mertzs5
Member
Is there anything I can do to improve the audio of a narrowband signal. Our Sheriff's Department went to narrowband. The signal is good but it sounds all digitized and is often difficult to understand. Thank you.
PSR-800 and Narrowbanding
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Did you try turning the attenuators on and off to see if it made any improvement in signal quality? You could try turn off the digital arc.
Narrow band signals are subject to interference of nearby strong signals that may be near the bandwidth of the target signal frequency.
Narrow band signals are subject to interference of nearby strong signals that may be near the bandwidth of the target signal frequency.
PSR 800 & County
Are you talking about 151.1225? I see where they are also using digital on 155.13 with a NAC of 700. If it is sounding "digitalized", it may very well be digital.
Which one of these frequencies are you talking about when you hear this sound?
Are you talking about 151.1225? I see where they are also using digital on 155.13 with a NAC of 700. If it is sounding "digitalized", it may very well be digital.
Which one of these frequencies are you talking about when you hear this sound?
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mertzs5
Member
155.130 NAC 700
The one I am using is 155.130. Mode is auto and squelch is NAC 700. Can I tweek the squelch or the mode to improve this audio?
The one I am using is 155.130. Mode is auto and squelch is NAC 700. Can I tweek the squelch or the mode to improve this audio?
I just imported that one frequency into my setup to see how it comes in (using EZ Scan) and it comes in as:
- Mode = FM
- Squelch = NAC 700
- DMode = Digital
Waushara County Sheriff went to a full-time P25 VHF conventional simulcast system (Motorola Linear Simulcast Modulation). They previously were using mixed-mode analog & P25 and were NOT simulcasting.
All P25 consumer-grade scanners have difficulty dealing with the signal distortion caused by P25 simulcasting, and Waushara's is worse than most. To monitor Waushara County, I have to use a handheld, holding it horizontally and rotating the radio & antenna until I can null-out all but the Poysippi tower. It is a major pain. I don't think Waushara's radio techs have spent a lot of time adjusting the phasing between transmitter sites, which makes it exponentially worse for us.
Plus Waushara County uses digital encryption most of the time, in addition to the simulcasting.
FWIW, Waupaca County also went to a Tait simulcast P25 conventional system on VHF, but their techs have spent a LOT more time dinking with the phasing delay between the transmit sites. Still not perfect, but a lot better than when it first went on the air.
Most actual P25 transceivers have a setting for LSM - simulcast P25, which allows the radio's DSP to discard the distortion-damaged packets, allowing for a clear receive.
Uniden recently released a firmware update for their scanners that seemed to have helped with receiving Waushara County's P25 simulcasting. Unfortunately, no fix from GRE.
All P25 consumer-grade scanners have difficulty dealing with the signal distortion caused by P25 simulcasting, and Waushara's is worse than most. To monitor Waushara County, I have to use a handheld, holding it horizontally and rotating the radio & antenna until I can null-out all but the Poysippi tower. It is a major pain. I don't think Waushara's radio techs have spent a lot of time adjusting the phasing between transmitter sites, which makes it exponentially worse for us.
Plus Waushara County uses digital encryption most of the time, in addition to the simulcasting.
FWIW, Waupaca County also went to a Tait simulcast P25 conventional system on VHF, but their techs have spent a LOT more time dinking with the phasing delay between the transmit sites. Still not perfect, but a lot better than when it first went on the air.
Most actual P25 transceivers have a setting for LSM - simulcast P25, which allows the radio's DSP to discard the distortion-damaged packets, allowing for a clear receive.
Uniden recently released a firmware update for their scanners that seemed to have helped with receiving Waushara County's P25 simulcasting. Unfortunately, no fix from GRE.
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