Comtech ATV TX Modules Info

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

The module requires a negative bias to the GAasFet's 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 if use on GB3KM where the dc ground was shorted to RF ground via the Power supply connections and eventually the Driver GAasFet failed!

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

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200mW Module 6MHz Sound carrier boost