Hi Tim, My first suspect would be the cable from the duplex er feeding the 7/8. I have problems there more than anything. Although the 2.1 swr is a bit high I would shoot the easy target first.
BR _richard ________________________________ From: tahrens301 <tahr...@swtexas.net> To: Repeater-Builder@yahoogroups.com Sent: Tuesday, September 1, 2009 3:03:29 PM Subject: [Repeater-Builder] Antenna SWR = Desense? Hi folks, Just a bit of an update... got the 6 cavity Telewave duplexer tweaked up - looks like it pretty much hit the specs in the data sheet. With a dummy load at the 'antenna' port, I used an "iso-tee" to inject a signal at both the receiver input, and between the antenna port & the dummy load. With a weak signal, both places showed me that there was no desense. Very weak signal would hold in the repeater. However, putting the system on the antenna (a 150-160 mhz DB-224 100' horizontally & 10' vertically separated) through a metal building fed with 7/8 heliax, there seems to be no end to the desense! The wattmeter shows 30 watts forward & 3 watts reflected at the antenna port, if my math serves, it's less than 2:1. Can the less than 1:1 match be the culprit? Thanks, Tim W5FN