[Alastair, Aidan]

The Y-arm CO2 laser, which has not been getting injected to the CP, has now had its beam block removed so that we can perform the alignment proceedure.  The AOM drive from the DAC has a very low frequency pole that would stop us from injecting a large enough signal to do the alignment this way, so we have directly bypassed the module that has this filter.

Instead we put an oscillator directly on top of the enclosure set to 23.8Hz, 0.1V pk-pk, 0.1V offset.  This oscillator is running on AC power and has quite a noisy fan.  The oscillator is being fed through to the table and directly connected to the AOM driver, bypassing the DAC and all other electronics.

The laser has its rotation stage set to output the minimum power we could achieve (11mW) so this signal shouldn't be visible in the interferometer at the moment.  If it is critical to stop it doing this then the laser can be turned off from MEDM, however I would request that if at all possible we leave the laser running because I am still working on the long-term stability of the locking loops.