Sharing antennas

Osprey1163

Newbie
Premium Subscriber
Joined
Dec 13, 2017
Messages
26
I'm in the process of hooking up antennas in my new shack. I've got a TYT TH9800 Quad and an ICOM V8000 that need to be hooked up. For now, I've got a dipole hooked up to the TH9800 for 6 meter, but will be putting a 144/440mhz antenna on the roof this weekend. I ordered an MFJ-916b duplexer for the TH9800, but it hasn't arrived.
I'd also like to use the 144/440 antenna for the V8000 instead of putting up a separate antenna. Would it be safe to tap the line on the low frequency side of the duplexer to hook up the V8000 and share the antenna that way? I just worry about transmitting from one radio and harming the other through its antenna feed. If my plan won't work, what's the best way to do it? Thanks in advance for any advice.

Chris
kb3scn
 

chief21

Member
Premium Subscriber
Joined
Mar 2, 2004
Messages
1,336
Location
Summer - Western NC; Winter - Tampa Bay FL
Any direct connection between the two radios would be a bad idea. Your receive signal would be reduced by half and transmitting on one would almost certainly destroy the opposite radio. To be safe, use a coax switch and use one radio at a time.
 

Osprey1163

Newbie
Premium Subscriber
Joined
Dec 13, 2017
Messages
26
Any direct connection between the two radios would be bad. Your receive signal would be reduced by half and transmitting on one would almost certainly destroy the opposite radio. To be safe, use a coax switch and use one radio at a time.
Thanks for the quick response!
I knew the signal would suffer and suspected it'd be bad for the other radio but it never hurts to ask. The duplexer is on back-order so that'll give me a chance to get a coax switch. For the time being I'll plug and un-plug antennas as needed.

I've had my Tech license in 2008 but life got in the way and I wasn't able to do much with it after 2012. It's fun being back at it, but in a lot of ways I'm starting from scratch again. A lot of new technology has popped up too, adding to the learning curve!

Chris
kb3scn
 

tweiss3

Member
Premium Subscriber
Joined
Apr 24, 2020
Messages
104
Location
Ohio
Yes, the duplexer will allow you split off the 6m from the 2m/70cm and use the same coax, plus you have only one entrance to the house.

I used a comet CF-360B to split 6m from my 80m-10m HF antenna and use one coax into the house and it works wonderfully.
 
Top