Towertalk
[Top] [All Lists]

Re: [TowerTalk] Which Balun with the TH7DXX

To: towertalk@contesting.com
Subject: Re: [TowerTalk] Which Balun with the TH7DXX
From: K8RI <K8RI-on-TowerTalk@tm.net>
Date: Mon, 22 Jul 2013 22:32:23 -0400
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
On 7/22/2013 7:14 PM, Bert Almemo wrote:
4-5 turns with 4 x 2.4" OD #31 ferrites is more effective than the 30 turns
on the PVC pipe! Probably double the choking impedance!

I haven't looked the specific number of cores and turns but done correctly you should be able to get around 5000 ohms isolation with the #31 cores.

73

Roger (K8RI)


73 Bert, VE3NR



-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Peter
Voelpel
Sent: Monday, July 22, 2013 6:55 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Which Balun with the TH7DXX

A solenoid winding made of coax is more effective then those 4 wraps.
I use SCF12-50 Cellfex to wind my choke baluns.
30 turns on a pvc tube of 4-5" diameter do the trick (2000 ohms at 14MHz).

73
Peter

-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim
Thomson

##  coiled up coax is not the answer either, the Z is  too low.   Like
gerald sez,
the wire leads on the baluns output is part of the total DE ele  length.
So if using coax... factor that in...and make the Y the correct length.

##  4 wraps  of  213 U around   4 x 2.4 inch OD    type 31 ferrite will do
the trick
for a balun....

_______________________________________________



_______________________________________________
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

<Prev in Thread] Current Thread [Next in Thread>