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13cm 200mW Comtech info



    Cluster Activity

    Spots per uW band today:
    UK spotter or spotted only.

    Solar data:
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    Date:18/11/17 Time:17:41
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    UKHASnet
    13cm 200mW Comtech info

    Watch out with you DC Power connections to the 200mW module!

    The module requires a negative bias to the GAasFets in the final stages and this is done by using a virtual ground in the module.

    All of the module Ground is held ~1.4v above DC Ground using the two diodes situated next to the tx can

    This was only found by accident when in use on GB3KM where the dc ground was shorted to RF ground via the Power supply connections and eventually the Driver GAasFet failed!

    A separate ground isolated power supply is required for the TX module at all times!!


    200mW DC input

    200mW top



    200mW Module 6MHz Sound carrier boost:
    200mW Module Sound boost











    Last page added:16/08/17 15:45
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