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i have a issue with my cobra 139 23 channel

The C1096's are part of the RX audio circuit. The finals will be located near the front of the radio on the far left side of the board. They should be labelled C1306 and C1307. Replace the one that's labelled C1307. If you don't have a C1307handy to replace it with, you can either put a MOSFET in, or you can purchase Eleflow 20W final from Weazle66 on Ebay. Those are direct replacement for the C1307's and C1969's and they work well. Good luck!



~Cheers~
 


Actually, Double R's radio is a 23 channel 139 that has the 40 channel crystal selector put in. It's not a D858 SSB chassis. It's a completely different board that can't be modified for a MOSFET final in the same manner as a D858 chassis. It can be done, tho.

The parts you will need will be an IRF 520N from International Rectifier, an EKL companion part EN-369FN, and a 56k ohm 1/2 watt resistor. The resistor you can probably get at Radio Shack, but the MOSFET and the EKL part you'll have to get off the internet. You can find MOSFETS supercheap off Ebay, and you can get the EKL parts from places like Copper Electronics, and I believe H & Y Electronics.

Let me know if/when you get all the parts needed, I can try to walk you thru the process. If you are the slightest bit uncomfortable with trying the conversion, take it to a reputable tech and have it fixed. Don't mess up your radio! :unsure:

~Cheers~
 
312619_10150414384996154_505121153_10586583_1059056333_n.jpg
311474_10150414383501154_505121153_10586578_515669018_n.jpg

The 40 channel conversion the top pic and the board is on the bottom
 
Actually, Double R's radio is a 23 channel 139 that has the 40 channel crystal selector put in. It's not a D858 SSB chassis. It's a completely different board that can't be modified for a MOSFET final in the same manner as a D858 chassis. It can be done, tho.

The parts you will need will be an IRF 520N from International Rectifier, an EKL companion part EN-369FN, and a 56k ohm 1/2 watt resistor. The resistor you can probably get at Radio Shack, but the MOSFET and the EKL part you'll have to get off the internet. You can find MOSFETS supercheap off Ebay, and you can get the EKL parts from places like Copper Electronics, and I believe H & Y Electronics.

Let me know if/when you get all the parts needed, I can try to walk you thru the process. If you are the slightest bit uncomfortable with trying the conversion, take it to a reputable tech and have it fixed. Don't mess up your radio! :unsure:

~Cheers~

thought it was an 858 chassis thanks for pointing that out(y)
 
Wavrider ~ No Problem mate! Just lettin' you know. :D I used to have one of these 139's converted like Double R's radio. The radio was wonderful. Only reason I don't have it now is because it took a nasty lightning hit, the radio caught on fire.

I have a Midland 13-893 that has the same 23 ch. board in it, but mine has a 10 position rotary switch on the side that runs the extra frequencies, on ch. 1-4. I prefer the conversions tho like Double R's radio with the 40 channel dial. My Midland DOES have the MOSFET final mod done to it, and it works great.

Just let me know if/when you get all the parts.

~Cheers~
 

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