The interference you hear is due to APRS on Mt Richmond getting into the Portland repeater due to overload on the site.
Peter has tuned up a notch cavity and a bandpass cavity but due to the Hill Climb responsibilities we can’t do anything about it for a week or two. I’ve also modified a new board for the CTCSS to install when we go over there.
Here is a note I put on the Portland Facebook page.
We’re having trouble with the APRS getting into VK3RSW 2M repeater. This afternoon we’ll turn off the link to the rest of the system as it’s making the system over here unusable. We’re flat out with the hill climb at present so it may be a couple of weeks before we can get over there to put an extra filter in. We’ll also set up VK3RSW for the standard 91.5Hz tone access. At present a tone is not setup properly. We have a cavity filter tuned up for the receiver to try to overcome the overload situation, hopefully this will be all that is required. Another technical difficulty is that the APRS is radiating a 91.5Hz tone and this may make setting the tone on as an added precaution ineffective. If VK3 users would rather, we can turn off Mt Richmond altogether until we get over there. I’d appreciate your advice. For the Sunday broadcast we will turn on the link so people can hear the broadcast. The joys of setting up a new repeater, but I’m sure we’ll get there. Thanks for your patience.