Searching the website, I’ve just realized that I  haven’t written about the ARR Preamps I’ve added for VHF (2 meters) and UHF (70 centimeters). They arrived in the shack in January and April, respectively. With the initial installation I connected them directly to the back of the IC-910H transceiver. They do a good job of amplifying the weak received signal and they are set up to automatically switch out of the circuit when I transmit.

They are meant to be installed near the antenna, directly on the mast. This way they can grab the signal before it goes through all that coaxial cable and, as a result, drops its strength. With my set up, however, I have lightning arresters installed at the bottom of the mast that don’t allow DC power to travel along the coax all the way to the antenna to power the preamp.

preamps-1Recently my satellite elmer, Clayton, W5PFG, suggested that I mount the preamps somewhere along the coax to avoid overpowering the receiver. So, my weekend project was to mount them right by the lightning arresters. This gets them as close as possible to the antennas while still allowing them to be powered via DC on the coaxial cable.

You can get a glimpse of the installation in the nearby photo, note the nearby lightning arresters. I used a PVC pipe as the pretend mast, along with a couple of wooden shims to make everything work. I still need to make one of the connecting cables. I use Davis RF Bury Flex for most of my outdoor work. The needed cable is on the 2 meter side, which uses PL-259s from the receiver to the antenna, so  I’ve ordered some Amphenol PL-259s. Once that’s in place, I’ll do the tape wrap water-proofing.

Everything is working well on the satellites. I’m now thinking about ways to move the antennas from 10 degrees elevation and vertical polarization to zero elevation and horizontal polarization for the VHF-UHF contests. That’s perhaps the next project – needed in time for the January VHF contest.

Have fun in your ham radio adventures. I hope to work you on the air.


What do you think?