The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

Ive got a question about power mics and echo mics. I just got a superstar dm-452 and ive tried it on a couple of my old cobras and all it does is squel. I turned the pots in the mic down to the point where the radios have no swing then the squel goes away. But the radio sound like %#$%.
I have the dynamic turned down almost all the way, turned the modulation pot (vr-4 in my 29 ) down all the way and it still squels. The s-meter pegs and the radio also has audible whines inside the case. Do these mics just overdrive the radios. I also got and old newtron power mic that ive tried to run on some old midlands ive got and they do the same thing. Is there something im missing or do all powermics sound like crap.

If adjusted properly they should work ok, keep in mind that the problem may be the talkback adjustment in the mic.

Ive seen that sometimes the squeel is from rf feedback. I do not have talkback on either radio. I tried the defpom resolution for feedback under radio mods. Which was a 1k resistor and two caps. Still does the same thing. Is there something else i can try for rf feedback or could it be something else causing it. Its only the new superstar mic that squeels. All of my other mics work great I just wanted to add echo. Thanks, Mike

The Super Star microphones are great and I have used them for years, hard to find now, but they are made by Aries these days. The mics are naturally "hot" and the simple trick is to adjust the microphone the way you want it and then back off the mic gain on the radio until it stops squealing, this is common and turning your mic gain back is not going to cause you to sound any less loud, this is a myth and some guys just can not get over the facts, but, when you have 2 audio amplifiers inline, someone has to give to get, you have to "balance" all that extra audio amplification.

BUMP-BUMP !
Dodgem

Have you checked to see if the mod limiter is intact, many times these are removed or "hacked" by less than skilled techs. You may simply be overdriving it without the limiter in place. Let us know what you find!

yes i got same mic.and i agree gotta turn down mic gain on radio.mines set
at 50%much higher and mine squeals.i got the audio inside mike all the way up
you probaly turn your vr for modulation all the way up also.just use your mic gain

Qucik question my cb radio sqeals when I key up, but if I hook a jumper wire from the spring of the D104 and touch the other end to the mike plug that pluugs into the radio it gone and if I take it away it comes back. What could that be, it just started out of the blue.


Ken


kpeppenelli@cfl.rr.com

From where did u buy The Super Star microphones? Which brand?

Let me answer my own question, there was a bad ground that I fixed, thank you Ken your Welcome

Bye


Balludoctor