This is how it goes. First, i had high SWR, by any calculations. I try to made two versions of antennas: One with just hot on top of 1/4 element and one version with 1/4element with short hot and cold end. with Slim Jim, i got good results, SWR a little bit high but ok (1.6) and had good range. With co-co antenna i had problem with sensitivity. Yes, it was only 4 elements. SWR issue is solved with NO turns, rings or whatsoever! Point is than when cable EXIT from balun (copper tube) (i used rg58, .66 v factor) it has to have some xx cm length before cut and connect to connector (i didnt have female N so used SO239). There i connected RG213 and with a few different lengths of RG213 i got SWR between 1.1 to 1.3 max on same band. BUT swr is not a big problem (usually hams magnify that problem) i am couriouse, since i have my Rohde & Schwarz CMS54 here, i can try to generate some low power signal and to do measurements with co-co and some simple 1/4 element to see difference. BUT, is there anything that i am doing wrong? any tips? As you can see below, there are two links for antennas that i made... maybe i did something wrong? If anyone can help me, i can upload some pictures of mine antennas to see what problem is... Thanks in advance!!!!!
----- Originalna poruka ----- Posiljalac: Peter Dakota Summerhawk <[EMAIL PROTECTED]> Datum: Cetvrtak, Jul 31, 2008 8:58 Tema: RE: [Repeater-Builder] Re: UHF antenna Primalac: Repeater-Builder@yahoogroups.com > A real simple test I had for deaf antenna: this was on 2M so I > stripped a > section of coax off eh end to form a 1/4 wave antenna and > connected it to > the original run of coax to make sure I could be heard with a > few short > tests. Turns out it was the antenna in the end and not the coax > like I > thought. Might give it a try and see if that doesn't work for > you in a > pinch. > That way you know if it's the antenna or another problem. > Just throwing out ideas. > > -----Original Message----- > From: Repeater-Builder@yahoogroups.com > [mailto:[EMAIL PROTECTED] On Behalf Of Milan Pavlica > Sent: Wednesday, July 30, 2008 8:32 AM > To: Repeater-Builder@yahoogroups.com > Subject: [Repeater-Builder] Re: UHF antenna > > Is it possible that no one have pictures of its home made antennas? > As i wrote, i have a problem with sensitivity, think that > antenna is > "deaf". Will try to compare with Celwave antenna and Rohde&Schwarz > CMS54 test-set as receiver to see differences.... > Please help me... TNX in advance! > > > --- In Repeater-Builder@yahoogroups.com, "Milan Pavlica" > <[EMAIL PROTECTED]> wrote: > > > > Hello! > > I made UHF coax collinear antenna, two version, one is from > > http://www.repeater-builder.com/antenna/wa6svt.html > > and second is from > > > http://www.para.org.ph/membersarticles/DU1ANV/VHF%20Collinear%20Antennas.htm > > in both cases i can get good SWR but i am not so sure did i > made it OK > > (have a feel that it is deaf on receive) > > I am asking, if anyone played with this stuffs (i made > 4elements, for > > start only with RG58), maybe with some tips and pictures, just > to see > > am i doing something wrong.... > > THANKS IN ADVANCE! > > Not to disturb list, please use private mail. > > THANKS AGAIN! > > YU7XW > > > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > mailto:Repeater-Builder- > [EMAIL PROTECTED]
