2013-03-08 Tried receiving PI3UTR on 2m and noted interference 6 years ago
I tried receiving PI3UTR on 145.625 MHz yesterday and noted serious QRM (man-made interference). Time to investigate the possible sources. One serious 'suspect' is the Devolo powerline setup which links the computer of the weatherstation in the shed to the network. In the plans for the future "sundial" weather station and time receiver that link will be replaced with a wifi link. Searching for 2m QRM also gives me linksys router interference to ham radio bands which suggests that the WAP54G access-point we use may also be a suspect. Time to get out the scanner with some 2meter frequencies programmed and search for the culprit. The linksys router interference article above has an explanation of the procedure:Here is a handy method of locating many noise sources on the HF/VHF ham bands. Using a 2 meter handheld, adjust it to an unused frequency. Leave the "Rubber Duckie" antenna attached. (Note that you may also use a portable shortwave receiver tuned to the respective hf band with an external "loop" probe setup as described below.) Stand back several feet from the suspected device or if needed in another room or location if the white noise "floor" is too strong. Adjust the squelch (on vhf transceivers) just to the point that the white noise stops if possible. If it does not, then you will have to remove the antenna and get much closer to the suspect device. On portable shortwave receivers without squelch, tune as needed for a "quiet" hf frequency in the band you have rfi on. Now move the handheld or portable receiver around or near each and every piece of equipment in your station that is near your router or associated cables. This includes it's power supply, wall wart, interconnecting cables, etc. If the squelch breaks and or noise poors from the receiver when you are very close, then you have pin pointed the suspect device! Now remove the antenna from the handheld remembering the device, cable, etc, that caused the squelch to break!Update:
At least it seems our cable provider Ziggo seems to keep the 2 meter band free. One less possible source.