996XT Not Picking Up Control Channel

[FirePhotog]

I have two 996XT connected to Proscan for remote listening. This system has been working fine for months. Now I no longer pickup control channel of the P25 system I am monitoring. I did the tune to WX check to see if it was a P25 system issue but no luck tuning in the WX channel.

Now My handheld scanner 396 and 436 are programmed using the same database (RR) file and they work fine.

Before anyone asks all firmwares are up to date, squelch is open, etc. I if I tune to a conventional frequencie I can hear static, so the speaker works. The scanner is mounted on a shelf so there is no risk of vibration or movement to the antenna or connectors.

Do scanners just "go bad" out of random? What would cause the scanner to stop receiving any transmission?

I spent hours searching the RR forums looking for a solution before I posted this. There are about a dozen similar posts to mine but no real solution.

Any help would be great,
Thanks!

 

[JamesO]

Yes the 996 and possibly the 396 models can have the receiver section fail. The question is did one of your 996's receiver fail without you being aware and then the other fail at some point later?

Did both radios fail at the same time?

Did the receiver/front end get damaged on theses scanners fail due a near field transmitter or lightening strike?

The 996 receivers that I have seen fail tend to not function above 30 MHz, probably a mixer and/or switching stage failed.

You need to check out the remote location for new transmitters and see if these radios work below 30 MHz.

I have a 996XT in for repair at this moment for loss of RX above 30 MHz. Something shorted in the unit and it would not even power up, but after multiple power up attempts on a 12 Volt battery rather than the wall wart, the radio finally quit short cycling and powered up, but had no receive above 30 MHz.

 

[ofd8001]

Not receiving any weather broadcasts is a good indicator of receiver issues. I agree that the most likely causes are a transmitter too close to the receiver/antenna, a lighting strike, or a static electricity spark occurring when the antenna cable was disconnected/connected.

Most likely the problem can be repaired.

https://repair.uniden.com/repairInstruct.cfm

 

[darunimal]

The best thing to do before you ship it back is unscrew 12 philips head screws and look at the antenna connector inside and see if the connection specifically the center pin is still making contact with the main board, but before doing that, I'd be checking the center pin to ground area on the antenna connections and blow out both in case any metal shavings are making a center to ground conductive path (thats bad). Other than squelch or attenuation, it might be time to send for repair after checking those 4 things.

 

[wtp]

could be

lightning. after all florida is known for that.
and the main reason my 396T runs on battery 24/7.
the storms sneak right up on you.