Glenn Little WB4UIV <[EMAIL PROTECTED]> wrote: >Why would you mount the second antenna upside down??? > >Is this to keep the coax to the two antennas close together and gain the >loss through the coax to the upside down antenna?? > >Is it to ensure early failure of the upside down antenna because of >moisture buildup?? > >Is it to cause the signal to go toward space rather than back to the ground >due to any possible down tilt built into the antenna?? > >I would use folded dipole antennas due to their grounded nature. The >colinear antenna tend to have problems with flexing and lightning. When all >but the bottom quarter wave section is disconnected due to flexing or >lightning, there is no way to determine that you have an antenna problem >from the ground. > >Just my thoughts. YMMV. > >73 >Glenn >WB4UIV >Over 30 years in the amateur service. Kh6jkg>Thanks for your emails, Glen, WB4UIV, & Kris Kirby, KE4AHR <[EMAIL PROTECTED]> Over the years, we have installed dual-band comet or X-50. Since we simulcast on VHF & UHF, we use dual band antennas, one feed line & a diplexer, which is connected to each duplexer or two separate antennas, (1-VHF, 1-UHF) with two feed lines, on different towers, to each repeater.
I will keep your comments in mind, when mounting separate Uhf/Vhf antennas systems on the same towers. One X-50 has great range, it must be the good ground system on the Cell tower. 73's, Jim Kh6jkg. >At 07:32 AM 01/29/06, you wrote: >>On Sat, 28 Jan 2006, Jim Connell, KH6JKG wrote: >> > I have a preference for Station Master antennas. Although, most of our >> > sites are simulacasting on VHF & UHF. So, dual-band antennas where also >> > used over the years. >> >>You may be able to hack around this if you can get permission to install >>another antenna below your current antenna. Then get a diplexer, place it >>up the tower and mount the other band's super stationmaster upside-down >>below the primary one. You'll have to see about water drainage issues, of >>course. >> >> > On the sites with unused parts of these dual-band antennas, should the >> > unused section of the antenna be terminated? With a short or 50 ohm >> > termination? >> >>Seems preferable to do so as some sites have reported interference issues >>from unterminated coax in the building attached to antennas on the tower >>no longer in use. >> >>-- >>Kris Kirby, KE4AHR <[EMAIL PROTECTED]> >> "BIG BROTHER IS WATCHING YOU!" >> This message brought to you by the US Department of Homeland Security __________________________________________________________________ Switch to Netscape Internet Service. As low as $9.95 a month -- Sign up today at http://isp.netscape.com/register Netscape. Just the Net You Need. New! Netscape Toolbar for Internet Explorer Search from anywhere on the Web and block those annoying pop-ups. Download now at http://channels.netscape.com/ns/search/install.jsp Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
