536HP constant trunking cut out to control channel

[Anderegg]

I just updated the firmware on my "bottom of an old box" queen 536HP, which I never use. Playing with Siren app and on my local digital 3600 system, the trunking reception cuts back to the control channel randomly every couple of seconds, loosing audio on the channel for 2-3 seconds each time. I heard the audio cutting out on the scanner, but was only able to see the receive channel flipping over to the control channel on the Siren app. Pretty much makes the scanner useless for anything.

The scanner never did this previously, and all forms of priority and Close Call are turned OFF.

What could be doing this? I tried to do a googly search but all i got was ads for Uniden scanners and software.

Paul

 

[Anderegg]

I turned off the Siren app and unplugged the WiFi dongle, and the problem seems to go away. The Siren app was the main reason I bought the 536HP, then they didn't release the Android version for years, then when they did, the speaker and audio output failed on the practically unused scanner, now WiFi (Siren?) causes intermittent reception? Anyone ever heard of this issue? Does this on analog and digital, back of set and distant external antenna connection.

The issue

https://youtu.be/qkl1U4Ekxoo

 

[jonwienke]

Make sure the firmware for the scanner and WiFi dongle are up to date.

 

[Anderegg]

As indicated firmware for the scanner is 1.11.xx what is available today from Sentinel, and WiFi was updated to 7.28 a year ago.

Scanner seems to function normally except when connected to WiFi...the audio/control channel cut out/back occurs on the scanner itself, speaker exhibits same audio cut outs as the Android receiver, so it is not the network connection, and REPLAY is turned off.

Paul

 

[ofd8001]

Wild shot here: review you channels to be sure there are no negative delays, such as -5. A negative delay means the scanner resumes scanner after the time expires even though the transmission may continue.

 

[Ubbe]

Judging by the youtube video the audio breaks up with a lot of bit errors and then goes back to the control channel. The audio are good for a few seconds and then break up again until the bit errors increase and loose the voice channel.

Don't know why this should have anything to do with the siren app. Could you double check?
Don't use auto threshold.

/Ubbe

 

[Anderegg]

I am literally under one of the towers...getting maximum signal...again, the scanner doesn't do this when not connected to WiFi...I thought maybe the WiFi dongle was causing RF interference, but separating the antenna and dongle didn't change anything. My TRX-1 scanner was very prone to RF interference out of my WiFi router, within 3 feet you could hear the puttering on 800 trunking channels from the WiFi traffic! :-O

A secondary test 996T I have sitting around gets 0-2 ERR rate on the same system with back of set antenna.

Paul

 

[Ubbe]

1. Did you try both AP and infrastructure mode?
2. You have the problem even with the 536s Wifi settings to "connection off"?
3. Does the problem appear as soon as you plug in the wifi dongle?
4. Or when you start the siren app?

Testing all this might give a clue.

/Ubbe

 

[Anderegg]

OK, with the WiFi dongle attached, the problem is persistent...as soon as I unjack it out of the USB port, the problem goes away. This is without the app connected, just the hardware attached to the back of the scanner. Issue is present on both scan and when on talkgroup hold.

Paul

 

[W4EMS]

The dongle RF output may be getting into the receive circuit as a harmonic frequency since in close proximity. You have probably tried this but if not use a USB extension cord 4-6 feet long and move the dongle away and see if that resolves the problem.

Or maybe change the IF frequency (I think you can do that, have not tried.

 

[jonwienke]

Yes you can, look at the IFX feature in Sentinel. You can also activate IFX from the keypad.

The USB extension is a good idea, also try ferrites on the cable next to the dongle.

 

[Anderegg]

I've got a couple of 6 foot long USB extensions...I had moved to an external antenna, but we all no how well shielded scanners are!

Paul

 

[Ubbe]

What frequencies do the voice channels have on that 3600 system?
Enter those frequencies as analog conventional and open the squelch and listen to any interferencies.
Then you probably can evaluate the best solution while listening to the interference and moving the dongle and/or putting toriods on the cable.

/Ubbe