Impedance is impedance. The MFJ analyzer should be as accurate for that antenna as any other.
However, the analyzer's signal is very small, and at any site where other transmitters are nearby, the analyzer's internal SWR bridge can be fooled by signals other than its own, leading to erroneous readings. You may need to use an external SWR bridge or directional wattmeter and run some significant power to get an accurate reading. That said, your symptoms suggest you have a real problem, possibly with the feedline, inter-element harness, or a connector. 73, Paul, AE4KR ----- Original Message ----- From: Ian Miller To: Repeater-Builder@yahoogroups.com Sent: Friday, September 05, 2008 7:43 AM Subject: [Repeater-Builder] Antenna question Our group has a Sinclair 8 dipole array for UHF. The repeater was recently moved, and has not been behaving as usual. It hears OK, but seems weak on transmit. One of the members went up to the site last night with an MFJ antenna analyser - and he measured SWR at 3:1 - with no real resonant point. Our old UHF beam that was on the same tower and same feedline had an SWR of 1.5:1 measured on the same analyser. Is this method of measurement on an 8 dipole antenna correct? We have not put an SWR bridge on it. For the moment the repeater is off the air until the antenna question is resolved. What is inside the guts of one of those 8-bay antennas? Do they have a weak point where a bad connection can occur? Thanks Ian VA2IR
