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    rf power meter for 433/458 Mhz

    david f
    AMS Treasurer

    Posts : 1996
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    Age : 68
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    rf power meter for 433/458 Mhz

    Post  david f on Sat Dec 30, 2017 11:29 am

    These notes refer back to the antenna experiments I was doing a year or so ago. (See the main thread on openLRS for the details.

    It turned out that the commercial/as supplied aerials actually work rather well and provide the best trade-off between performance and ease of use. Yagi aerials don't fit well  inside a submarine!

    An RF power meter was a useful tool to measure relative power. Tim S has given details for a commercial meter on the main openLRS thread but I looked around for a cheaper alternative. And here one is - Thank you eBay!

    The board is connected to a rubber ducky aerial and a 12v supply. I connected the output to a Digital Voltmeter on a 2v range. Very little soldering required.

    The unit puts out 0.5v which rises to 0.6 to 0.7 volts on a signal. It seems to work well/repeatedly and avoids having to wander around town looking at your transmitter!

    Some details:

    See description
    Order 100--2500MHz RF power meter logarithmic detection power detection HF UHF BoardView similar items
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    1 item sold by wishyou-happy
    100--2500MHz RF power meter logarithmic detection power detection HF UHF Board
    100--2500MHz RF power meter logarithmic detection power detection HF UHF Board
    ( 331792564238 )

       can measure 88-108,300,433,915,2400MHz , etc. Frequency
       Supply voltage: 6-15V

       Operating Current: 15mA

       Working Impedance: 50 ohms

       Input frequency: 100-2500MHz (Extended mode can be used 10-3500MHz)

       Input power: -70dBm ~ 0dBm (up to 70dB dynamic range)

       Output slope: 18mV / dB

      Current date/time is Wed Dec 19, 2018 11:12 am