Installing talkback on a pc66xl

[nickybots110]

Ok I know the answer for this is here somewhere but I can't find it. I know the radio is the same as the cobra 25.
I found on one site that said about just connecting one resistor by the pa jack but it didn't go into enough detail. If anyone could give me detailed instructions on how to do this it would be great. I just installed echo in the radio and talkbalk would make it so much better. Thanks

 

[Tobashadow]

cobra 29 talkback

Exact same mod / exact same pinout

but alot more info on the 29 for it.

Here's some pic's

http://cbradiomagazine.com/April 2007/Adding talkback to your radio.htm

 

[nickybots110]

Thanks alot. I kept searching cobra 25 so I never looked at these.

 

[CBtalker205]

Now I'm no tech but most of the time I use a 100W/ 1 Ohm resister between the PA and Excternal speaker jack inside the radio. I usualy put a switch inline as well so you can turn it of if you want.

 

[jegs]

Now I'm no tech but most of the time I use a 100W/ 1 Ohm resister between the PA and Excternal speaker jack inside the radio. I usualy put a switch inline as well so you can turn it of if you want.

100 ohm/1 watt would work better.

 

[CBtalker205]

Yeah sorry thats what I meant to say. Just got ahead of myself. LOL but thank you for the correction

 

[mackmobile43]

Yeah sorry thats what I meant to say. Just got ahead of myself. LOL but thank you for the correction

On this mod is there anyway to eliminate the feedback when you turn the mic gain up fully?

 

[CBtalker205]

If I'm not mistaken you would have to use a resister with a lower resistence. That should take care of the feed back.

 

[Switch Kit]

Talkback is an interesting thing. And getting it right for given radio and tune can certainly be a variable. As well as what kind of microphone your using. Was the radio cap and resistored ? or not ? Does it have a good echo board in it ? or is it just tuned at 100% audio at wherever the power is set ?

There are many variables to conceder and what might work just right for you. Lets say I use a cap/resistored radio (low DK big swing ) that pretty much means audio is off the charts to begin with. Chances are , I would never run a Power mic on this kind of tune , usually NC or stock , for that I'd be right around a 50 to 68 ohm 1/4 watt resistor . ( I use 50s for my own stuff)

I like around a 82 ohm for a diode mod on a 148 (again , that's with stock or NC mic) NC mic's will always stand the cranked out audio on these types of talkbacks , stock mic's leave a little room for feedback ,

These types of tunes on these radios already have off the scale audio to begin with , chances are , if your feedbacking ? Your to loud to begin with or the resistor value is to low or you might even have a grounding problem . (Magmounts and Fiber Glass antenna's beware) could be even worse with a power mic.

for a light type talkback on these radios , I'd go between 70 to 100 with 82 being about the norm for me. But even then , it still can depend on given radio. All in all , what would cause the most problem with any of these radio tunes I mentioned would be a power mic. Just more audio on top of audio. (it's all over the place)

If you wanted to use one (power mic) with talkback , I'd guess to say anywhere between 100 and 150 ohm or so , it can be hit and miss. Now that of course is the cheap mans talkback . They have some pretty dandy variable talkbacks that can save a guy a lot of trouble.
(feedback) I can sorta dig the feature off an on off switch , but I like talkback , after a while of getting used to it , it kind of has a way of letting you know your OK and set where you want to be. Especially concerning echo boards and or noise toys and recorders (if your into that kind of thing?)

Talkback just isn't for everybody.