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Thoughts on LDMOS amplifiers?

Discussion in 'Amplifiers' started by TIN_CAN, Nov 8, 2019.

  1. TIN_CAN

    TIN_CAN Well-Known Member

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    Thinking on trying out an ebay LDMOS amplifier, for shits n giggles, anyone else have any experience with them?


     

  2. Shockwave

    Shockwave Sr. Member

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    As long as you're very careful to match the low drive requirements of these devices, you'll be pleased with the results. Most only require about 1 watt of drive and that usually means you'll need to add a 50 ohm attenuator to the input. Just turning the drive level down on the radio will not prevent dangerous excursions above that level.

    This is the main reason you do not see many completed amplifiers being sold at reasonable prices. They simply have no reliability if over driven without sophisticated electronic protection to guard against that possibility. Even the "indestructible" BLF288XR burns up instantly when driven a little too hard.
     
    Shadetree Mechanic likes this.
  3. Mudfoot

    Mudfoot Elmer

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    It looks like we'll be seeing more of these in the future.
     
  4. Pappas and Beer

    Pappas and Beer Stripper Licker, number 18

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    They seem to be giving the most watts per dollar. I would be interested to hear people's experiences.
     
  5. TIN_CAN

    TIN_CAN Well-Known Member

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    I still plan to buy one and test it out, thanks for all the input guys.
     
  6. nomadradio

    nomadradio Analog Retentive

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    LDMOS is the wave of the present.

    Bipolar is getting to be like tubes were in the mid-to-late 1980s when the last USA tube factories were shutting down.

    They won't ever go away completely, at least not for a decade or three. But they'll just fade away.

    Year by year.

    A little at a time the way RF tubes have been for the last 30 years.

    73
     

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