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I bought it for that purpose too. And the radio isn't that bad.. it does have to good points. Ok I've got the problem narrowed down. It's not the regulator. The voltage checks. But the final is getting full voltage. The bias trimmer is only getting .01- .03 maybe? Seems to low? I'm in the...

There was one I couldn't find. 18 something... There's on thing about cb I don't understand. I know that it produces a carrier and modulates inward tword 0. I use to not realize that. But what part makes it modulate? Is it the regulator? If it were my audio then none of it would work including pa?

This one has td2003 or ta2003 it's behind the transformer. I agree it's nothing special but I'm positive I won't get what I pay for it. With alil love it can probably perform good enough to drive an amp.. I learned my lesson with them. I seriously think all they did was turn the am power and...

I just got the radio today. On intent to widen bands and do some hi fi. I opened the radio immediately add the resistor for talk back and wired am power to the external... all its good so far side bands working better than I thought receive its ridiculously better than 29, to be at least. So I...

Today I should be getting my 148. This is my first radio I've owned other than a 29. I'm pretty electronically savy. Not pro but I am taking coarses. To my point. When I saw the Darlington configuration in place of the modulation transformer I had to have one immediately. All the things I...

This is not something in trying. It's more of a theory. A lil trick I use for lowering impedance in effect pedals and guitar amps is to use a unity gain, mosfet or jfet stages on the input. The mosfet has infinitely high input Z so it would not need any sort of coupling on the gate. Is this...

Yea, im willing to bet it's that relay. Before I understood why they use one on the preamp I put one in an amp I built. I found out when I turned off the amp and the receive faded. I was like ooooooooo. If you think about it, there's not really a such thing as a dumb question unless you don't...

I don't know that particular preamp but it's pretty typically a single transistor gain stage. Start on one end and work your way out. See if the relay works. It's there so that when you turn the amp off you won't transmit into the collector. After that I would test the collector for voltage. If...

I'm agreeing with you, I just built anoth err 2 pill and went through extensive learning to tune it properly and just wanted an opinion

But if I have a radio that has a higher output than what the amp need. Ex. Rfx75 into a 2 pill. Can I turn the variable down and make it work?

What exactly are these variables for? It looks like attenuate input. It's this if your dead key is to high?

Is it possible to remove this transistor? I'm rebuilding the input circuit, and I'm having great luck. Only problem is I think my Mic amp is causing tr17 to clip and causing feedback. I do believe it's mostly caused by the talk back but I do believe this it's happening. If I remove this...

Read up about adding diodes in a series with d8 on the cobra 29 to lower the carrier.. it's this better than the swing mod done with the cap and resistor? And also do the results end up with a splatter box like the rc mod?

I like the variable power mod. I can't get good results out of rc mod. Bleeds all over the place but u can do it

I've read up on receive mods for typical radios such as cobras etc.. i see that mostly all that takes place is a diode swap after the IF amp before the actual rf receive amp, and a transistor swap that is a bit higher of HFE. I dont have this transistor available to me at the moment and im...

That's a great idea man

Look on cbtricks main page under mosfet experiment notes.. it's not very clear but it's there on the left hand side of the page

Did you check it between mods or did you do it all at once? My guess off the top of my head would be the fet. Use your volt meter and check the screw head and the transistor tab for continuity. I think it should read about 500. If it beeps you got a problem. I'm guessing since you knew how to do...

This is a circuit I was mentioning on the previous thread but I added a couple ferrite beads and changed a couple values. I found the improved schematic on cbtricks of the cobra power Mic. (THIS IS NOT MY DESIGN. I JUST ADDED A LITTLE AND DESIGNED A LAYOUT/ETCHED OFF OF EAGLE CAD.) I solved my...

On one of the pics I included the output slug that I REMOVED a turn from and added a 68pf cap to ground. This radio is bleeding pretty bad and I'd love to fix this. Thanks