This morning while arriving at ISS1 site to check on the systems, RASS was running but I automatically noticed that it did not sound "normal." I walked around the enclosure to get a better listen to the speakers and I feel that I heard at least 2 of them have a crunchy static noise. The speakers I thought I heard doing this (if going clockwise starting at the surround closest to the gate) was the 2nd and 4th speakers. At around 0910 I turned off the system and set the software config to only run RASS. I then unplugged all but one speaker to start troubleshooting this sound. The speaker I started with was #2. When I turned it on it sounded pretty normal, even though I thought this was possibly a bad one. Next I tried speaker #3. It seemed that I was hearing a noise caused by vibration. I did notice the speaker was moving around a bit when messing with the plug and that a nut had come off of one of the rods, and I had placed the bucket on the ground next to the surround. I tightened up everything and moved the bucket away, and the noise I was hearing seemed to not be noticeable anymore. When I went to try the speaker #4 instantly I heard the crunchy static noise and it went on for a little while but then seemed to fade. I had planned to change this speaker, after checking the last one. Speaker #1 did the same but the static cleared pretty quick. I restarted the software and then the static did not come back. I retested speaker #3 to see if the speaker was for sure bad and the static was not there. This static seems to be intermittent, or maybe went away after re-seating all the plugs. I decided to plug in all the speakers and take another listen and it sounded normal again and no static was present. I held off on replacing any speakers since this is intermittent at the moment. Either re-seating the plugs helped or it is a little colder this morning, and possibly that could be affecting the speakers? If we do end up having two bad speakers we do have two spares in the trailer. I will keep monitoring the speakers a little more closely due to this. I reconfigured the software to how it was before and restarted the system at 1015.
Bill let me know if you are seeing anything in the data that would constitute changing any speakers sooner.
2 Comments
Elizabeth Bernhardt AUTHOR
1/24: Listened to speakers at 0930 and 1230 today so far and everything sounds normal
William Brown
Thanks for working on the RASS speakers Liz, I think that helped. I've been checking the RASS data and it is working well, typically giving virtual temperatures up to the 1.2 - 1.5 km range. I did modify the analysis procedure a little to cut down on invalid points, but that wasn't related to the problem that Liz fixed.