Here's why factory service manuals are useless.

Discussion in 'CB Radio Forum' started by rabbiporkchop, Dec 26, 2020.

  1. rabbiporkchop

    rabbiporkchop Road Train Member

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    8 transistors with different amounts of gain and a different curve between all of them is what caused the IMD. Dave did the best he could. Even though there's 4 pairs and each pair is adjustable, one adjustment for two transistors only works if those transistors have an identical curve. It's like blueprinting and balancing an engine.
     
  2. Ridgeline

    Ridgeline Road Train Member

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    Ok I get that but then think about this, if you are aligning the transmit section, the manual doesn’t assume there has been a replacement of the devices in the rf sections, it is about aligning the transmit section for a given performance.

    However it does assumes that the tech knows more than just be a parts replacer.
     
  3. rabbiporkchop

    rabbiporkchop Road Train Member

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    Which can't be achieved without replacing the finals with a matched set.
    Desired performance won't happen without tighter component tolerances to begin with.
     
  4. Ridgeline

    Ridgeline Road Train Member

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    So then you are assuming the radio is junk until someone replaces factory components to make it usable, which then begs the question, why by it in the first place?
     
  5. rabbiporkchop

    rabbiporkchop Road Train Member

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    After thousands of them, no assumptions are being made. They are all equally worthless.
    The reason for purchasing it is the satisfaction I get in knowing you can't make one perform like mine. Otherwise I would stick with a stock Cobra 148 or something type-accepted right out of the box with no alterations.
     
  6. Ridgeline

    Ridgeline Road Train Member

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    Rabbi, Happy New Year.

    You are assuming I want to get a radio that is a rice box that will sound like yours.

    I already have radios on the air that sound like yours maybe better, you could hear one on 3.885 and another on 40m. You can catch my browning and my citiphone on 19 every once in a while, they work rather well and loud.
     
  7. rabbiporkchop

    rabbiporkchop Road Train Member

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    Happy new year. No assumptions are being made.