Showing posts with label beam stabilization. Show all posts
Showing posts with label beam stabilization. Show all posts

Thursday, November 30, 2006

Timing delay jitter problem

Unfortunately, we could not resynchronize the TWINAMP using the two separated trigger pulses. I think the large RMS jitter from BNC 7010 digital delay generator makes the synchronization failure. So I replaced the BNC generator with SRS DG-535, the TWINAMP ran steadily. DG-535 has only 50 picosecond RMS jitter. The best way to eliminate this jitter is to control 4 channels of DG-535 by computer. If we buy a GPIB-RS232 converter from NI, it's easy to communicate with only one DG-535 for switching on or off the trigger signals("out 1" and "sync out").

Monday, November 27, 2006

New timing setup for beam stabilization system

The beam stabilization system needs control signals from SDG II "out 1" and "sync out", so I have to change the timing again. I already modified the timing for the front end before (on July 7th), but I did not consider to trigger the Pockcel and TWIN AMP separately. Now I have to insert one more delay box such as BNC delay generator in order to trigger the TWIN AMP.

The beam stabilization system includes one CCD camera and one chopper, both of them also need the TTL pulses to trigger. The pulses from BNC #1 to trigger CCD, #2 to trigger the beam chopper.