Discone sharing a mast with uhf/vhf antenna

[Glennscan]

Hi,
I'd like to get a discone antenna and was wondering if it can be mounted
to a mast which already supports a uhf/vhf antenna that I use for my
television?
glenn

 

[SAR923]

A discone really needs to be located at the top of a mast, away from other antennas. I'm assuming you have a normal home mast and not a professional model that allows you to "L" off the main mast to mount an additional antenna. As long as you get the discone at the top of the mast and the drooping radials are at least a couple feet above the nearest additional antenna, it should work.

 

[Glennscan]

Thanks for the info Jim.
Just below my existing antenna, I'm wanting to add a horizontal extension arm,using a homemade angle iron/u-bolt setup.This will hold the discone.Does this sound possible?

 

[SAR923]

The "L" bracket will work but most discones are about five to six feet tall if it has a low band vertical element. It's hard to tell from looking at your picture how tall the mast is but, if it has enough clearance from the roof, the mounting should work. As I said, it won't be ideal since you will get some interaction from the TV antenna elements. I also can't tell what type of guy wire system you're using, if any, but you'll want to increase your guy wires if you live in a part of the country that gets windy. Discones don't have a lot of wind resistance but there are so many elements that a high wind can set up some resonance between the elements and the resonance can put a fair amount of stress on the mast. I've got a 40 foot mast with a three guy wire system at the top and 20 feet down and, even with that, a high wind can get things rocking and rolling.

 

[Glennscan]

OK,I'll rethink this and may try to mount it on a dedicated mast off of my
chimney.
Thanks

 

[OutPost]

Discone On Top Of My Other.......

I just placed a Centerfire Discone at the top of my 25' mast. Below it, maybe a foot, is an Wineguard FM (two element) antenna, and below that a Radio Shack Ground Plane.

My reception on the Discone is better than the lower ground plane, but only on the aviation band (118.0 to 135.0). My 400 mhz range is slighty less desirable than the lower ground plane, but thinking that because the Discone is actually for MURS transmissions, Centerfire states that reception range for that antenna is 25 to 1200 mhz.

I was going to pull it down, but since the aviation band is better, I will keep it solely for that band on one scanner and the other scanner will stay on the older ground plane. I'm wondering if the FM antenna in the middle is the reason for slighty less reception than my lower ground plane??

Dave
West Tennessee