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MRF455 daughterboard


If you still haven't got it by the end of the year I'll just cut one :)
I have the art and code but the machine is tied up for about the next ....
I sent the order in, board house normally takes 3 weeks round trip
 
Keep in mind the picture of the board shown here was designed to replace the MRF477 transistor in HR-2510 style radios. The MRF477 has a pinout of Base, Emitter, Collector rather than the standard Base, Collector, Emitter found with all other finals used in CB's. Using the layout on this board to replace transistors other than the MRF477 will not work.

I just noticed the transistor you show is an HG MRF454. I'm real curious as to how the inside of this transistor looks compared to their 2SC2879... If anyone blows one up, be sure and post the guts please.
 
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Keep in mind the picture of the board shown here was designed to replace the MRF477 transistor in HR-2510 style radios. The MRF477 has a pinout of Base, Emitter, Collector rather than the standard Base, Collector, Emitter found with all other finals used in CB's. Using the layout on this board to replace transistors other than the MRF477 will not work.

I just noticed the transistor you show is an HG MRF454. I'm real curious as to how the inside of this transistor looks compared to their 2SC2879... If anyone blows one up, be sure and post the guts please.
I got a few 2510’s with bad finals and I’m using my Lincoln for reference. A few of the amp builders are repairing HG amps , sounds like something they’d make a video of the insides of one
 
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2912C201-6BA6-4A63-9D92-AF18D42DCBE2.jpeg Received the PCBs from board place , looks like I need to adjust a few things , guess that’s why the first order is never the final order lol. Board is too long to clear the lid but the MRF heatsink fits like a glove . Making the fingers a little wider also.
 
At a watt or less input drive the 1446 looks to have more gain then a 455 or a 454
MRF gain.png
 
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  • @ heartbreaker3473:
    Hello gentlemen and Ladies. I have the dreaded RCI-2990 receive issue where my radio gets distorted when people get close to my location. I found the C90 Capacitor, but I can not for the life of me find the C89 capacitor. Can or does anyone have a picture of the exact location of C89 ? Thank you in advance, Wes
  • @ AudioShockwav:
    Wes, it's better if you start a thread on the main forum, more people are going to see your question.
  • @ heartbreaker3473:
    Okay, sorry, will put in a forum
  • @ heartbreaker3473:
    I put it in the general disscution help area and started a new thread. Thank you for letting me know.