[VHFcontesting] 1296 xvtr attenuator

Michael Sapp wa3tts at verizon.net
Tue Jan 19 12:43:09 PST 2010


>I'm trying to drive a 1296 Xvertr with my TS2000 but the lowest I can power 
>the rig is 5W. Does anyone have any insight?

Paul:  Try using the adustable attenuator in the w3ccx quick picks technical 
notes on the Pack Rats web site. It is essentially a 5W or larger 50 ohm 
load with a small value variable capacitor in series with a 10db 50 ohm 
attenuator for the QRPP output. You have to relay switch around the 
attenuator on receive or find some way to wedge the attenuator directly into 
the IF transmit port of the transverter.  I have seen a few microwave module 
xvtrs modified over the years with a 5 to 25 W 50 ohm termination bolted 
directly to the chasis next to the tx input port connector and a tap off 
from it via a cap and small matching attenuator going to the IF tx input. 
You may also need to build up a small milliwatt level diode detector  (or 
use another RF power measuring device) to make sure you are safely in the 
power range needed for driving the transverter.

Mike wa3tts 



More information about the VHFcontesting mailing list