Ahh, here's the rub I have, I know the board, it parts and layout - and know by sight what to look for.
But when I tell someone this info, based upon the "road map" my mind uses, I see there are the visual cues that many do NOT see like I do...
So what is one to do - or say, or even explain? To me, presenting the schematic, of the part - or photo of the area, even though it's labeled L22 and R56, the part in the photo also represents this same configuration but due to upgrades and technical add-ons and accessories the parts count is now off by several magnitudes..
The Silkscreen is what many a tech needs to go by, I understand that.
I do apologize, but only on my behalf. I cannot apologize for others and their engineering. I somehow manage all this stuff in my head because, I was left to do this, by myself all day, for several decades and the rest of you suffer from it... Long ago I learned - due to the nature of the Cobra Uniden and Realistic boards all having silk-screening of same alphanumeric, the issue becomes amplified when the boards of the same MODEL of radio - add more to the boards than they can keep current in their own schematically-documented archives.
These same chassis have been upgraded and added unto themselves and still are what they are - makes the mess - messy-er, on top of the fact that many of the same Model use just a different Suffix - making the Messy- er - the messiest of any radio brand.
How can I answer?
By writing the following?
- "When you look at this photo (schematic or Graphical Layout) The thing-ah-mah-jiggy with that doo-dad that's has a whatchamacall-it on it? Yeah, That's the one! That keeps the RF on the board and it has to go thru (you know) those things with the stripes then it went thru that bolted thingnamabob that has the square black face with all those little numbers on it - some of it that says 2078 some even use IRF520. Then you need to remember that those whirly-gigs of curly-Q's of wire afterwards, on that brown straw-form with the slot for the wax coated black stud ? Yes, there by the corner- is where all that goes to...
Chirp - Chirp - Chirp...
Ok, this is why I post so many images - seem to repeat over itself, not because of I like doing this, but because it has to be shown what I can relate to while you work on the board you have. We are using this forum to give others a chance to look ahead and realize that even though it's a Cobra 25 or a Cobra 29 or even a Uniden 78 and it's Cousin the PC-66/68 - none of their ROOT manufacturers stayed with the same radio outside - but inside, they did - they simply upgraded - added a number and then suffixed to that to show, Hey! We have a new line (of the same old thing) - new parts just flashy, under same old wrapper..
They put these parts inside - and we're supposed to fix it when it goes bad...
That's is where Documentation fails - the above posts are EXAMPLES of work for others, it's me helping others to accomplish that same feat you're trying to do.
They were successful - we tried to preserve the VALUES and ASPECTS of part orientation - not the exact part numbering- only it's changes to the OEM values to archive the help - just what was done to leave a trail of bread crumbs for others to follow.
Sigh- the boards photos and graphical blandishment posted in #31 above were for a Cobra 19 - but the MOSFET values of the EKL subs' were of the most importance, we then changed several other parts along the audio path of the chassis - so it should have sent up a big flag to let you know the BOARD, and the values of the region in which these were affected these specific spots Are Different and can help you decipher, but if you try to follow too close you can respond like what you just did...so what you see above, is a "Cliff Notes" version of Shakespeare - not the Poet - The Rework of another chassis that uses a similar concept of your thinking of EKL, Limiter and Audio Mode and they make it work by do this...TAH DAH!
Well, this time, it didn't work.
Here's a link to help you find ways to utilize the MOSFET values used and their part numbers...
President Bill Service Manual | WorldwideDX Radio Forum
In the above thread are posted schematics of the radios that use MOSFET's and are current - the snips provide the user with the METHOD and VALUES of the parts of the Driver and Final as they are configured in that particular radio.
So the MOSFET design, since the CB Tricks days, has changed in how they approach the methodology to make the MOSFET work - some are simple like the EKL, you just have to pay close attention to the values. While others use the EKL but are also supplanted with a bias trickle voltage from the 8 volt TX feed.
Well, my week is shot...
I guess I'll hide in the bushes for a while...
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