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My old friend President Jackson.

Here is the section of the Jackson schematic that has the AGC parts for replacement.

C31 is an electrolytic cap that will need to be removed.

The resistors R41, R43, and R47 will need to be changed out with different values:

Remove C31 (.47uf )
Change R43 (10K) to 1k
Change R41 (150K) to 270K
Change R47 (1.5K) to 3.9k
Click to expand...

Jackson_zpsf6082755.png


Gave it a quick but much needed freq alignment.
About to do the AGC mod next.
Works fine so far . . . Except for receive overload . . .


Top Picture: Just fired it up!
Bottom Picture: Shows the location of one electrolytic cap with a black mark on the top of it (I put the black mark on it to make it visible to all y'all) in the center of that photo. That is C31 - to be removed. The resistors that need to be upgraded are found to the left, right, and in front of that cap. You will find this location in the center of the radio just slightly twards the back. Easy Peasy...But NOT responsible if you do it wrong...
 

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I won't be able to map the bands tomorrow. Got my homebrewed counter out today. It ain't a working, have to see if I can get it straightened out.

Thanks for the AGC mod info.
 
I'm interested as well. This could fill my want for a 10 meter SSB unit and still give me the ability to "listen" in on CB.
 
Robb said:
You right . . .

Trouble . . . trouble . . . trouble . . .

First, the receive does overload on SSB with strong local signals.
Badly.
Second, it is waaaaay off freq right out of the box (about ~300hz/more!).
Just for starters.

I am working on a local's hacked-up 148GTL and will finish up with it in a few hours.
Nice old radio needs a bunch of TLC.
Putting it back to stock and removing the hacks one by one.

When I get done with it, I will open up the Jacko and see if the AGC circuit has the original spec'd parts in it. I'm guessing that it does. While I was out buying some parts for this 148, I picked up the three resistors to modify the Jacko's AGC circuit. This involves taking out one disc cap and changing the values of three resistors. Not an expensive mod, as all three resistors cost me less than a single dime. But it will take time to straighten this radio out.

The radio I got just might even be defective from the factory; dunno yet . . .
Click to expand...


It sounds like the shop in Ohio is a place to avoid if they ship radios out of alignment.
 
looks like ill be picking up some resistors tomorrow, i have been just talking dx with it and havent really noticed any ssb distortion, but i dont think i have had anyone peggin out the meter yet, mod looks easy enough, might as well do it
 
what about the fine clarifier unlock mod,, this one is listed for an original jackson:

1. Remove D58
2. remove brown wire at fine tune (where it connects to pcb)
3. re-connect brown wire from step 2 to cathode D69, Realign

???
 
I was just wondering what their response will be when users call and complain about the AGC defect.

I was thinking maybe they were not offering a warranty.
 
I get that it's a brand new radio with warranty and all, but did you take a peek under that bias diode and see what final it has?
 

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