Hi Richard, A quarter wave stub tuned to 2 meters will be 3/4 wave at 70 cm. Therefor it will reject 70 cm as well. Greetings from Copenhagen. 73 OZ1MY Ib ----- Original Message ----- From: richard@g3rwl.demon.co.uk To: amsat-bb@amsat.org Sent: Tuesday, August 14, 2007 10:32 AM Subject: [amsat-bb] Re: AMSAT-BB Digest, Vol 2, Issue 504
Scott
The other downside is that even with two transceivers, I'm unable to
work
full-duplex. The two bands on the antenna use seperate elements and feed points, but share a boom. Transmitting on 2m completely overloads the front-end of the IC-7000. While full duplex would be useful, it's not absolutely necessary.
Theres also the old fashioned stub, you put a 2m quarter-wave open-circuit
stub on the 70cm feeder close to the input of the preamp (maybe another close to the input of the rig). A little bit tricky to tune (fabricate it long and snip tiny bits of it off until you get maximum attenuation).
73 Richard G3RWL
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