Fried CB????

[Armz]

Im thinking Ive fried my AM cb,

Its a GME TX839N, It was working fine a few hours ago when il pulled it outa the Suzuki to chuck into the Terrano for this comming weekend. Me not wanting to spend lots of time wiring it in, I thought I could just run wires directly from the battery though the fire wall and into the unit, peice of cake done in 5 mins. I have a simailar set up already on the Suzuki except it also runs though a fuse on the way....

Initally I hooked the wires up the wrong way round and now the cb dont work, ie the screen is blank n seems no power is geting to it, tryed putin it back in the suzuki and now it dont work in there either,

I think ive fried it or something, Im assuming tis is possible??

If i start unscrewing the screws on the unit n get inside will I find anything of use?
Or have I stufed it?

If so sweet, hurry up every1 else move to PRS and it wont be a problem

[Jerry]

is there a fuse on the back of it or in it?

[curious_george]

haha yeah you will have fried something critical inside

Open it up - you've got nothing to loose if it's toast already. Look for anything burnt, or any burnt smell. Unfortunately, with electronics, if you let the blue smoke out, it's very hard to put it back in.

It'll most likely be a very small transistor that will have let go. If you can identify it, you might have a chance of getting a replacement from DSE or Jaycar.

Otherwise, it might be time to upgrade

[kiwipete]

IMHO it is possible that there is a surface mounted fuse on the inside, just maybe though. Open it up and have a look.
It is not necessarily a transistor that has fried, It could be any one of a number of components. The more modern equipment have IC regulators and voltage sensors etc, so as I said its just a case of look see.
Reverse polarity is so damed easy to prevent too with a simple 2c diode. I don't understand why manufacturers don't include this feature. Well I do actually, it's so us dumasses, (yes I've done it too), what reverse polarity our equipment have to go and buy another one.
Always use a fuse, but more importantly, double check the polarity first as a fuse wont always protect you either.

[Kiwimidi]

i suspect this unit will have a diode protecting from reverse voltage. the diode is accross the positive and negative wires (efectivley). what this diode does is only let power thru one way so when the power is round the right way the the power does not go thru. when the power is reversed it gose straight thru this diode as a dead short drawing heaps of current and blowing the fuse (that you did'nt put in)

what will have happned is it will have blowen either the power or ground track on the board before the crowbar diode. if its the ground track you can sometimes just ground to the chassie of the unit.

either way its worth looking at it. with car stereos (my daily job) there is about a 50% success rate with reversed units. what normally kills them is that guys keep putting in bigger and bigger fuses till lots of smoke comes out.

[Armz]

I pulled the unit apart, couldnt see anything that lukd burnt or blown on the board,

I noticed that when I put it in the suzuki its blows the fuse stright away.

As i no nothing about the eletronics and Im not really interested in pouring money into taking it to a professional seen its a dieing breed ive decided its game over for the AM. As ive got close to grand already tied up in 2 in truck PRS units and a handheld.

If anyone wants a 3meter AM cable with bullbar bracket, its only 2 months old and been used once as the old cable had a argument with the radiator fan give me a PM - make me an offer it costed me almost $50 bucks.

Chur