New Antenna, Strong Results: GSARA Repeater Gets an Upgrade
On Tuesday, August 4, the GSARA repeater received an important upgrade with the installation of a brand-new antenna.
Paul, KA1PAT, joined Tom and Tom’s son-in-law at the repeater site around 5:00 p.m. With the weekly net approaching, the team had a clear deadline: complete the work, test the system, and have everything operational before net time. By 6:45 p.m., the tower was back up, the repeater was online, and AA1TX was able to conduct the net as scheduled.
Fortunately, Tom had already completed much of the preparation work around the equipment hut. The team disconnected the antenna coax from the radio and duplexer equipment, then pulled it outside so it would remain safely out of the way while the tower was lowered.
With the tower tilted down and accessible, Tom reworked a connection for another antenna mounted on the structure. Meanwhile, Paul and Tom’s son-in-law removed the old repeater antenna and installed its replacement.
The new antenna was secured to the mast using high-quality mounting hardware. The N-type coax connection was also carefully weatherproofed using a three-layer method: electrical tape first, sealing tape second, and another layer of electrical tape on the outside. This provides strong protection from the elements while still allowing the connection to be removed more easily during future maintenance.
The team also replaced the existing tie wraps with larger, stronger ones and added several additional tie wraps to keep the coax and antenna assembly secure. Once everything was inspected, the tower and the entire antenna assembly were carefully raised back into position without any problems.
Excellent Test Results
Before the tower was raised, the team measured the antenna’s standing wave ratio, or SWR. Additional measurements were taken once the tower was back in position, both before and after the repeater equipment was connected.
At the repeater input, before connecting the duplexer cans, the system measured approximately:
1.0 to 1.1 SWR at 146.085 MHz
Approximately 1.2 SWR at 146.685 MHz
Once the antenna was connected through the duplexers and into the repeater equipment, the complete system measured approximately 1.5 SWR.
Tom noted that the duplexers naturally introduce a small amount of loss into the system, but the final measurements were still considered very good.
This successful antenna replacement is another example of the behind-the-scenes work required to keep the GSARA repeater operating reliably. Thank you to Tom, his son-in-law, and Paul, KA1PAT, for contributing their time, technical knowledge, and hands-on effort to get the project completed safely—and just in time for the net!
