Jeff: Kathrein-Scala Antennas makes good heavy duty yagi and a log periodic antennas with radom and without. I have used them before. They will survive most mountain tops with ice and salt water sprays. They are expensive.
Fred W5VAY _____ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff DePolo Sent: Thursday, July 01, 2010 11:29 PM To: Repeater-Builder@yahoogroups.com; repeat...@yahoogroups.com Subject: RE: [Repeater-Builder] Re: [Repeaters] Looking for HD 440 Yagi I'll echo most of Dave's comments, and add a few... > The MYA's tend to have finicky tuning, and I've never seen one sweep > correctly out of the box. Close enough probably, but not optimized > either. The BMOY's are broad band, with one model covering 406-440 > MHz and another from 440-480 MHz. Maxrad stopped making the MYA antenna that I used a lot - MYA43012 - 12 elements, 430-450 MHz. Now you can only get the 12 element model in 450-470 range :-( I never had much problem tuning up the MYA yagis, but as Dave said, they usually weren't tuned well out of the box. Sealing up the connector is a PITA; I always removed the rear (reflector) element, removed/loosened the hardware to allow the feed to be slid to the rear of the boom, and then proceeded to put my jumper on it and seal it up right before sliding it back into position and tuning it. I'm now buying Sinclair SY307 series and Comprod 430-70 yagis (7 element, 10 dBd each, very close to being clones of each other) at about $140 each. Have about a dozen in service and more in stock for upcoming projects. My only complaint thus far is that they seem to not be consistant on what kind of connector is on the end of the pigtail - some came with N males, some with N females - picky picky. The Antennex gamma-fed UHF yagis are real dogs. The tuning is extremely touchy. Minor changes in placement of the jumper/feedline throw the tuning all over the place, and slight changes in distance from the mast and/or changing polarization will require retuning. The Sinclairs and Comprods are mostly immune to detuning in that regard, and always sweep well across the entire spec'ed range. I bought four of the 12-element models (two silver, two gold) when I found out I couldn't get the Maxrads any more, and they're still sitting in the warehouse, I wasn't happy with them after I tested them. I, too, had/have a lot of the old Larsen's in operation (5 and 8 element), but they don't make the ham splits any more. Although they aren't built as rugged as some of the others mentioned, they've held up pretty well. I just took down two of the 8-element models that had been up on a mountain for about 15 years and, aside from a couple of bent elements from falling ice, had held up pretty well. I replaced them becuase a) they were getting old and beat up, and b) I wanted to replace the feedline runs anyway so I figured I may as well swap out antennas at the same time, one less 200+ mile trip and tower climb to make in the future. I still have four of them at a site that have been up for just about 20 years now and they're still working. --- Jeff WN3A
