This is probably for the radio amateurs out there…
I’ve recently installed a 2m/70cm vertical antenna fairly close to my Davis ISS (50cm away). I’m only transmitting up to 10W on either band but I was wondering if anyone has had experience of doing this and did you see any RF issues in the ISS?
I’m also going to install a multi-band HF vertical antenna fairly close to the ISS. This will mostly be used for 40-10m operation with fairly low power, e.g. 10-20W, but on occasion I might run up to 100W. Has anyone seen ISS problems caused by HF up to 100W?
It probably depends if there are any dry/rectifying joints in the ISS or anemo cabling. . .
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The frequencies are far enough apart that it shouldn’t cause any issues, although 50cm isn’t very much distance.
I’m assuming the antennas are well above the ISS and it’s not horizontal to the top of the 2m & 70cm antennas, which is where most of the RF will be emitted from.
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The bottom of the VHF/UHF antenna is about 50cm above the top of the ISS.
The ISS is mounted on one side of a 100*100mm wooden post that’s concreted into the ground. The VHF/UHF antenna is mounted on a metal post attached to the other side of the wooden post. I’m thinking of mounting the HF antenna onto another side of the wooden post. It needs to be mounted about 1m above ground level so the radiating part of the antenna will be relatively close to the ISS.
I may still find another place for the HF antenna though. I’m just considering options at the moment.
Given the frequencies and power level i’d be surprised to see any interference. I used to be able to drive my GW1000 nuts by aiming my beam at it and running 1500 watts on 24.9 MHz (12 meters). Adding a toroid to the sensor wire elimintated it.
Jim
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Now that it’s sunny again rather than grey, gloomy and rainy, I can see the intended site better!
The base of the VHF/UHF vertical is actually about 1m diagonally above the ISS main board. The anemometer is actually mounted on another transmitter about 15m away so there aren’t any long cables associated with the ISS that could pickup signals.
Also, now that I look more closely the wooden post probably isn’t going to be a good site for the HF antenna. I’m in discussions with the Head Gardener about other potential locations. Not that we’ve got loads of options in a fairly small garden that already has lots of trees and other tall-ish structures in it!