cobra 29 problems

[KC2OST]

how do i find which ones to unsolder from the bottom?

I hold the radio up to a light with the parts facing me and
run my finger on the back of the board until I see what I want.

Then flip the radio over with your finger still on it to see
where to unsolder.

You need an unsoldering iron. They have them at RadioShack.

 

[lords]

how do i find which ones to unsolder from the bottom?

I hold the radio up to a light with the parts facing me and
run my finger on the back of the board until I see what I want.

Then flip the radio over with your finger still on it to see
where to unsolder.

You need an unsoldering iron. They have them at RadioShack.

I think your better choice would be Desoldering Braid
radio Shack Cat No.64-2090
works like a charm
Good luck

 

[minitrucker]

how does it work ? does the solder stick to it?

 

[lords]

Yes the solder sticks to it, and very well.
jut place it over what you want unsoldered.

 

[Switch Kit]

I got my James Bond 007 solder strips I keep in my wallet , You just got to love MacGiver 8) Oh .......and I never leave home without my trusty Tinker .

 

[Captain Kilowatt]

how do i find which ones to unsolder from the bottom?

You can hold the board up to a light as said before but I find a laser pointer is great for that.I just place the head of the pointer on the component lead I want to unsolder and look at the underside of the board. The laser dot shows up great.

 

[Captain Kilowatt]

I got my James Bond 007 solder strips I keep in my wallet , You just got to love MacGiver 8) Oh .......and I never leave home without my trusty Tinker .

Gotta love the Swiss army knife. I have carried a pocket knife,usually a Buck knife, since I was a youngen.One day I found a Swiss army knife on on the beach.It had never even been sharpened by the owner and looked brand new.It must have been lost only a short time earlier. That's all I'll carry from now on.I do have a little bit of McGiver in me. Ask the people I work with.

 

[DTB Radio]

how do i find which ones to unsolder from the bottom?

You can hold the board up to a light as said before but I find a laser pointer is great for that.I just place the head of the pointer on the component lead I want to unsolder and look at the underside of the board. The laser dot shows up great.

THAT is a great idea. I'd never even considered using a laser pointer for that, but that's almost the perfect method. It would shine through even some of the thickest boards.

 

[minitrucker]

how do i find which ones to unsolder from the bottom?

I hold the radio up to a light with the parts facing me and
run my finger on the back of the board until I see what I want.

Then flip the radio over with your finger still on it to see
where to unsolder.

You need an unsoldering iron. They have them at RadioShack.

I think your better choice would be Desoldering Braid
radio Shack Cat No.64-2090
works like a charm
Good luck

the prob is there isnt radio shack's here anymore

 

[mopar2ya]

If you have any old coax laying around, the braid from that will work just fine. It is too big IMO for radio work in general, but you are just looking for something to desolder one component.

If you don't have that, you can get by without desoldering at all. Just use a pliers and gently pull on the part while applying heat from the other side. Be careful not to leave the iron there too long or you will lift the trace from the board. Then, the hole will probably be too small to get the new part through. If this is the case, reverse the procedure. Heat the board and push the new part through. Once it is in place, add a little solder and you will be done.

You can even use your iron to desolder. If you clean the iron then touch the board, then repeat, you will remove a small amount of solder each time.

Mopar

 

[AA1QD]

Maybe. It depends on the extent of the damage. Sometimes all that gets smoked is the reverse polarity diode. If that is the case it is an easy fix. You can check it out if you are brave. All you will have to do is cut the diode shown in the picture below and power up the radio and see if it works.

If you have an ohm meter, after you cut the diode, check for continuity from the negative lead to the positive lead at the power plug. If a simple diode test shows short or very low resistance, don't power up the radio. Take it to a shop. If it shows high resistance, continue.

Please, use a fused power wire. A 3 amp fuse is plenty. You may blow that fuse if you try and transmit with it if it is modified, but 3 amps will help prevent further damage.

Please, if you do this, don't accidentally hook it up backwards testing it or you will have some serious repairs if you don't already.

If you find that this is the only problem, acquire a 1n4003 or similar diode from radio shack and replace the one that is destroyed with it. If you only cut the existing one, and never replace it, you will have eliminated the reverse polarity protection and the next time it happens the damage will be greater.

One other thing. I like to replace the diode with one that will provide more protection. A 6 amp diode will protect the radio and all that will happen will be a blown fuse if the fuse is less than 6 amps. Much easier to fix. I install the new bigger diode right on the power plug like Galaxy and the exports do.

Good luck,

Mopar

"I install the new bigger diode right on the power plug like Galaxy and the exports do.
"
what do you use for a diode there?