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MIDLAND CB MODEL 79-265 MOBILE EXTRA CHANNELS/CLARIFER MODS

Discussion in 'CB Radio Modifications' started by Retro CB Guy, Dec 26, 2014.

  1. Retro CB Guy

    Retro CB Guy Active Member

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    Hi I'm interested extremely in finding a proven way to get some upper channels above 40 on this radio so ANYBODY ?



    Clarifier opened too, confirmed method on that as well and these extra channels as one person I heard knows it's possible but has not gotten back to for whatever reason...

    Whoever helps me too I can get you the service manual to this radio as I've latched onto that so that should help as well, but someone out is bound to of have the channels installed and it works but I need the goods on how it's done please in detail...

    Thanks in advance 73's - Retro (Jim) 79-265_sml.jpg 79-265_MOBILE_1.JPG
     

  2. Robb

    Robb Yup

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    What PLL is in it?
    Chassis looks like a Cobra 146GTL as far as I can see . . .
     
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  3. HomerBB

    HomerBB Sr. Member

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    PLL - LC7131
     
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  4. Retro CB Guy

    Retro CB Guy Active Member

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    Yep ! Midland 79-265 use the LC7131 PLL chip in a single crystal (10.240 MHz) circuit...
     
  5. Robb

    Robb Yup

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  6. ExitThirteen

    ExitThirteen Grumpy and Cranky

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    It can be modded. I don't have time to dig thru my notes, for specifics, but it mods the same way as you would modify a D2824 chassis with the chipswitch mod.

    (From the top of my head)

    On this radio, you don't do a chipswitch, however. Ground pin 20, isolate pin 9 (if needed, can't remember if pin 9 is grounded or isolated), and put a switch between pin 9 and ground. This will give 27.420-27.860. You then have to unlock the clarifier, and install either a super slide diode, or a 5.6uh choke inline with the existing varicap diode to get the clarifier to slide the 5 khz back so you can hit 27.415-27.855.

    ~Cheers~
     
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  7. Retro CB Guy

    Retro CB Guy Active Member

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    Hey bro, Can you please reply to me on how to do this mod I'd be happy to give you my phone number or email, but I started a conversation with you also trying to obtain the info, does one need an expo kit in order to do it and which one if need be, but I wanting to know how you accomplished it please if you'd be so kind to reply to me Exit13 sir ....

    Retro 73's cheers !
     
  8. Retro CB Guy

    Retro CB Guy Active Member

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    Sorry I see you replied and that that was an older post ooops.... But didn't know if I need an expot or some kind of expander kit though so not a total loss on this post lol...
     
  9. tecnicoloco

    tecnicoloco Tweaknician in Training

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    Contact Gerhard for your radio expansion modifications

    He can design and build a solution for you for a price

    http://funkservice.at/cb-radio.htm

    http://funkservice.at/en_pll-modul.htm
     
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  10. Retro CB Guy

    Retro CB Guy Active Member

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    Thanks bro, I like any option that works well. I think Exit13 is onto something though and I'll check that out first...

    73's
     
  11. Tucker442

    Tucker442 101E

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    Does anyone have a schmatic for this radio? I have one that some wonderful person removed 2 transistors, a diode and resistor in the audio circuit so on SSB it sounds like crap but AM screams. I'm an SSB guy never use AM so this radio is useless to me. I would love to get the part numbers to fix it. Thanks
     
  12. AL567

    AL567 Well-Known Member

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    I used to have that radio years ago. Bought it brand new in 1991. Midland added a heat sink to the rear of the unit. It was a rather large radio best I can remember. I sold it a few years later. Seeing it here makes me wish I had kept it.
     
  13. Roosta

    Roosta New Member

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    Can anyone tell me how to check my swr's on this radio..? I know that I need to calibrate first but not sure where to set the calibration on the LED's....
     
  14. Ay589

    Ay589 Hammerjockey Radios

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    Old and possibly non related. But I have a realistic walkie, it has the lc7131 pll, I pulled pin 20 out of the board and soldered wires in place and to the pin to a switch. Open its low band and closed its regular. Not sure if this works with your radio but that's my .02 on mine with that pll that's "unmodifiable"
     
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  15. ButtFuzz

    ButtFuzz Anti-BS Advocate ● WO0WOO ● Reverend Doctor

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    If one pulls out and replaces one of the frequency mixing/making loops, ANYTHING can be modified with enough time and money. For all practical truck stop hack shop purposes, the LC7121 (Sanyo) PLL is unmodifiable. Can ExitThirteen do it? Yep! ('cause he is the man!)

    My question is why would someone bother?
     
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