Hig Gain Double Discone Antenna

[rwl48]

In the never ending pursuit of the best base antenna. What do you guys and girls think of this one?







http://radio-ware.com/

 

[iMONITOR]

Someone had ask about a similar design not too long ago. There was a lot of criticism over the design for various reasons, basically claiming it was snake-oil, etc.

However, I was surfing the web the other night in search of links related to MilAir, and stumbled across a site with pictures of a military installation that was using something that looked almost identical. I'll try to find that link and post it later.

 

[SkipSanders]

Discone gain = 0 db. Two discones, maybe you could get 1 db.

If you want gain over a wide bandwidth, you use log periodic beam antennas.

 

[zz0468]

A discone is actually about 1dbi gain over an isotropic radiator, or about 1 db loss referenced to a dipole. So... 2.8 db gain over a conventional discone= 1.8 db over a dipole, that is, if you believe the claims.

I think the biggest inherent advantage to that antenna is that it doesn't give the birds a place to sit.

 

[Air490]

I have used a one of those antennas for about the last three years. I use it primarily for VHF and UHF airband monitoring. It does a great job, and is definately better than a discone.

It is actually a bi-cone rather than a double discone, as there is no "disc" in the design.

 

[prcguy]

Air490 is right, it’s a Bicone and has little to do with a Discone. I have also had one for about 5yrs and would have taken it down and given it away years ago but I’m too lazy to go up and fetch it. My experience with this antenna is not better than a similar sized Discone overall. It has a so-so match at a few discreet frequencies where its performance perks up a little, otherwise you wouldn’t want to transmit on this thing. This could also cause problems if you place a wide band preamp at the antenna. Some preamps can oscillate if not terminated with a reasonable match and the Nevada is all over the place. A properly designed Bicone has a balun and a complex matching network and at best covers about a 4:1 frequency range compared to the Discone at about 8:1. The Nevada “Double Discone” is just a bunch of elements sticking up connected to the connector center pin and a bunch sticking down connected to ground with no matching network. Compare the Nevada to a real Bicone like this: http://www.rfcomm.harris.com/products/antennas-accessories/rf-9070.pdf
I have a Harris 9070 and it stands 6ft tall and dwarfs the Nevada. How do they figure the Nevada covers 25-1300MHz when the Harris is only rated from 100 to 400MHz and they apologize for the degraded specs if you stretch it from 90 to 470Mhz? Did someone mention Snake Oil?
prcguy

 

[iMONITOR]

Compare the Nevada to a real Bicone like this: http://www.rfcomm.harris.com/products/antennas-accessories/rf-9070.pdf
I have a Harris 9070 and it stands 6ft tall and dwarfs the Nevada.

prcguy

I didn't see any prices on their site. If you don't mind me asking, what was the cost?

Thanks!

 

[prcguy]

On the Harris? I don’t have the current price but probably around $1200 range new. I picked mine up surplus for cheap. It's too nice to put on the tower so it only comes out for special occasions.
prcguy

I didn't see any prices on their site. If you don't mind me asking, what was the cost?

Thanks!

 

[Air490]

Don't get me wrong... I am not saying this is a brilliant antenna, only that I found it was better than a discone. I think this was mainly due to the different radiation pattern making for better reception of signals from close to the horizon.

I am still continuing my perpetual search for the best VHF/UHF airband antenna!