Idle hands looking for help with an old idea

[Josh380]

So here I am, Thanksgiving weekend, off until Sunday, then I start my vacation Monday, and the part of my brain that likes to tinker with things I probably shouldn't tinker with has got me thinking of something I successfully attempted way back in the 90's. The unfortunate thing is, I can't for the life of me remember how I did it. I know it was fairly simple, and took me less than 20 minutes to complete.

What I wanted to do back then, was simply add echo to my CB. It was one of the old Radio Shack look alike uniden models...analog meter on the left..yada yada. I didn't have the money for an echo board, but I did have access to an echo guitar effect pedal. So I set out to figure out how to wire it to that radio, and 20 minutes later, I had the required input and output for the pedal, on 1/4" connectors, wired to the CB mic jack. I think it required tying the two grounds of the 1/4" connectors to mic ground then simply locating the audio in and out on the radio. but I'm not 100% on that...it was a long time ago.

I'd like to try it again, but this time a little less messy, without the drilling and ugly 1/4" wires hanging out the side of my radio. I'd like to wire it for 4 pin cobra. But this time instead of using just an echo pedal, I'll be using a multi effects processor.

I have a multi-mic box already wired for 4 pin cobra. This box also has three 1/8" (3.5mm) connectors that I can't seem to figure out what they're for. I have no issues about using these connections for my project.

If anyone has any idea how I might accomplish this, please let me know.

 

[Josh380]

Well, give me a day with nothing else to do and no response (I know, it IS Thanksgiving, most of you have families to attend to), and I come up with an idea using some test leads and a guess from a wiring diagram for Cobra mics.

And here we have it. I know it's a mess in there, I had purchased this box for another idea that failed, so most of this isn't my work, and I was sloppy with the ground but it's connected. I also had to cut out a relay that was in there. I think the previous owner had it wired as some sort of unbalanced inputs (one left, one right, one a 5v input I think was for a keying device).

Basically I was correct. Ground is tied together and connected to mic ground/shield. One end, we'll call it the input, is connected to the center pole of one of the 1/8" (3.5mm) mono plugs. The other, we'll call the output, is connected to the other 1/8" (3.5mm) mono plug. Using a 1/8" to 1/4" cable for each end going to the guitar pedal completes the connections, that are otherwise inactive when unplugged.

I wanted to use a guitar effects processor, but I'm having an issue with that all too familiar 60hz buzz from the power supply, which is drowning out any effect whatsoever. I'll try one of those cheapo battery powered effects processors, because it does work with just your standard 9v battery powered effect pedal.