kiwamu.izumi@LIGO.ORG - posted 21:14, Thursday 04 September 2014 - last comment - 09:38, Friday 05 September 2014(13766)
bad SMA connector in ASAIR LO path, currently disconnected
Wiggling some RF cables for the ASAIR_A_RF45 demodulation, I found a bad SMA connector that was for the LO signal at the fied rack. Depending on stress on the connector, it could rotate the phase by about 90 deg. I attempted to fix it, but I could not find the crimping tool kit in the EE lab. We will do it tomorrow once the tools are found. The RF cable is currently disconnected.
Fil fixed the cable in this morning and therefore I went ahead and installed the cable back. As far as I tested by applying some stress on the SMA connector, the funny phase jump seemed to have disappeared. Hopefully this will fix the RF phase issue.