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Portable usage in police agencies

Posted: Wed Oct 18, 2017 9:30 pm
by Bill_G
Tell me about how your local PD's use their portables.

I chased down a long standing complaint in a small agency this week - echo in the radios after recent installation of voting receiver installation. It's a growing city along the Columbia River experiencing coverage issues particularly by portables. The sales department solution was adding two satellite receivers and a compartor. Good, old school stuff.

The primary repeater has a 4W phone line. One receiver uses a DS0 over a T1 through an existing microwave. The third site uses Multitech IP modems over DSL. Our tech got it all working perfectly including compensating for the delay introduced by the DSL. However, the officers still reported hearing delay in the repeat audio particularly at night. Our tech never heard it himself, but the problem got escalated when dispatch started experiencing the same issues overnight.

It turns out the officers have their portable lashed to their belt with an earpiece plugged in all the time. Dispatch keeps portables on their desk at night turned up to confirm their transmissions went out. Both groups hear the delay between their outgoing and the repeated audio, and are calling that "echo".

Obviously, there is nothing I could do about the 200ms delay. It's necessary to sync the DSL with the other audio. But, it took some listening to understand how they use their radios to discover the problem. Do your people do the same thing? Has it become SOP to keep portables turned up?

Portable Usage In Police Agencies

Posted: Thu Oct 19, 2017 2:35 am
by Jim1348
Bill_G wrote:Tell me about how your local PD's use their portables...Do your people do the same thing? Has it become SOP to keep portables turned up?


Some do and some don't. The earpieces are popular in some places and not so much in others. Honestly, it has a lot to do with what the culture is where and where you start/work. And, there are also all sorts of other variations. A PD near me never had scanning on either their portables or mobiles. So, many guys/gals kept the car radio on the dispatch channel/talkgroup and the portable on, in the car, on the car-to-car channel/talkgroup.

When I was still a deputy sheriff, I was on county radio, but often in places dispatched by their own PSAP. So, I, too, would sometimes keep my car radio on county main and the portable on that agencies main. Even with scanning on conventional, there is still nothing quite like keeping a radio selected on that channel /talkgroup.

I even had a Yaesu dual band rig in my unmarked car. It, too, was handy in any number of ways!

Re: Portable usage in police agencies

Posted: Thu Oct 19, 2017 4:58 am
by SteveC0625
Our dispatch center, modest in size - 1.3 million calls per year, only used portables on the dispatch floor for trainers to monitor their trainees late in their FTO time.

We had one permanent monitor receiver on county fire and one on city fire connected to one of the slots on the consoles so that the dispatchers there would always know that QC-II tones and initial voice message went out properly. There was no echo effect as it was all analog conventional at the time. (The receivers were just old L03's with external antennas on the roof, but reliable workhorses for sure.)

They're moving to a P25 700Mhz system now so what they're up to today is unknown.

Re: Portable usage in police agencies

Posted: Thu Oct 19, 2017 5:13 am
by Bill_G
SteveC0625 wrote:Our dispatch center, modest in size - 1.3 million calls per year, only used portables on the dispatch floor for trainers to monitor their trainees late in their FTO time.

We had one permanent monitor receiver on county fire and one on city fire connected to one of the slots on the consoles so that the dispatchers there would always know that QC-II tones and initial voice message went out properly. There was no echo effect as it was all analog conventional at the time. (The receivers were just old L03's with external antennas on the roof, but reliable workhorses for sure.)

They're moving to a P25 700Mhz system now so what they're up to today is unknown.


They will experience about a 1-2-3 delay. (the period of time for three syllables) Depends on the backhaul.

Re: Portable Usage In Police Agencies

Posted: Thu Oct 19, 2017 5:22 am
by Bill_G
Jim1348 wrote:
Bill_G wrote:Tell me about how your local PD's use their portables...Do your people do the same thing? Has it become SOP to keep portables turned up?


Some do and some don't. The earpieces are popular in some places and not so much in others. Honestly, it has a lot to do with what the culture is where and where you start/work. And, there are also all sorts of other variations. A PD near me never had scanning on either their portables or mobiles. So, many guys/gals kept the car radio on the dispatch channel/talkgroup and the portable on, in the car, on the car-to-car channel/talkgroup.

