BC796D "Clicking" Issue

[PascoagFire]

Hello,

I'm having a problem with my BC796D Bearcat scanner. Trunked systems and conventional channels all sound great, but if I try to scan a trunked bank and a conventional bank at the same time, there is an annoying "clicking" sound coming through the speaker every time the scanner switches from conventional to trunked and back to conventional again. It is similar to the sound you'd hear if you plug an input into a stereo while the stereo is on. Any ideas what this may be and if it can be fixed? I'm trying to set up an online feed but this sound is quickly making it unlistenable. I have the feed currently running if hearing it will help diagnose the problem, it is here: Burrillville Fire and EMS Live Scanner Audio Feed

Thanks for any help!

[doctordialtone]

This may or not be the fix. There was no traffic on the feed, so I couldn't hear what you're talking about.

I've noticed that when I use the output to feed amplified speakers, there was a "pounding noise", so I used an old paging transformer to isolate the output. I built the transformer into a pill bottle, making a compact in-line filter. I think you get the idea.

This information comes from another post:
"You might try adding an isolation transformer between the radio audio and the input to the sound card. Radio Shack Part # 273-1374 (1:1 turns ratio audio isolation transformer)."

Does the clicking occur through the speaker on the scanner, or just when the output is connected to your sound card?

I'm sure now that I have started the discussion, a vigorous discussion and debate will ensue over the next several months, about part numbers, specifications, ground loops, sound cards, firmware, software, mini connectors, solder and shielded cable.

Hey, that's why we're here, right?

Good luck.

[PascoagFire]

Doctordialtone, thanks for the reply.

The noise is audible on my feed, even if there is no radio traffic. It happens once about every two seconds. It almost sounds like a slow heartbeat. It is audible through the scanner's speaker even when not hooked up to an external audio source, so it is something internal to the scanner. I'm not sure how the mechanics of trunking work in a scanner, but the noise happens whenever the scanner switches from trunked to conventional or back again, so it has something to do with that somehow.

[doctordialtone]

I hear it now. I couldn't hear it yesterday over the 17 cooling fans in my room and the 2 neighbors running leaf blowers.

Still, it's rather low in volume, though I have not heard how well the actual scanner traffic drowns it out.

I'm sorry - that may be something inherent.

If you want, I'll send these guys with the leaf blowers over so you won't have to hear it?

Good luck!

[PascoagFire]

Thanks. I'm actually going to shut the trunked bank off for now until I figure it out.

I actually could use those guys with the leaf blowers over here, my yard is still a mess!

[W9NES]

I own 2 Uniden 796d"s and do not have that problem. When I am monitoring two systems my scanners are very quiet and both are running a ext. speaker.

[ka3jjz]

There is a mod in the wiki for the popping/clicking - wonder if this would help at all..

Fix Audio Popping on the 785/796 - The RadioReference Wiki

Mike