Dead Radio, time for a new one

[Firebird]

Hey, I am a fairly new driver (1 1/2 years). I have been using a small chassis Midland radio that I had just lying around the house. After switching to a new truck a hooked it up backwards and popped the fuse. I put in a new fuse, but now it pops the fuses no matter what. I can't get it to hook up at all without popping the fuses. I tried another radio and it works fine so I think I screwed up my Midland. I might check into getting it fixed as it was doing great.

So, I have been looking around at some of the other radios. I like the Cobra 29's and know that everyone has them. I just don't like the green lights on the NW version.

What is the opinion of the Uniden PC-78 elite? I like the lights and the overall look of that radio and I see it is available in about any truck stop.

I really didn't want to spend more than about $130.00 on one.

Thanks,

Dave

[BobC]

If you didn't use a "trucker fuse"* in that radio, you probably didn't damage much.

There's a diode across the power leads in all radios that sacrifices itself by shorting out once the radio is reverse powered.

It's meant to blow the right sized fuse & survive a couple times.
That's "if" you didn't get crazy with the fuses.
Usually it's just this diode that pops.
About 30 cents worth of part & 15 mins of labor.
On other occassions, something else might pop as well.
You sometimes take out the audio amplifier IC.
Usually under 10 bucks for the part & a good half hour labor.


*Trucker fuse-The ones marked 3 amps but really fused for 20.

[Firebird]

Several years ago I studied electronics in college so I am pretty handy with a voltmeter. How would I check to see if that diode is what blew?

[BobC]

Originally Posted by Firebird

Several years ago I studied electronics in college so I am pretty handy with a voltmeter. How would I check to see if that diode is what blew?

First, trace the + power lead as it enters the chassis.
It will probably drop down into the pcb before routing to the on-off sw.

Somewhere near the + power lead entering the pcb, there's going to be a 1N4000 series diode with it's anode connected to the + power lead.

The cathode will be to ground.

Break or remove a lead off that diode & check the power cord for a short.
If the short is gone, reapply power to the unit & check that everything is working ok, especially the audio amp IC.

[MedicineMan]

I have a uniden Grant XL for sale. The best uniden ever built. Plus it hs echo/reverb, talkback, turner roadking mic, upper and lower channels and the grant is side band also. It's in the for sale section under cb's

[outlawwv]

Originally Posted by Firebird

Several years ago I studied electronics in college so I am pretty handy with a voltmeter. How would I check to see if that diode is what blew?

i'm sure that's what's blown -- i did it to a galaxy 88 once -- it was a quick cheap fix at the local cb shop

[randompower]

Originally Posted by MedicineMan

I have a uniden Grant XL for sale. The best uniden ever built. Plus it hs echo/reverb, talkback, turner roadking mic, upper and lower channels and the grant is side band also. It's in the for sale section under cb's

Is that the radio they call an (import)? if so I hear they are illegal.

[MUSTANG]

The Uniden Grant XL and LT are legal radios. I have the Grant LT and its a very good radio. The PC 78 Elite is a fine radio and with a proper Antenna and coax will do great job.Good luck

[capnhector]

my question to you is how much did you pay for your midland, if it was a budget 30-40 dollar cb do the work your self and if you totaly fry it get that nice uniden you want. my motto when something breaks its time to upgrade.

[MedicineMan]

Originally Posted by randompower

Is that the radio they call an (import)? if so I hear they are illegal.

Any radio you hear that gets out more than a half mile is illegal. when yo hear the one guy that you can barely make out what he is saying..... that is the stock 4 watt radio. you may as well not have a radio