The pumping station is located in the Mechanical Room, the vacuum line in question starts there at a temporary pumping station, then penetrates through the wall, into the LVEA, approximately between HAM5 and HAM6. Then it joins the direction of the main tubes, turns north, and then turns east at BSC2, and runs a little bit over BSC7. The purpose of this noise examination is to justify if we can pump this line during observation. It would be quite advantageous, as this is crucial for the cleaning attempt of this line, after the Hepta incident.
On this pumping cart we have a Turbo and a backing pump. The backing pump definitely the noisier, it runs at 1660 rpm = 27.67 Hz. The Turbo pump runs at 60000 rpm = 1000 Hz.

During the measurement, the pumping cart was switched on and off, and the changes in the operation of the pumps have been noted. Beforehand, a loud noise was generated on the tubing, by hitting it with a wrench. The noise measurement, in time:
13:02 - gate valve was closed - some minimal noise: the pumping cart was on at the beginning of the measurement
13:04 - 13:05: hitting the tube with a wrench, approx 2 Hz: quite some noise
13:05 - gate valve reopened - some minimal noise (the reason behind the opening/closing of the gate valve is non-related to the noise-experiment, it is only VAC-related)

13:06:42 - press STOP - this has nothing to do with the noise
13:10:20 - backing pump stops: 27.67 Hz noise-source disappeared. Also, Turbo pump's freq was changed to 850 Hz
13:11:50 - Turbo pump's freq. was changed to 775 Hz
13:13:05 - Turbo pump's freq. was changed to 700 Hz
13:13:20 - Press ON: backing pump starts - 27.67 Hz noise source reappears
13:15:05 - Turbo pump is at full speed: 1000 Hz

13:18:00 - press STOP - this has nothing to do with the noise (1E-4 Torr)
13:21:38 - backing pump stops: 27.67 Hz noise-source disappeared. Also, Turbo pump's freq was changed to 850 Hz
13:23:00 - Turbo pump's freq. was changed to 775 Hz
13:24:15 - Turbo pump's freq. was changed to 700 Hz
13:25:00 - Press ON: backing pump starts - 27.67 Hz noise source reappears
13:26:50 - Turbo pump is at full speed: 1000 Hz

13:29:55 - press STOP - this has nothing to do with the noise (1E-4 Torr)
13:33:30 - backing pump stops: 27.67 Hz noise-source disappeared. Also, Turbo pump's freq was changed to 850 Hz
13:34:55 - Turbo pump's freq. was changed to 775 Hz
13:36:10 - Turbo pump's freq. was changed to 700 Hz

13:36:35 - gate valve was closed (8.5E-2 Torr)