Jeff, Sheila, Fil, Elenna, Oli

The feedthrough cables (air side) for MC2 M2 and M3 have been swapped and now MC2 is back to behaving how we expect it to. Transfer functions for M1 to M1, M2 to M2, and M3 to M3 are correct (red traces) and crossover plots for MCL and M2/M3 are looking good.
Current correct cable numbering for MC2 at the HAM3 D6 feedthrough port is:
D6-F1 -> MC2 M3 (HAM3_020)
D6-F2 -> MC2 M1 (HAM3_001)
D6-F3 -> MC2 M2 (HAM3_019)
This should be updated in the flange layout D1002874, which I don't see the altium file for. Next time we open up HAM3, we should fix this lineup so F1/F2/F3 line up with MC2 M1/M2/M3.

Full troubleshooting:
After lots of troubleshooting and my MC2 M2 and M3 measurements from yesterday, Jeff noted that the M2 to M2 TFs looked a lot like the M3 to M3 Tfs, and vice versa. This was also very suspicious because back in May (90185) there had been a feedthrough swap for the feedthrough that MC2's M1 (T1/T2/T3/LF), M2, and M3 were all connected to, and M1 and (we thought) M2 had been found to be plugged in incorrectly on the vac side. After the plugs going into F1 and F2 had been swapped, we had measured only M1 to confirm that the swap was successful.

A (silly) mistake:
Fil and I went out to HAM3 D6 flange and meant to swap the M2 and M3 cables, but since the flange layout was still listing F1 -> M1, F2 -> M2, F3 -> M3, we swapped the cables connected to F2 and F3, which were actually M1 and M3, respectively. We determined that this was wrong because M1 to M1 and M3 to M3 looked horrible but M2 to M2 looked the same as before (wrong but not different), which means that M2 must have been in the F1 port and so hadn't actually been swapped with M3. We noticed later that this lineup was written in the May 8th MC2 'fix' alog(90185).

Actual fix:
We plugged M3 (HAM3_020) into F1, M1 (HAM3_001) into F2, and M2 (HAM3_019) into F3. Here's a diagram/timeline of this mistake and fixing it.
Everything is looking good for MC2 and it seems like we've been able to go back to using MC2 to lock the IMC normally.

I'll add plots next week comparing MC2 M2 to SRM M3 and vice versa