No announcement yet.

Avoiding Long Coax Runs

  • Filter
  • Time
  • Show
Clear All
new posts

    Avoiding Long Coax Runs

    To escape the noise field, and avoid angering the HOA, my VHF antennas are located at the far end of my back yard. It's roughly a 200 foot run back to the shack. I'm using RG-11 cable to reduce losses, but have been thinking that it might make more sense to mount an AirSpy HF+ Discovery in a weatherproof enclosure near the antenna.

    A couple of options come to mind. Inexpensive USB over ethernet extenders are available that allow you to use outdoor CAT6A ethernet cable to control USB devices at a distance of close to 200 feet. That might work. My nearest antenna is a four-element NOAA Weather Radio Yagi at 75 feet. I plan to test the idea using that antenna first.

    The other option is to try to remotely control SDR Sharp by placing a PC in the shed on the far end of my yard. I'm sort-of doing that now with my FM6 Meteor Scatter antenna. I have a laptop in the shed that is running SDR Sharp in "autologger" mode 24/7. It works great and has only a 25 foot coax run into the shed. But I haven't tried controlling the software remotely.

    Does anyone have experience in this area? Looking for ideas.

    I'm not crazy about the idea of running usb over ethernet cable at 200 feet. I suspect you will lose a lot of noise immunity plus experience some voltage drop which will further worsen the noise immunity.

    What I would suggest is to put a raspberry pi (or equivalent) in your shed and have a short run of usb cable to your Airspy. On the raspbery pi, run some sort of WebSDR software. Connect the raspberry pi back to your house via ethernet cable. Or, get a pair of wireless devices like Ubiquity or Mikrotik to bridge your 200 ft separation. And, since you are a ham, flash those devices with AREDN firmware and build yourself a wireless network on frequencies in the ham bands away from the rampant Part 15 QRM.


    73, Mark, N2MH


      Mark, Thanks for suggesting these possibilities. I'm familiar with mesh networks having used them for emergency communication deployments on the ham bands during hurricane response. I'm a bit embarrassed to say that I have never done the first Raspberry PI project, so I need to look into that. Anything to avoid the signal loss. Even with RG-11, it's not trivial.

      This will likely be a project for late summer, after the season ends. Thanks so much for responding.


        Airspy does have a version of their SpyServer software that will allow you to put that Airspy on a RPi and then connect to it remote from inside your long as you can get Ethernet to the RPi device.

        That is what I am going to be doing soon to get my old HF+ Dual running with my Grove Scantenna that is up in the attic.