[TowerTalk] TowerTalk Digest, Vol 67, Issue 82

Marinus Loewensteijn zl2ml at hotmail.com
Fri Jul 25 01:22:19 EDT 2008


Thank you for this information, it is exactly the kind of information that I am looking for.

Yes, I am totally alert to the fact that anyone can claim anything on the internet, unlike in the old days when there was a lot of peer review and you just could not publish without being scrutinised.

Means that I will need to go to plan B and that is put up a rotatable dipole except it will be in a permanenet fixed direction.  

Question will now be if I go with the CushCraft or the Hy-Gain. Unfortunately neither of these can be viewed locally and by the time they are landed here they are about triple the US price. I am gving serious thoughts towards just obtaining the crucial parts ( synthetic parts ) and then homebrew the rest. Fortunately the biggest aluminium wholesaler is just 3 Km  down the road from here.

Input towards this idea will also be appreciated,

73, Marinus ZL2ML

> From: K4SAV 
> Subject: Re: [TowerTalk] Linear loaded KE4UYP vertical
> To: towertalk at contesting.com
> Message-ID: 
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> Don't believe everything you read in print. I just modeled an 80 meter
> version of that antenna, using the recommended dimensions, top wire at
> 31 ft and 65 ft long, with 82 ft of wire in the vertical portion with
> the bottom wire 5 ft above ground.
> It resonated at 3.69 MHz with an impedance of 26 ohms. He claims the
> longer wire on the vertical side off-center feeds the antenna and raises
> the impedance to 50 ohms. Didn't work for me. If you matched the
> antenna to 25 ohms the 2 to 1 SWR bandwidth would be about 70 KHz. (He
> claims 300 KHz). The gain is 2.9 dBi straight up. (He claims 1 dBi.)
> 2.9 dBi is about the same as an 80 meter dipole at 18.5 feet. He claims
> it is 80 to 85% efficient. EZNEC calculates 4.13 dB loss. That's
> equivalent to 38.6% efficiency. He claims it is totally
> omni-directional. At 30 degrees elevation it has a F/B of 3.6 dB.
> I didn't include the feedline or any metal support poles in the model.
> I didn't do the 160 meter version, but I would expect much poorer numbers.
> Jerry, K4SAV

Find singles in your area with Match.

More information about the TowerTalk mailing list