SDS200 Digital Audio Cut Off

vcrtech

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Hello all, I'm not sure if this is an issue with the P25 radio system in the area still being new and/or built out, or an issue with the SDS200. At times, I will notice the end of a transmission is unmistakably cut off, and when someone else transmits in the same talkgroup, I will hear the last bit of the person cut off right before the next person speaks. Has anyone else experienced this? The best way I could describe it would be.....

Person1 UID on TG 5: "Hello, how is everybo".....*2-3 seconds of silence/scanning*..... Person2 UID on TG5: "(Person1 continues) dy.... (Person2) Unit 7 is doing well"

If no one else has experienced this, I'll check other P25 Phase II systems and see if it happens there. It doesn't happen all the time, just randomly.

Thanks for your time in advance!
 

vcrtech

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Sounds like you might have priority on.
Hmm.. It's a hand jammed list into the quick save. I double checked every TG as being set to off for priority. I really do think it's the radio net as none of the others seeeem to do this and they are still building this system out. I just wanted to reach out to see if others have experienced this.
 

tvengr

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Feb 10, 2019
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Check that the scan delay for the talkgroup is not set to a negative value. After the programmed time, the talkgroup will be cut off.
 

W1KNE

Owner ScanNewEngland.
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Two items come to mind for me.
1) Close Call mode is set to PRI, and not OFF or DND.
2) These scanners are known to overload/image issues. The voice or control channel you're on is getting occasionally wiped out by occasional local interference.
Several people here have had improved performance by editing the programmed system's site settings to eliminate the NAC.
 

vcrtech

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Thank you all for your responses! This happens very frequently and I will try all of the above and get back with results and a video of it happening if it is still occurring. I will say the site is pegging the needle in terms of RSSI.
 

Ubbe

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I will say the site is pegging the needle in terms of RSSI.
SDS scanners are a bit sensitive to strong signals and doesn't handle those well. Whenever you see a site that constantly gives a -60dBm RSSI value or stronger like -50dBm, and you might have to enable a RSSI display at the display edit feature, you could add the attenuator setting to that site to avoid any overload problems. The attenuator will reduce the level by 20dB and levels at -80dBm are still noise free to receive.

/Ubbe
 

vcrtech

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SDS scanners are a bit sensitive to strong signals and doesn't handle those well. Whenever you see a site that constantly gives a -60dBm RSSI value or stronger like -50dBm, and you might have to enable a RSSI display at the display edit feature, you could add the attenuator setting to that site to avoid any overload problems. The attenuator will reduce the level by 20dB and levels at -80dBm are still noise free to receive.

/Ubbe
This was it! The RSSI was between -55dBm and -50dBm, and with the attenuator on, the audio is crystal clear without any strange artifacts. Thank you all for your assistance!
 
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