Re: 485 super weak brightness control


Ozan
 

I measured A sweep A Gate B sweep B gate

In the long times all the A sweep A gate and B gate are exactly the same
length and correct but there is no B sweep at all.
What is the B sweep voltage level when there is no sweep?


As the things go to the ns range the zeroed B offset starts to show so it's
slightly delayed but more importantly the B sweep at one point doubles on
its amplitude and starts having a flat top (saturation) from then on its
Both A and B sweep are expected to reset to +13V and should go down from that level when gate starts. When you say it doubles does it always start from +13V but end at different voltages (i.e. delta-V is double) or does the top start from a different voltage? Top should be flat if you are looking at sheet <11> (there is inversion if you are looking at A-sweep at the BNC, then bottom should be flat).

I'm wondering if its best to wait for the relays and continue
troubleshooting after that it if there is something we can tackle in the
meantime while I source needed parts
Please see my earlier comments about the relays, did you test them off the board? The relays are supposed to be off until timebase > 200ns, you can pull them off and debug 1ns-100ns range. However, it is up to you if you want take a break and work on something else.

Ozan

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