Birderman wrote:

HI,

I have a yupi MVT7100 which I connected a attic based Discone. The Discone
is a radio shack 25-1300Mhz model a few years old. I find this setup quite
acceptable especially for Airband monitoring, however, I wish to use the
shortwave reception of the Yupi, for this I intend to use a long wire
antenna mounted outside. To do this can I just join the two antenna feeds
together and connect or do I need a diplexer ?

If a diplexer is required has anybody got a URL where I can download a
circuit diagram of one for homebrew....

I have an ATU which has inputs for 50ohm coax, Longwire and balanced pair,
could this be used as a Diplexer as well ? or will it only function with a
single antenna connected ?

I look forward to any help on this issue
regards
Birderman


I have an MVT-7100. It's pretty good at what it does, but I think you'll find it'll overload if you put much of an antenna on it for HF.

If I was going to use an antenna larger than a few feet, I'd be inclined to configure it as a tuned loop.