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References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*\[TowerTalk\]\s+VHF\/UHF\s+Common\s+Mode\s+Choke\s*$/: 11 ]

Total 11 documents matching your query.

1. [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Fri, 28 Jun 2019 11:50:19 -0700
I've never been much interested in VHF/UHF, but with the current level of solar flux and the summer static I'm thinking of giving it a try using homebrew antennas based upon DK7ZB designs.  For 6m I'
/archives//html/Towertalk/2019-06/msg00173.html (7,452 bytes)

2. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Fri, 28 Jun 2019 15:32:24 -0700
I recently did some work on chokes for 6M and posted the result to an email reflector devoted to grid chasers for that band. Two turns of RG8-size coax through a 1-in id. #31 clamp-on is optimum for
/archives//html/Towertalk/2019-06/msg00180.html (9,038 bytes)

3. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: Dave Sublette <k4to.dave@gmail.com>
Date: Fri, 28 Jun 2019 18:58:23 -0400
Using a T-match eliminates the need for a choke, for the most part. I have T-matches on everything from 2M to 70 CM. Dave, K4TO _______________________________________________ _______________________
/archives//html/Towertalk/2019-06/msg00181.html (9,841 bytes)

4. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: jimlux <jimlux@earthlink.net>
Date: Fri, 28 Jun 2019 17:47:02 -0700
I've never been much interested in VHF/UHF, but with the current level of solar flux and the summer static I'm thinking of giving it a try using homebrew antennas based upon DK7ZB designs.  For 6m I'
/archives//html/Towertalk/2019-06/msg00185.html (9,551 bytes)

5. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: jimlux <jimlux@earthlink.net>
Date: Fri, 28 Jun 2019 17:49:01 -0700
On 6/28/19 3:32 PM, Jim Brown wrote: I recently did some work on chokes for 6M and posted the result to an email reflector devoted to grid chasers for that band. Two turns of RG8-size coax through a
/archives//html/Towertalk/2019-06/msg00186.html (8,577 bytes)

6. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Fri, 28 Jun 2019 19:28:28 -0700
Can you please explain how a T-Match eliminates the need for a choke?  Fundamentally a T-Match itself is a balanced network, and unless you purposely unbalance it I don't see how it eliminates unwant
/archives//html/Towertalk/2019-06/msg00189.html (9,188 bytes)

7. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: Glenn Pritchard <gpritchard7000@gmail.com>
Date: Fri, 28 Jun 2019 19:33:46 -0700
A folded driven element is inherently 200/300 ohms, if you take the Sinclair or Comprod antennas there is a 96 ohm transference within the element when they talk about open dipole (feed point open) o
/archives//html/Towertalk/2019-06/msg00190.html (11,116 bytes)

8. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Fri, 28 Jun 2019 19:47:29 -0700
The DK7ZB designs I plan to use give a 50 ohm impedance at the center of a single split driven element.  A small amount of gain is sacrificed to accomplish that.  I modeled the designs in EZNEC+ and
/archives//html/Towertalk/2019-06/msg00191.html (11,845 bytes)

9. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Fri, 28 Jun 2019 21:29:26 -0700
Yes, it's a very good material for 6M and 2M. From that table of chokes, click on any part number to see the data sheet. Scroll down to see plots of Zmag for 1, 2, and 3 turns. For practical chokes,
/archives//html/Towertalk/2019-06/msg00194.html (9,297 bytes)

10. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: Máximo EA1DDO_HK1H <ea1ddo@hotmail.com>
Date: Sat, 29 Jun 2019 09:41:16 +0000
Hi Glenn, As you said, folded driven element is around 200 to 300 Ohm impedance. To transform that to 50 Ohm is not a balun, it is a impedance transformer. You can transform 300 Ohm to 50 Ohm and sti
/archives//html/Towertalk/2019-06/msg00196.html (12,983 bytes)

11. Re: [TowerTalk] VHF/UHF Common Mode Choke (score: 1)
Author: Wes <wes_n7ws@triconet.org>
Date: Sat, 29 Jun 2019 06:41:26 -0700
Back when I was on EME, we didn't have the knowledge or material to use ferrite chokes, but that might be the way to go now.  On my one balanced-line fed array, I manufactured a coaxial sleeve balun
/archives//html/Towertalk/2019-06/msg00197.html (11,594 bytes)


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