Diamond SG7900 Dual Band Antenna

Two of my goodies from RARSFest was a Diamond SG7900 Dual Band Antenna and a Kenwood TM-V71A. I had been meaning to add 440 to my work truck for a while and looking for a way to crossband repeat to the JARS repeater from my home in Dunn. This radio/antenna combination did both. Although I’m happy with both purchases I’m very impressed with the performance I’m seeing from the Diamond SG7900. I had previously run a Yaesu 2900 75 Watt 2 Meter radio with a Larson 5/8 wave mag mount and I was concerned that dropping from 75 watts to 50 watts on 2 meters would decrease my range. I was wrong. The Diamond SG7900 with 50 watts input gave me about 30 miles MORE range than the 5/8 wave antenna did with 75 watts including a stationary contact on the 145.210 repeater from 85 miles away in Jacksonville, NC. The antenna specs back up my results with 5 dbi gain on 2 meters and 7.6 dbi on 440. The last piece of equipment in any system can make or break the performance of the whole system and in ham radio that’s the antenna. High end stereo equipment is similar. A premium system feeding rotten speakers will sound rotten. A premium radio feeding a poor antenna will perform poorly. Ask the QRP folks who work the world on 1/2 watt! You can bet they have a good resonant antenna. One down side to the SG7900 compared to the Larson 5/8 is size. The SG7900 is 62″ tall and is not very flexible. Also, it is not recommended for a mag mount. I have been running it on a mag mount but it did blow over at about 75 mph on a gusty day. Calm air at my ‘normal’ highway speed has been fine but I do intend to go to a bigger mount. It does have a foldover built in for when you think ahead before going into the garage.
The Kenwood TM-V71A is very nice too. It has a dual color green/amber display, the control panel can be flipped for speaker on top or bottom or remoted. It’s great for crossband repeat into the repeater AND (this is really cool) has a power off timer so no dead battery on Monday morning. That’s all for now, I hope my experience with this radio/antenna combination helps someone out there. 73 de KS4TI

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