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Hi John and others,
Interesting topic.. I also agree with the j-pole. Not to bend any eyebrows. (I also have 300ohm 2M j-pole designs web-posted ) The only comment is the use of 300ohm twinlead for antenna construction. 300ohm twinlead comes in several different variations and the velocity factors are all over the place. So, results vary!! I've answered my fair share of e-mails in the past 5 years, trying to explain this problem to other new Hams. This can really discourage someone that tries to build a first time antenna with the wrong type wire. Stuff to look for: Don't use the "thick stuff": also called the "Heavy Duty" with a heavy thick brown plactic covering. It is very difficult to cut and almost impossible to work with. Do not use the "foam type": with foam covering the wire, between the wire and the outside black plastic casing. Look for the "thin stuff": and the flatter the better. Another thought is to move to a different construction material with a little more consistency: 450ohm ladderline, Solid copper type. Ref: http://home.comcast.net/~buck0/ll_coolj.html Hope this helps others! 73 Steve KB1DIG "John Steffes" wrote in message ... Hal, Your idea using the J-Pole is probabaly the best solution. 1. No radials needed 2. Easy to match using ANY type of feedline 3. Total length is about 3/4 wavelength (about 52") including matching section 4. Easy to contruct We found this URL that may give you an idea regarding contruction. http://w4zt.com/jpole/ John Hal Rosser wrote: If you built a dipole, then it was (most likely) not a quarter-wave - but a half-wave a j-pole may be a good choice given the situation that it needs to be 'out the window' and is uhf or, for that matter, a coaxial half-wave dipole. (strip and fold back 1/4-wave of braid - and weatherproof it) "WolfMan" wrote in message t... I'm Limited To An Antenna On The Front Of My House. Out My Window I Made A Simple !/4 wave Verticle Dipole. Would A 1/2 Wave Simply Be Twice The Length, Using 462/f Mhz, And Would There Be An Advantage With A 1/2 Wave Over a 1/4 Wave ? Thanks --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.770 / Virus Database: 517 - Release Date: 9/27/2004 |