102" with V radials

[dime196604]

Yes i am back again with another antenna idea to throw by you guys.. so here it is i live in an apartment on the ground floor with a 15ft wide and about 4ft deep deck with walls on both sides of the deck and a 4ft high wood railing in the front of it.. So its not a good place to start. i have on horizontal dipole with coiled ends already. but i need some thing vertical to talk to the locals . So here is my idea. Have one 102" whip about 2 ft off the ground mounted to the wood railing. i can't go any higher with it cuz there is a deck above me too. but any way have the one main vertical 102" whip with 2 102" radials mounted from the same feed point but coming up on both side of the driven element kinda like a very wide V for the radials not to close to the driven element at the ends. the radials at the same feed point 2ft off the ground and the ends of the radials about 4 to 5 ft off the ground. you guys think it is workable? Any signal strength or weakness due to the design? (other than its too close to the building and not high enough off the ground) Can't wait to see what you all think about this one.. Its ether a winner or gonna make me feel dumb.. you guys decide

[dime196604]

So not a good idea?

[231]

Not sure? Honestly I'm kinda' confused by your post? Are you talking about adding two main radiating elements next to the center radiator? I've read your post like 3 times but still don't quite get it. How about a drawing or something?

[dime196604]

no just the one main element in the middle the two ground radials coming you on each side of it. so the two ground radials would a big V with the main driven element sticking strait up in the middle of the V. so its a ground plain antenna but with the grounds angeled up instead of down.. you get what i'm saying now?

[Night Crawler]

the two ground radials would a big V with the main driven element sticking strait up in the middle of the V. so its a ground plain antenna but with the grounds angeled up instead of down.

That won't work.

[Ronin]

If I am reading that correctly, running 2 more 102" whips in a V on either side of the main vertical 102" radiator won't work. You need to have some kind of ground plane or counterpoise for that vertical radiator to work against. The 102" whips would have to be ran away from the vertical radiator. Downwards...not upwards.

I would say save the money on 2 more 102" whips and simply run about 108" of wire on each side of the vertical radiator away from the vertical at an angle towards the floor. Even more simple would be to just make an inverted V dipole, tack it to the ceiling and run the ends at an angle towards the floor. I ran an inverted V in the attic for years as a secondary antenna. Tests with my Imax (which was 20 ft off the ground at that time) against the inverted V was only a few S-Units in all directions.

OR... make both antennas and run some tests to see which one works best. You might even find that some signals come in better on one antenna than the other.

[dime196604]

ok thanks all i needed to know. would and inverted V be better for talking to locals who have horizontal polarization?

[Lost Ram]

Do you have an SWR meter? This device helps. You could get some solid cooper wire from the local home improvement store and try to make a 102" whip di-pole with the ground element or elements not being the traditional straight configuration. As it is know you have one with coiled ends. The star duster antenna has three 102" ground radials at about 150 degrees(ish not a quote). I know you don't have the room for that but think about a car, it could be a chop job with a 4 foot high roof and still get a good SWR because it has enough counterpoise or ground area. I have seen some crazy short/configured ground side di-poles in my day, they my not have had the best gain but they provided a workable solutions to antenna restrictions. check this post about a spiral antenna, [Please login or register to view this link] . Strange but its usable. Heck maybe your wooden deck needs some cooper wire weaving on the bottom 2 foot of it.

[Ronin]

Most things you read regarding the inverted V will say that it is vertically polarized. I would say from using several over the years they are primarily vertical (and omni-directional), but exhibit some horizontal characteristics (directional off the broad side). All I can say is since they are so simple to put together, try one. Over the past 7 years, in two different homes, I have always had an inverted V up in the attics. Since I use my Imax for ham as well as CB, the "V" allows me to keep the CB up while tuning around on other bands on the Imax. They are relatively cheap and they work pretty darn well too!

I still say grab some wire, make radials for your 102" whip, and make an inverted V as well and run them through a 2 position coax switch and do some testing. I know if I had only a deck like yours to mount antennas on, that's what I would do.

Oh, and BTW, make a coaxial balun (air balun) by looping about 6 or 7 turns of coax into about 4" in diameter and tape the coils together right at the feedpoints for both antennas. This will help keep stray RF from coming back down the coax and into your shack. It can also help with RFI in case you start coming through the neighbor's stereo, computer speakers, etc.

['Doc]

Just a few comments.

Inverted 'V' antennas are basically a horizontally polarized antenna. There may be -some- vertical polarization associated with it, but not much at all. It really is a matter of how it's "hanging". A little 'droop' of those legs when horizontally 'hung' merely lowers the input impedance (very common way of doing it!). If it's hung vertically, and you want to reduce the input impedance a bit, raise that bottom leg to some angle where the results are what you want (also a very common way of doing it!).
If you want a vertically polarized antenna, then use one, doesn't much matter if it's home-made or commercially made, one radial, two, twenty seven, however many you want, it's basically the same.
I like to make antennas out of wire, it's cheap and easy, work as well as using tubing, simpler in most cases. No reason why you can't make the radials out of wire either, it works just dandy.
Got a plastic bottle cap that's large enough to put two holes in it? One hole for the vertical section, the other hole to thread the radials through (twice as long as one radial, position so it's centered in that hole, then give it a twist to hold it there). Center conductor of coax to the vertical wire, braid to the radials, solder and hang the thing. Nylon cord make nice insulators! What kind'a wire? Whatever you happen to have enough of, size doesn't make any difference except that it has to be strong enough to support it's self. Make that vertical part about 104 inches long, then use the 'droop' of the radials to find a good SWR. That's the basic idea. From there you 'finagle' things till they work. You end up with a 'dead-nutz' typical 1/4 wave groundplane antenna. May not be pretty, but do you really care as long as it works? About 30 feet of wire, one plastic bottle cap, some coax and string/cord. $10 maybe?
- 'Doc