different

[mass slippage ensueth]

I will say - the history and tradition of fire dispatch is quite impressive. Box alarm, still alarm, the tones, bell, no bell... distinct meanings which haven't needed to change in some time...

Retired firefighter/paramedic here, from time mostly in Alaska.
In Fairbanks, we had a sign in the firefighters' lounge:
"The Fire Service -- 250 years of tradition, unhampered by progress."

73 de KL7HNY