By all accounts, the Flagler 147.300 repeater has been sick forever – practically since the day it was installed (well over a year ago). But things are different now..!!  Initial coverage reports are excellent:

• Tim (WA3QCV) was on Old Dixie eastbound to A1A and going thru the canopy – full quieting thru the repeater and full-scale to his mobile. His comment, “147.300 coverage has NEVER been this good”,
• Doug (N4FPS) was on low-power in  St. Johns county on a J-pole (unity gain) at 25-feet with a full-quieting signal,
• Robbie was at home in Flagler Beach on 5-watts and full quieting.

A small team made the 2nd trip to the repeater site in Bunnell to do some troubleshooting, bringing not only test equipment, but also a:

• replacement repeater (Vertex VXR-7000)
• replacement duplexer (Tx/Rx Systems)
• intermod filter (DCI)

As you might remember, the first attempt at diagnosing the problem resulted in a determination that there was a STRONG signal at 148.220 coming from within the room (intermod). We knew that we could not possibly filter-out that signal, since it is so close to the receiver input at 147.900. After more digging, it appears as if the IF frequency of the VXR-9000 may have been contributing to the sensitivity at the intermod frequency. Further analysis on the bench indicated that the VXR-7000 model would be much less prone to the intermod products, so we programmed one of our spare VXR-7000′s for a test. We also tuned a spare Tx/Rx Systems duplexer for 147.300+ just in case there was a problem with the old duplexer (sometimes, they will cause intermod if they have been struck by lightning, even though they appear to be tuned properly (and ARE).

Our first replacement was of the repeater chassis with the VXR-7000 and Voila, everything worked like a champ (even though we re-used a horrible piece of RG-8A/U for the jumper from the receiver to the duplexer (not recommended since it has 95% shield, which allows 5% of the cable to “receive” the transmit signal and desense the receiver). But the test was successful, so we proceeded to optimize the jumpers and put the system back on the air.

Subsequent testing of the duplexer showed very good insertion VSWR, so all appears to be fine with the duplexer (since we retuned it last trip).

Coverage and S-meter readings in the field appear to be the same, whether operating in high-or-low power at the repeater, so we are currently operating at low power (about 26 watts).

This repeater is destined to be the Flagler A.R.E.S. repeater, since it is not club-affiliated and the callsign is coordinated to Bob Pickering of Flagler Emergency Services. It is also intended that Flagler Skywarn will also move to 147.300 when Robbie is ready to do so. Look forward to coming announcements as to the status and Nets scheduled on this repeater.

ML – 14-June-2010