Cobra 148gtl parts list

[kaos513]

thanks guys for all your help.

 

[Onelasttime]

Both the TRC-448 and the TRC-458 radios I've worked on use the 33uf value cap on their boards. Doesn't seem to be used much anymore for whatever reasons.

Why your 148 should have it in there is probably due to the fact that someone needed to replace a value and just simply used the closest value they had that would still do the job. It is too much if a 20uf cap was needed, and too little if a 47uf cap was called for. Would it work just the same? Probably; but I would use the value that was required by the engineers as designed. However, there are places on the 148 board that can and do need different values than what the engineers called for.

I would not worry too much about it. I opened up my President Lincoln to see what caps where in it to order new ones. It sat from about 2001 or 2002 until about a year or two ago. If you look at kits for the HR2510 and President Lincoln the cap values do not match. I looked in a service manual and at least 1/2 of the caps are double in value to what is listed in the Service Manual. The voltages are also higher. They are odd ball values and more important than that lead spacing and diameters are all off from what is normal today. Some of the values are so low at a given voltage that you can not even find capacitance rating that low in those voltages today. I am the orignal owner of the radio so I know it has not been touched.

Then I looked at Cobra 29, 148GTL and Uniden Grant XL and XLT and it is all over the place. I think that OEM's play fast and lose with cap values at the OEM level based on cost. On top of that every-time you have a board change or revision all bets are off. On top of that I have heard from many technicians and most radio's and circuits are not as picky as you would expect according to them. Keep in mind we are talking exports and CB radio's. From what I have been told the oscillator circuits are the only sensitive circuits the rest are pretty flexible.