2012/04/28

1800	Fill N2 cold trap full.
2100	Although striking needle valve with Allen key does induce significant microphonics, attempting to hit it at a rate of 1, 2 or 4 Hz does yields PSDs similar to those from the 20 cm drop test. Data not taken.

Retaking PSDs

Due to relatively low level of microphonics induced in Qi vacuum channel on 2012/04/23, PSDs for the following DCRC configurations were retaken:

PSDs were generally noisier than those that had been taken on 2012/04/23. Unusually, Qi vacuum is noisier than Qo vacuum.

Figure 1: DCRC32 attached to flexible side coax, DCRC33 connected to vacuum side coax.

Figure 2: DCRC33 connected to both side coaxes.