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China made Cobra 148gtl clarifier problem.

American-Vulture

New Member
Feb 18, 2019
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I have a China cobra 148gtl that I want to unlock the clarifier but
the china radio now has a plug with 2 red wires and a black wire on it.
Any one know how to unlock it? I tried some other conversions but did not get any luck just a 10 kc drop.
Thanks,
 

The clarifier didn't work at all (must have not used right conversion) It acted like I installed a switch to
slide freq.I have 3 different cobra 148's and all different wiring,(colors also)
.just dropped all channels 10 kc's.so I returned it back to normal and yes I adjusted it and it is smack on freq.I don't want to spank the radio just want to get A channels in.
 
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20150512_002516.jpg 20150512_002552.jpg 20150512_000618.jpg I had this issue with one I did about 15 years ago. I really can't tell you exactly what I did to fix the issue because it was so long ago, but I THINK it has something to do with where I grabbed the 8V from. It might have been something with the diodes as well, but, again, it was a long time ago.

OK, I found some of the pictures I took when I was working on it. Maybe these will help.
The center wire to stays connected to the potentiometer and you grab power from the 8v regulator here.
You can also see that I jumped R174 and R175.
 
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View attachment 29477 View attachment 29478 View attachment 29479 I had this issue with one I did about 15 years ago. I really can't tell you exactly what I did to fix the issue because it was so long ago, but I THINK it has something to do with where I grabbed the 8V from. It might have been something with the diodes as well, but, again, it was a long time ago.

OK, I found some of the pictures I took when I was working on it. Maybe these will help.
The center wire to stays connected to the potentiometer and you grab power from the 8v regulator here.
You can also see that I jumped R174 and R175.
Looks like r144 is missing also.What about d52?So the black wire from the pot goes to ground?
and other goes to 8 volts?
 
Like I said, it's been a number of years since I did this and I really don't recall what I did. I just do this as a hobby and I haven't messed with one since.
I don't really remember all that I did. I do remember referencing the method for an older 148 though.
Here is another pic for reference20150512_000559.jpg .
 
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999 this is all the info I have for the mod.

This is what I have:
1 Cut R44
2 Cut D52
3 Solder a jumper wire across R 174 (or remove it and put a jumper in its place)
4 Remove red wire that comes from the Fine tune pot from the board and hook it to the + side of C84
5 Change R175 to a 1KOhm
 
What I can tell you is the radio had about 17kc worth of slide to it. It would do a full channel one way, and about 7kc the other.
 
maybe American vulture can use this info.

999 I bet you had the radio with the resister on the side of the board that powered the PLL. ever one I did with that setup would slide like you are talking about. some one else may be able to chime in with this mod. I like the older radios that would only slide 1kc each way. they had way less problems tuning in another radio to talk with.
 
maybe American vulture can use this info.

999 I bet you had the radio with the resister on the side of the board that powered the PLL. ever one I did with that setup would slide like you are talking about. some one else may be able to chime in with this mod. I like the older radios that would only slide 1kc each way. they had way less problems tuning in another radio to talk with.
Every 148 that I have done the claifier on has slid like that. Not sure if I'm doing something different or what, but I've never run cross one that was limited like that.
On a side note....a friend of mine had a 2000 with a crystal kit in it that would only slide 3kc either way. All I did was take out the crystal kit and jump the PLL (swapped in an 8719) and the slide opened right up. Full channel one way and 7 or 8kc the other.
 
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