When I was still a deputy sheriff, I was on county radio, but often in places dispatched by their own PSAP. So, I, too, would sometimes keep my car radio on county main and the portable on that agencies main. Even with scanning on conventional, there is still nothing quite like keeping a radio selected on that channel /talkgroup.

I even had a Yaesu dual band rig in my unmarked car. It, too, was handy in any number of ways!


I figured it had something to do with their belt. The portable is lashed down with the earpiece cable threaded through their uniform. It becomes a Borg implant. Always on, always talking in their head. Unfortunately, they are just going to have to turn the volume down when they are in the car.

Re: Portable usage in police agencies

Posted: Fri Oct 20, 2017 5:03 am
by Bill_G
I'm getting sense it's not unusual behavior, but it's not standard behavior. ie: not every agency does it.

Re: Portable usage in police agencies

Posted: Fri Oct 20, 2017 10:13 am
by alex
I have another solution. As opposed to them listening why don't you setup on the console a COR light off a receiver on the same channel. That way if the dispatcher sees an indicator when the radio is transmitting they know the repeater is online? That would solve the echo problem of them having a portable with an ear piece.

The other issue we have up here is people get used to the old systems which run in near-real time. It is hard to explain to the fire fighter, police officer, etc,. why there is now a 1/4 second delay. It wasn't there before... I thought technology was better... etc.

Re: Portable usage in police agencies

Posted: Sat Oct 21, 2017 6:31 am
by Bill_G
The delay in DMR and/or ip backbone systems has been an issue from day one. Rail crews and ship loading crews have stayed analog radio for safety reasons. When you're trying to switch a track, or swing a crane, I get it - you need instant communications. But, dispatching doesn't. Everyone eventually gets used to it.

Re: Portable usage in police agencies

Posted: Sat Oct 21, 2017 7:23 am
by alex
Bill_G wrote:The delay in DMR and/or ip backbone systems has been an issue from day one. Rail crews and ship loading crews have stayed analog radio for safety reasons. When you're trying to switch a track, or swing a crane, I get it - you need instant communications. But, dispatching doesn't. Everyone eventually gets used to it.


I heard a same/similar story long ago from Jason on here that had to with the Disney parade when they switched to Nextel/iDEN and took away the analog radio. They had some incidents where floats wouldn't get the word stop on time and had to go back to analog to resolve the timing issue.

Re: Portable usage in police agencies

Posted: Sat Oct 21, 2017 8:33 am
by Bill_G
alex wrote:I heard a same/similar story long ago from Jason on here that had to with the Disney parade when they switched to Nextel/iDEN and took away the analog radio. They had some incidents where floats wouldn't get the word stop on time and had to go back to analog to resolve the timing issue.


We had a whole crew of dock workers walk off the job because of Trbo delay. We had to switch them back to analog repeater. A steel mill charge crane (the guy that drops the material into the smelter) had similar problems, but we changed them back before it became a work safety issue. It's SOP now to always program some simplex analog channels in new Trbo systems.

Re: Portable usage in police agencies

Posted: Sat Oct 21, 2017 12:14 pm
by RFguy
Bill_G wrote:It's SOP now to always program some simplex analog channels in new Trbo systems.


Interesting as our SOP is to never give them an analog channel for direct, to keep it digital.

I'm speaking of non-critical users here (shopping malls and the like). They get used to digital and if they have a fall back to analog, they use it as a crutch to avoid learning to adjust to digital quality.

Your applications are different.

Re: Portable usage in police agencies

Posted: Sun Oct 22, 2017 12:35 pm
by joescanner
Bill_G wrote:I'm getting sense it's not unusual behavior, but it's not standard behavior. ie: not every agency does it.


Meh, you've got at least one other customer where it's the norm instead of the exception.

Re: Portable usage in police agencies

Posted: Thu Dec 21, 2017 11:53 am
by Karl NVW
FWIW, users get the same so-called "Echo" delay in P25 systems, and for precisely the same reason - delays in the infrastructure transport path. Strange how the laws of physics are so repeatable.