Any9ne know if this antenna mod would work? 40/20m dipole

[W5BRM]

I have a 40m hamstick dipole using a MFJ-347 as the center support. I'm wondering if it's feasible to hang a 20m inverted V using the hamstick mounts while the hamsticks are still mounted to it, making it a 20/40m dipole. I currently have the 40m hung as a vertical. I am wondering if keeping it as a vertical would affect the 20m inverted v in any way? How/will would they interact with each other in a negative way?

I have a bunch of 16g coated wire and I just need to solder a couple ring terminators to the ends and attach those to the screw in points on the hamsticks and raise it back up. OR I could just remove the hamstick dipoles and make it a monoband. Just need to get a few 3/8 x 24inch bolts.

Anyone have any advice on this?

Thanks

n2nkw

[NQ6U]

I can't see why it would be any different than any other fan dipole but, before you transmit, I'd put an antenna analyzer on it before you transmit just to be sure that your SWR is in the ballpark. PA transistors don't come cheap.

[K7SGJ]

I can't see why it would be any different than any other fan dipole but, before you transmit, I'd put an antenna analyzer on it before you transmit just to be sure that your SWR is in the ballpark. PA transistors don't come cheap.

PA transistors are a lot like buses, they don't come, they arrive.

[W5BRM]

Not a problem there. Got a mfj259c i use to tune the hamsticks. I'm just wondering if it will work ok with the hamsticks in a mostly vertical orientation. The bottom hamstick would be dropping down between the 20m legs and I dont know if that would affect them or not. Gonna try this out this afternoon once the rain quits

[NQ6U]

You still have your roof, I assume?

[K7SGJ]

Not a problem there. Got a mfj259c i use to tune the hamsticks. I'm just wondering if it will work ok with the hamsticks in a mostly vertical orientation. The bottom hamstick would be dropping down between the 20m legs and I dont know if that would affect them or not. Gonna try this out this afternoon once the rain quits

I'm wondering if the 20 meter legs might act as a ground plane of sorts, and actually enhance the 40m signal somewhat. As Carl said, it shouldn't act a lot different than a multi-band fan dipole. At least as far as impedance goes. But I would think the angle of radiation would be effected. It would be interesting to model the thing on one of the antenna programs. I suspect, as with most antennas, you may also have to do some pruning for optimum performance. Let us know how it works out. It's an interesting concept.

[K7SGJ]

You still have your roof, I assume?

Yes, but it's in the back yard now.

[NQ6U]

Yes, but it's in the back yard now.

That's much more convenient than if it had been in the neighbor's back yard.

[W5BRM]

heheh yep still got my roof. Was listening to the news this morning. The "roof" that was blown off in town here last night was actually just a screen door...LOL Seems whoever reported it was embellishing a bit or something...

That would be nice if the 20m affects the directivity of my 40m. I seem to only get ne/sw signals. I don't get a lot of florida or washington state sigs. but I get a lot of new england and socal.. I think thats because my "vertical" isn't exactly vertical. It has a 10/15 degree list to is as the coax and pvc pipe i run for the coax to keep it 90 degrees from the dipole leg pulls it off center

[KG4NEL]

PA transistors are a lot like buses, they don't come, they arrive.

Sounds like an ex of mine...

heheh yep still got my roof. Was listening to the news this morning. The "roof" that was blown off in town here last night was actually just a screen door...LOL Seems whoever reported it was embellishing a bit or something...

That would be nice if the 20m affects the directivity of my 40m. I seem to only get ne/sw signals. I don't get a lot of florida or washington state sigs. but I get a lot of new england and socal.. I think thats because my "vertical" isn't exactly vertical. It has a 10/15 degree list to is as the coax and pvc pipe i run for the coax to keep it 90 degrees from the dipole leg pulls it off center

Vertically-polarized stuff is interesting. For a while in 2011 I was using a vertical dipole with ten-foot horizontal sections on the top and bottom, fed with 300-ohm line in the middle. Let the tuna take care of the rest.

I have no idea what the pattern was, but it was pretty good into Europe.