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mattsowders1989
12-20-2016, 01:12 PM
I've assembled the "swing kits" with a pot for power level before for the cobra 29's but I want to put one on my 142 for AM. Not SSB. The radio has some sort of swing kit in it but I don't know where to look on the board to find it. I know it has one in it because it dead keys at 1.5 watts and swings to 5 watts. If anyone could help me locate this mod and give me some info on how to put in variable power, that would be very helpful. Thanks guys!!!


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222DBFL
12-20-2016, 03:33 PM
Well you could have the AM power tuned down and the modulation turned up as well and you could possibly see that kind of power as well Matt. Not saying the radio doesn't have a swing kit as it may very well have one. Check for a cap and resistor close to the final. There will be a cap on the top side and normally a resistor on the solder side of the board near the final. Hope this might help a little. Have a good one. And let me say it now. I am in no way a tech nor do I claim to be. Just throwing some possibilities out there as to what could be. Again, hope it might help. Good day.

mattsowders1989
01-07-2017, 07:29 PM
i need variable power. it was my mistake, it has no swing kit in it but i want to put variable power in it. i have the kit assembled but i cant figure out where to put it...

mattsowders1989
01-08-2017, 10:04 PM
Does anyone know where I need to install the variable mod at?


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222DBFL
01-09-2017, 06:46 AM
Back near the final. I believe it's JP36 on the cobra 29. Don't quote me on that though. Google has tons of info on it. Just google cobra 29 variable power mod. Here are a couple of pics and description of how and where it goes. http://uploads.tapatalk-cdn.com/20170109/cd6aafcc73e27f81e0be933891b30467.pnghttp://uploads.tapatalk-cdn.com/20170109/7107184d7612dc626a87249011f1ead7.png

The parts you have may not be the same, but the placement should be on the board. Hope this helps.

222DBFL
01-09-2017, 06:47 AM
Sorry this is for a cobra 29. Let me see if I can find one for the 142.

222DBFL
01-09-2017, 07:04 AM
Here is a simple pic of how someone did the variable power mod to 8719 board. Looks as if you cut the trace for VR6 which is the AM power pot. Here is the pic. http://uploads.tapatalk-cdn.com/20170109/562533d6ca3a381140060b7814c1fc2d.pnghttp://uploads.tapatalk-cdn.com/20170109/562533d6ca3a381140060b7814c1fc2d.png

222DBFL
01-09-2017, 07:06 AM
I would think you would just add the variable power mod where they are showing that you add a resistor. Add your variable power mod instead of a resistor in its place.

222DBFL
01-09-2017, 07:08 AM
Again, don't quote me on this. Hopefully someone else will answer as well. This was just with a quick google search. If your radio has the 8719 board, then search google for the mod for that board which is a very popular one. Again, sorry to mislead you with the cobra 29 mods and hope you get it all resolved!! Be careful whatever you do and good luck Matt.

mattsowders1989
01-09-2017, 10:14 AM
Thank you Sean. I wasn't able to locate anything on the 142. I did not search the board though so I greatly appreciate it. I've about got this radio doing some good broadcasting. It's direct injected. I am running about 75 watts going into a ameritron al-80 with the 500z tube in it. It's peaking out at about 1,000 watts. Dead key is about 200 and the swing goes between 900 and 1,050.


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mattsowders1989
01-09-2017, 10:15 AM
I have a cobra 29 in the car. I already put variable power on it. It's pretty simple.


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mattsowders1989
01-14-2017, 06:23 PM
im trying to figure out what coil to solder to though. i see the circut i need to break but i dont know about the coil

222DBFL
01-15-2017, 06:43 PM
Did you try the mod at VR6 Matt. Look at the last pic I posted. Shows a trace being broken at VR6 and then being placed there. You could add your variable power there couldn't you? Be like adding the resistor there but your variable instead. I could be wrong so look into this more before you dive in. Hope you find a way to add it. Be safe and have fun. That is what its all about!! And keep it clean and mean!!

mattsowders1989
01-17-2017, 09:17 PM
The mod does go at VR6 but a variable kit has 3 points. 1 and 2 will be in the break of your power VR. 3 will be tapped into the coil. I'm just not sure witch coil. I'm honestly surprised that no one has ever posted a how to for the cobra 142


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222DBFL
01-18-2017, 03:34 AM
Let me ask this. Do you see any coils on the board that resemble the ones one the cobra 29? I don't think it has those coils. I think you take the 3 wires, 2 terminate the break at VR6 and complete that circuit again. The black wire can then be soldered onto a tuning can. One of the metal ones. That is unless you have something different or more parts. But from what I have seen and searched for, which has been a little while, I can't find any other way to do it. Won't hurt to try. Do it without power and use a meter and make sure it works when you install the 2 wires, with the 3rd one soldered to a can. Might just work. Then power the radio up and see if it works okay. You may have resistors or other parts. Just add them as directed and take the black wire, which I am assuming you have, which I could be wrong, and take it to a tuning can and solder it.
Like I said, I did look for this mod and it's all I could find for your radio. The cobra radios do show a wire going to coils, L11 or L15 which is what the cobra 29 uses. Same for the uniden 68 and 78. Anyways. If no one answers the question for you, might want to give the way I found a try. Every dog has his day LOL[emoji106][emoji106][emoji6].
I hope you get it installed and working whether I am right or wrong, just want to see you get it done man. I know it's been done. Good luck and hopefully someone will get it to you!!!
73 and God Bless
222 Daytona Beach, FL
Sean

wookie
06-01-2019, 02:14 PM
never cut tracks looks bad and can cause problems and is not cosmetically reversible so why not just lift the leg of VR6 where the track to be cut goes neatness counts hope this helps.

mjd420nova
06-05-2019, 11:08 PM
Cut the trace, it is easily bridged with small wire and solder if needed. Done neatly it wouldn't even be seen, you don't need to gouge a canyon in the board.

wookie
06-08-2019, 05:16 PM
Why cut a track when you can just unsolder a leg of the potentiometer? much easier and neater of course thats just one mans opinion.