Duplexer / Diplexer Selection, etc. ?

[BOBRR]

Hi,

Would appreciate any thoughts or opinions on the following, prior
to going out to purchase a Comet Duplexer unit.
Not that sharp with this "stuff" anymore at my age now, but
enjoy the sw monitoring hobby very much.

I do receiving only; no transmission.

Have a Airspy HF Discovery++
For reasons I'll never understand, it has only a single ant. input for the HF and VHF ranges.
Sure does complicate life. I have a convoluted switch "farm" now that I would like to simplify.

Was thinking about a Comet CF 360.

The fact that it is called a Duplexer rather than a Duplexer bother me.
Can it work "either way" ?

I would be running my long wire, for HF into one of the two freq spigots, and a Discone (or possibly my Scantenna ST-2) into the other

Then using what they show as an "input" as the output to the Airspy.

Do I have this correct ?
Thoughts and comments would be most appreciated.

Any other Comet, or other brand units that I should consider rather than the CF 360 ?
Am most interested in all <30 MHz and the vhf aero. and Maritime ranges. (perhaps 100 Mhz or so, and up

BTW: any cheaper units that would work, in your opinions, "as well" ? The Comet unit is a bit pricey.

Thanks; appreciate the help,
Bob

 

[AK9R]

Whether it's called "duplexer" or "diplexer", your intended purpose is the same: split or combine two antennas with one radio. Yes, these devices generally work both ways. If your intent is to connect both your long wire and your discone to your Airspy, then you want a duplexer/diplexer that has one high port for VHF/UHF and one low port for HF and one common port. The CF-360A ports are rated for:
Low Pass: 1.3-30 MHz, short whip with PL-259
High Pass: 49-470 MHz, short whip with PL-259
Common: SO-239 on body of device

In your application, you may want to consider the CF-360B which is identical to the CF-360A except:
Low Pass: 1.3-30 MHz, SO-239 on body of device
High Pass: 49-470 MHz, SO-239 on body of device
Common: short whip with PL-259

This is from Comet's website: Duplexers | Comet Antenna

I have heard people say that "duplexer" refers to a device that allows a station to transmit and receive simultaneously in the same band while a "diplexer" splits one port into two or combines two ports into one.

 

[BOBRR]

Hi,

Thanks,
Bob