What are the symptoms of bad reception of a simulcast system?

dimab

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I’ve got a BCD325p2 that I know doesn’t handle simulcast systems well. But what should I be hearing/seeing or not hearing when I’m in a bad spot for simulcast reception? I’m listening to CLMRN which is a system in CT, USA that is p25 phase 2 and all the sites I’m interested in are simulcast.
Ive been trying to compare this receiver to my rtl-sdr setup with SDR-Trunk (which is awesome) but not sure I’m hearing any difference. Maybe I’m in a good spot and not having any simulcast issues?
If I travel around, I want to understand when I’m getting good or bad simulcast reception/decoding.
 
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I monitor CLMRN on several scanners

When Simulcast occurs conversations are broken up and you'll miss parts of the conversation.

It depends where you are located as to which transmissions will be affected if any.
 

dimab

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I monitor CLMRN on several scanners

When Simulcast occurs conversations are broken up and you'll miss parts of the conversation.

It depends where you are located as to which transmissions will be affected if any.
When you say “miss” - do you mean the transmission is garbled or the scanner just doesn’t pick up the transmission at all?
 

fredva

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My experience with simulcast on scanners not made for it is that the transmissions will be garbled, or completely missed. Sometimes it can be hard to tell if you are missing transmissions. Comparison to a radio that is receiving transmissions, or realizing that you heard an EMS or fire unit arrive on the scene but never heard the dispatch when you should have, are ways to tell.
 

iMONITOR

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I’ve got a BCD325p2 that I know doesn’t handle simulcast systems well. But what should I be hearing/seeing or not hearing when I’m in a bad spot for simulcast reception? I’m listening to CLMRN which is a system in CT, USA that is p25 phase 2 and all the sites I’m interested in are simulcast.
Ive been trying to compare this receiver to my rtl-sdr setup with SDR-Trunk (which is awesome) but not sure I’m hearing any difference. Maybe I’m in a good spot and not having any simulcast issues?
If I travel around, I want to understand when I’m getting good or bad simulcast reception/decoding.
There are many people here on RR that are 100% convinced you cannot monitor a simulcast system unless you have a Uniden SDS100 or SDS200. You, myself and numerous others have found that not to be true. Without repeating what I've said dozens of times it is in fact possible.

I've had great success with all the current line-up of all Uniden digital scanners. I also had success with Whislter's TRX-1 & TRX-2.

It should be noted I have not had great results while on the move in a vehicle. If you travel around you most likely will not experience satisfactory results, unless you pull over and park, or stay in one place like a motel, etc. Then it's anybody's guess.
 

ofd8001

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"Garble" is the biggest one, like hearing portions of words, missing words, etc. Sometimes you know a talkgroup is active because it is displayed on the scanner, but you do not hear audio.

iMonitor: count your blessings and buy a Powerball ticket. I get good decode on non-SDS scanners maybe half the time and is very location dependent. And I've done a ton of fine tuning with minor improvement.
 

natedawg1604

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Honestly you should consider installing OP25, in my experience it's the best SDR program for simulcast. But like others have said, with non-sds scanners your going to randomly miss parts of conversations. It's very random and sporadic.

I didn't realize what I was missing, until by happenstance I was in mall listening to an older Uniden scanner on earbuds, and overhead a XTS speaker mic of a cop standing near me (on a call not involving me of course lol). I suddenly realized how much I was missing.
 

iMONITOR

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"Garble" is the biggest one, like hearing portions of words, missing words, etc. Sometimes you know a talkgroup is active because it is displayed on the scanner, but you do not hear audio.

iMonitor: count your blessings and buy a Powerball ticket. I get good decode on non-SDS scanners maybe half the time and is very location dependent. And I've done a ton of fine tuning with minor improvement.
I've owned a couple of SDS200's to compare. For my location I'd say the BCD*36HP scanners work about 95% as good for me, and the BCD996P2 about 90% as good when compared to the SDS200. I returned one SDS200 a few years ago, sold my second one. In spite of all this I'm seriously considering the purchase of another SDS200. I'm a hopeless perfectionist so I got to go with the flow! :)
 

danesgs

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I have a GRE-900 a PRO-2096 and a 996P2, only the 2096 on Phase 1 has been garbled on occasion. I listen to Leesburg PD and LCSO at Sterling dispatch and Dulles and they are clear. I would think besides the simulcast issues it really comes down to where you are in regards to the transmitter site. Lots of other factors involved.
 

tvengr

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But what should I be hearing/seeing or not hearing when I’m in a bad spot for simulcast reception?
When not receiving a talkgroup, the control channel frequency should be displayed on the screen. If you have good signal strength and you see NFM or it alternates between NFM and the control channel frequency, that is a good indicator of simulcast distortion.
 

Ubbe

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Uniden scanners will often skip transmissions with bit errors, thinking it is encryption. I see a big difference monitoring in search mode, where Uniden have no encryption detection, and scan mode. I think Uniden should implement a way to let the user disable the skip encryption function to keep the scanner on the channel. It would probably help a lot during difficult interference situations, especially with simulcast issues with a non SDS scanner. It would still be as garbled audio as now but would keep monitoring and probably clear up occasionally during a conversation.

/Ubbe
 
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