BC796D, Make it a REAL line out?

[kb0nly]

Has anyone been able to make the tape/record out jack on this scanner a real line out, so that its not controlled and turned on and off?

The pause at the beginning of every transmission and the CHUNK noise is getting annoying on my feed. And don't say use the speaker jack, if i could i would, but i want to be able to still listen locally and turn the volume all the way down when i walk away.

Maybe take audio off before the volume control so its a constant level? Or does anyone know the component at which the scanner turns the audio on and off to the jack?

There has to be a way. If i had a damn schematic i could do it, but nobody has a service manual or schematic for it.

 

[webstar22]

Many people have asked many times over the years for this. That clunk is annoying but good news on my 996XLT the clunk is gone.

 

[kb0nly]

Ok, i have the solution from another member on here... Give me a day or two and i will get this mod done and tested and post how it was done.

I plan on modifying my 796 and 785 for this!

 

[kb0nly]

Oh it works SOOO nice...

A big thanks goes out to Roger N8CHB for telling me how he accomplished this. For audible proof listen to my Lincoln County MN feed... Thats the modified 796... No CHUNK, no delay, very pleasant audio that i'm listening to on my laptop right now.

Ok so how right??

Take the covers off... See the large connector in the center, J6 with one blue wire at pin 1 and the rest are white? You want to tap off that blue wire.

I flipped mine over and cut the trace feeding the tip contact on the Tape/Record jack then soldered on a jumper from that to the pin 1 of J6, the one with the blue wire.

Optional but also a good idea, i cut the traces on either side of the pin for the ring contact on the jack, the Tape/Record jack is a stereo jack, so i isolated that contact so i can insert a mono or stereo plug and it doesn't matter anymore, also no chance of mixing in the switched audio source either.

This can be done on the BC785D also, and thats my next project as i have a 785 feeding my SD feeds.

 

[kb0nly]

One thing to note, that picture was taking while testing...

I have since replaced the jumper with a piece of shielded cable, RG-174 is what i had on hand so i used it. Just scrap a bit of the coating off the ground foil at each end and solder the braid down to make it a shielded connection.

I can't say changing to the shielded cable changed anything though, so if you did it with just a piece of wire i would say your ok.

 

[kb0nly]

There is another way that it could be done but this worked. You could also follow the trace from the ring contact over to about the center of the board where the electrolytic cap is on the other side feeding that trace from the audio amp, if you removed the cap and tapped on there it would feed both the ring and the tip of the tape/record jack with the same audio and you wouldn't have to cut any traces, just remove one component.

I figured I would do it this way so that if I ever wanted to add a discriminator tap I could use the ring of the tape/record jack to bring out a second connection as well without drilling any holes to add a jack. Then if i ever want to return it to stock i just have to repair the cut traces.

 

[duchee]

great work and great mod.

 

[kb0nly]

Thanks!

 

[LANEWZ]

Wait! How about the mod for the 780 XLT. Can we get fixed audio level on that unit?

 

[kb0nly]

Wait! How about the mod for the 780 XLT. Can we get fixed audio level on that unit?

Most likely, i don't have a 780 to look at but i think its basically the same on that wiring header, the AF to the volume control still comes from the blue wire i think.

 

[Kumba]

Is this at all possible for the 396XT? I've noticed that with my 396XT jacked into my car via the line-out to the car's line-in/aux connector, pressing buttons, turning on/off the backlight, opening squelch on receiving audio, etc.., produces a really audible "pop" sound in the low tonal ranges (i.e., bass). My older 396T doesn't do this as loudly (on that one, it's there, but so quiet you barely hear it), so I figured it's something to do with the 396XT's. The pop sounds very much like the chunking issue that you refer to.

 

[kb0nly]

Is this at all possible for the 396XT? I've noticed that with my 396XT jacked into my car via the line-out to the car's line-in/aux connector, pressing buttons, turning on/off the backlight, opening squelch on receiving audio, etc.., produces a really audible "pop" sound in the low tonal ranges (i.e., bass). My older 396T doesn't do this as loudly (on that one, it's there, but so quiet you barely hear it), so I figured it's something to do with the 396XT's. The pop sounds very much like the chunking issue that you refer to.

Its most likely the same cause, the powering up of the the audio amp. You may be able to get a line out connection in the same way, tapping off before the volume control.

 

[duchee]

that would work.

 

[ka3jjz]

or (at least for the DMA scanners) you could simply add an isolation transformer, as discussed briefly here...it's been mentioned many times in the past...

Uniden DMA FAQ Page 2 - The RadioReference Wiki

73 Mike