Dan, thanks for that link.
What are the specs of the Aztec sleeve balun? From the table it appears to
use 73/77 mix ferrite which peaks at low HF. For 10-20M a 43 mix would
improve the performance. Alternating mixes on the coax gives excellent 2-30
mHz performance.
Around 1989-90 I tested a wide range of ferrites for sleeve baluns using a
HP Vector Impedence Meter and wrote the results up for the YCCC, dont
remember when/if it was published; I moved just after. One size did not fit
all! My goal was to obtain a minimum of 1200 Ohms reactance which was easily
met.
Carl
KM1H
----- Original Message -----
From: "Dan Hearn" <dhearn@air-pipe.com>
To: "Clint Talmadge" <unclebudd@bellsouth.net>; <towertalk@contesting.com>
Sent: Thursday, June 14, 2007 1:44 PM
Subject: Re: [TowerTalk] Ferrite Balun on a LPDA?
> Clint, our club web page www.sdxa.org has a link to a set of impedance
> measurements of bead and solenoid baluns at different frequencies. Click
> DX
> tips and you will be led to the measurements. 73, Dan, N5AR
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com]On Behalf Of Clint Talmadge
> Sent: Thursday, June 14, 2007 10:00 AM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Ferrite Balun on a LPDA?
>
>
> I am close to putting my Tennadyne T-6 back up. When I took it down it had
> the prescribed Coax Balun on it and it showed it's age. For the last month
> or so I have had the antenna on a short perch in the yard with a Ferrite
> Bead Balun on it and it sweeps fine using an analyzer and I have even made
> a
> few DX contacts on it. The balun I am using is a W2AU by Unadilla. I have
> searched different archives and the only one with any significant
> information is one I started on eHam some years ago.The old Tennadyne
> maker
> specifically said he had not tested a ferrite balun and did not recommend
> them. The reasons I would like to use the Ferrite Balun are:
>
> Lower profile - less wind resistance
> Longer life - better built than my taped Coax Balun
> Better Balance - the antenna is much closer to being balanced (weight
> wise)
> with the Ferrite Balun
>
> There is precious little written about feeding LPDAs. What little I have
> read does not address this.
>
> I am open to suggestions as the antenna will not go up till some time in
> early July.
>
> Clint - W5CPT
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|