[SFDXA] Today's antenna party, and a Dayton request

[Ed Callaway]

Mike,

I appreciate your generous offer, but I've already got the wire on order and delivery arranged.  I will, however, keep you in mind for the Association's future antenna projects.

Thanks, and 73,

Ed N4II

-----Original Message-----
From: Mike Williams [mailto:mj451 at bellsouth.net] 
Sent: Friday, April 13, 2012 3:11 PM
To: Ed Callaway; SFDXA at mailman.qth.net
Subject: Re: [SFDXA] Today's antenna party, and a Dayton request

Hello Ed,

I have about 300' of 12 ga marine primary wire with black insulation; new when I bought it and never used it for antennas or anything else.  The SFDXA can have it for the antenna you mentioned; this stuff doesn't solder well unless you use a torch and is meant to be used with crimp connections.  When installed properly, it will last forever...well, almost.


73 de W4DL   Mike



----- Original Message -----
From: "Ed Callaway" <ed at sunrisemicro.com>
To: <SFDXA at mailman.qth.net>
Sent: Thursday, April 12, 2012 4:10 PM
Subject: [SFDXA] Today's antenna party, and a Dayton request


> Today KE4PT and I went to K4FK to install a balun on the 30/40m dipole 
> pair, and to put the 80/160m dipole pair back up on the tower, also with a 
> balun.  The north half of both the 80 and 160m dipoles has fallen down 
> from the tower, as has the south side of the 80m dipole.
>
> We added a balun to the 30/40m dipole pair successfully.  It's possible 
> that I am deceiving myself, but I think I saw a noise reduction of about 
> 10 dB compared to the prior value.  (It's still 10 dB higher than 20m, but 
> still.)
>
> When we went to the North tower to begin work on the 80/160m dipole pair, 
> I was disappointed to find that the 160m dipole was made of FLEX-WEAVE. 
> FLEX-WEAVE is made of many fine, soft-drawn copper wires arranged in a 
> mesh, not unlike solder wick, which gives it its flexibility. 
> Unfortunately, it also gives it a very high surface area-to-volume ratio, 
> so that once oxidation (corrosion) starts, it very rapidly consumes the 
> wire and failure is certain.  It was this mechanism that caused the 
> failure of the antennas on the North tower (and also of the 30/40m 
> FLEX-WEAVE dipoles on the South tower last year.)
>
> Fortunately, the 80m dipole uses #14 AWG hard-drawn copper, complete with 
> insulation.
>
> So, in short, we need to replace the 160m dipole, which means that I have 
> a shopping request for someone going to Dayton:
>
> 300 feet of Wireman p/n 531, Toughcoat 'Silky' #13 AWG, 19 strand 40% CCS 
> wire.
>
> Is someone going to Dayton that can pick this up for the Association? 
> Reimbursement, of course, is assured.
>
> Thanks, and 73,
>
> Ed N4II.
>
> ______________________________________________________________
> South Florida DX Assoc.
> SFDXA WebSite: http://qsl.net/k4fk
> SFDXA Repeater 147.33+ 103.5 Tone
> To Post: mailto:SFDXA at mailman.qth.net
> Subscribe or UNSubScribe:
> http://mailman.qth.net/mailman/listinfo/sfdxa
> DX Net Wed 7:33 PM Repeater
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html