Topband: Beverages 2 basic questions

[ZR]

Mike, Im pretty sure a group buy would convince the manufacturer to sell 
them. Supposedly an Ebay seller has an "exclusive" but since our use is non 
competitive to his SWL and cave dweller ham customers it could be 
negotiated.

The large diameter steel ones work well but rust away in 15-18 months in 
this area of acid rain and salt water fogs. Using spray cans of Rustoleum, 
etc would be time consuming and likely needing periodic touchups. Plus the 
steel further slows down the incoming wave so it might not be possible to 
build an effective 1 wavelength + version. I had 5 stretched over about 175' 
and calculated a Vp of .57 but it sure worked gangbusters for those LP 
sunset signals over Africa. For many I was the only US station working them 
and the almost total lack of even EU QRM was a huge advantage. Switching to 
a 750' regular Beverage pointing right down the Med heard only a EU din; 
I'll let you estimate the F/S rejection of the Slinky.

Using a high frequency local BCB station right off the back the null was at 
1250-1300 Ohms using a 2K pot and replaced with 3 x 3900 Ohm 2W carbon 
resistors. Id guesstimate the general F/B to be over 20dB on 160. My feeling 
is that performance could not be duplicated by various other loading 
methods. If somebody wants to make real world comparisons it might be 
beneficial.

Carl
KM1H




----- Original Message ----- 
From: Mike Waters
To: ZR ; topband
Sent: Saturday, December 01, 2012 2:41 PM
Subject: Re: Topband: Beverages 2 basic questions


Please let us know how that works, Carl. I'd love to experiment with a 
Slinky.

If brass Slinkys aren't available anymore, then we could wind one from some 
#14 or #12 solid copper wire using a long piece of plastic pipe as a form. 
Close-wind it first, then stretch it to the desired (?) pitch.

73, Mike
www.w0btu.com


On Sat, Dec 1, 2012 at 9:52 AM, ZR <zr at jeremy.mv.com> wrote:

Next year Im planning to try a couple of Slinky Beverages again in order to 
get a 2-3 wave electrical equivalent for particular paths and narrow the 
beamwidth





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