[TowerTalk] TH-7DX Balun

[Jim Thomson]

Date: Mon, 21 Jul 2014 05:14:38 +0200
From: LB3RE LJ3RE Stein-Roar Brobakken <post at lb3re.com>
To: Byron Tatum <bjtatum1 at att.net>
Cc: "TowerTalk at contesting.com" <towertalk at contesting.com>
Subject: Re: [TowerTalk] TH-7DX Balun

HiIts a simple 1:1 current balun You can also use simple RF choke with 7-8 turn of coax on 3-4" diameter RG8/RG213.? Then i use RFI clips 15mm about 10 pcs from ebay is cheap instead of huge cost of something crappy.   The BN4000 been discussed here too in 2008  http://lists.contesting.com/_cq-contest/2008-08/msg00106.html    

---Sent by iphoneLB3RE LJ3RE K3RAG ex: LA6FJAwww.lb3re.com ~ Rag ~ Stein Roar Brobakken e-mail:post at lb3re.comhttp://la5o.wordpress.comwww.contesting.no


### 7-8 turns of  213u on  3-4 inch diam  isnt gonna  do a damn thing on 80m band..waste of time.  Stuff 4-5 turns of the same 213 u  through 8-10 x 2.4 inch od type 31 cores..and then u have the real deal.

##  The BN-86 is fubar.    I destroyed 3 of em back in the 70s..with just low swr and 1900w  output cw  + ssb.  I had one on my 204ba, another one on the 80m inverted vee....and the 3rd one on my 40m half wave sloper.   I opened em up, and the magnet wire was burnt to a crisp !   If hy gain – mfj is still selling the bn-86 they are complete idiots.    And ditto with the w2au  big signal balun...more junk.  

Jim  VE7RF