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940029.txt
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1994-11-13
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Date: Fri, 11 Feb 94 04:30:23 PST
From: Ham-Ant Mailing List and Newsgroup <ham-ant@ucsd.edu>
Errors-To: Ham-Ant-Errors@UCSD.Edu
Reply-To: Ham-Ant@UCSD.Edu
Precedence: Bulk
Subject: Ham-Ant Digest V94 #29
To: Ham-Ant
Ham-Ant Digest Fri, 11 Feb 94 Volume 94 : Issue 29
Today's Topics:
BALUN FOR 2-M YAGI
CB and my Stereo HELP!!!!
Predicting inductor self resonant freq?
RG8 & PL259
Send Replies or notes for publication to: <Ham-Ant@UCSD.Edu>
Send subscription requests to: <Ham-Ant-REQUEST@UCSD.Edu>
Problems you can't solve otherwise to brian@ucsd.edu.
Archives of past issues of the Ham-Ant Digest are available
(by FTP only) from UCSD.Edu in directory "mailarchives/ham-ant".
We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party. Your mileage may vary. So there.
----------------------------------------------------------------------
Date: Wed, 9 Feb 94 20:49:59 GMT
From: unogate!news.service.uci.edu!usc!howland.reston.ans.net!math.ohio-state.edu!cs.utexas.edu!swrinde!sgiblab!twg.com!eco.twg.com!psinntp!newsserver.pixel.kodak.com!kodak!ornitz@@mvb.saic.com
Subject: BALUN FOR 2-M YAGI
To: ham-ant@ucsd.edu
In article <2j64ii$5ip@granny.mdd.comm.mot.com> shane@mdd.comm.mot.com
(Hugh Shane N7UAX) writes:
>Can anyone suggest a design for matching a 50-ohm coax feed to a six beam,
>2 meter Yagi. The balun designs I've seen all seem to be restricted to
>frequencies less than 100MHz. There must be a classic technique, I just
>can't find it!
The classic VHF balun technique is the quarter-wave sleeve balun. In old days
these were often called beer-can baluns, so named because steel beer cans
were soldered together to form the outer sleeve. KLM and a few other companies
sold these commercially but they are easy to build with copper tubing and pipe.
Design information can often be found in the older ARRL VHF manuals. 73
Barry WA4VZQ
-----------------
| ___ ________ | Dr. Barry L. Ornitz WA4VZQ
| | / / | | Eastman Chemical Company
| | / / | | ECC Research Laboratories, Engineering Research Div.
| |< < K O D A K| | Process Instrumentation Research Laboratory
| | \ \ | | P. O. Box 1972, Building 167B
| |__\ \________| | Kingsport, TN 37662 (615/229-4904, FAX 615/229-4558)
| | INTERNET: ornitz@kodak.com
-----------------
Eastman Chemical Company is no longer a part of Kodak, now being an independent
company. Kodak is letting us use her Internet connection until we get our own.
------------------------------
Date: 9 Feb 1994 16:43:24 GMT
From: ucsnews!sol.ctr.columbia.edu!news.kei.com!ub!dsinc!netnews.upenn.edu!jake.esu.edu!marx.esu.edu!nerk@network.ucsd.edu
Subject: CB and my Stereo HELP!!!!
To: ham-ant@ucsd.edu
My speakers pick the CBs of trucks that go by on my street. Does anyone
know how I can stop this?
thanks. please reply directly.
--
---
Commit Random Acts of Kindness & Senseless Beauty
========================================================
Isaac Csandl <nerk@esu.edu> PGP Key availble by finger.
------------------------------
Date: 10 Feb 1994 19:54:54 GMT
From: agate!howland.reston.ans.net!vixen.cso.uiuc.edu!sdd.hp.com!hpscit.sc.hp.com!rkarlqu@network.ucsd.edu
Subject: Predicting inductor self resonant freq?
To: ham-ant@ucsd.edu
In article <CKLw2C.MIr@hpcvsnz.cv.hp.com>, Tom Bruhns <tomb@lsid.hp.com> wrote:
>
>Anyone out there have any reasonably accurate formulas for
>_predicting_ the self resonant frequency of an air-core
>(self-supporting) inductor, given the geometry? Yes, I
>can make measurements, but I want to predict what I will
>get so I can wind the coil I need, then just measure to
>verify/tweak.
>
>73, Tom -- K7ITM
You can start out with the fact that an upper bound on the SRF
will be the frequency at which the length of the wire in the
coil (not the length of the coil) is a quarter wavelength.
Rick Karlquist N6RK
rkarlqu@scd.hp.com
------------------------------
Date: 10 Feb 1994 17:57:37 -0800
From: nwnexus!tedt@uunet.uu.net
Subject: RG8 & PL259
To: ham-ant@ucsd.edu
Recently, I was preparing some RG 8 coaxial cable to solder into PL259.
I found that the center core conductor which consisted of several fairly
stout wires, would not go through to the tip of the 259.
I was forced to cut off a couple of strands.
Will anything blow up?
Ted
------------------------------
End of Ham-Ant Digest V94 #29
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