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Re: Preamp bypass circuit


Yesterday I made following mesurements with the Preamp DC output voltage from my Icom IC-475 70 cm Rx/Tx:

-	The DC voltage drops to zero 15-20ms before TX RF is present at the antenna connector.
-	No matter what I tried, I was not able to transmit without this DC Votage dropped to zero in advandce
	of the RF.

So, I think, the  problem is solved for me. Take this preamp DC voltage, route it to a switch in the shack, so
I'm able to switch between U and S-Band. From the Switch route a cable to the mastmounted antenna switch relais.

Lets hope this scheme will protect my downconverter after installation.

greetings Paul HB9OMQ
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