Hi Since we have moved into synchronizing this stuff at the nanosecond level (maybe we are even lower than that by now ..), simply getting a wide band enough signal off of a Nixe socket is going to be “interesting”. An array of picosecond photo diodes on each tube may be the only way to go. How many channels this all will take depends a bit on how many digits past the second the display will show. Is it 9 digits past the second?
Since you will only know the ignition point *after* it has happened, the system only works to a certain degree. Trigger point *is* dependent on the light level. You will need to collect real time data to keep things consistent. Bob > On Jul 16, 2016, at 10:49 AM, David <davidwh...@gmail.com> wrote: > > Use AC coupling to each digit to measure the ignition waveform and > detect the breakdown point like with a tunnel diode trigger. Use a > higher compliance voltage and greater negative resistance (constant > current drive?) to lower breakdown jitter. > > On Sat, 16 Jul 2016 00:08:45 -0700, you wrote: > >> Yes, I was planning on using a high speed photo diode to actually >> measure the turn on time of the digits. I hadn't thought of the turn OFF >> time, do I want the old digit to be turned off before the new one lights >> up or for them to be overlapping? I have been thinking about what >> threshold to use, 50% intensity is probably about as good as any other. >> It might turn out that different digits turn on differently, so I will >> have to calibrate each one separately. >> >> John S. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
