Yes, that was essentially what I was seeing over a few runs. The failure times I saw were on the order of 2-4 hours. I've moved my 5370 over to a UPS, along with the Prologix and the router, and I'll see what happens. I have to wait until my 3-day 5334 run finishes, though. I'm measuring long-term phase difference between my 5061A and my Z3801A. The 5334 has been running solidly for 1.5 days, so I can eliminate power problems at this point. This brings up another question. I'm seeing cyclic phase variations of about 10 ns with a pretty regular 1 hour cycle. The overall long-term average is OK, 1e-13 ADEV at 6000 seconds. I'm guessing this has something to do with satellite orbits, but I'd welcome any explanations. As for the 5370A bug, there was a thread a while back in time-nuts describing a bug in the GPIB controllers for the 5370A's that would occasionally and randomly cause a bus lockup. This problem was supposedly fixed in the B series. That's all I've seen on the issue, so it's possible that the bug doesn't actually exist. If I still get failures, I'll swap in a controller from my spare 5370 and see if there's any difference. BTW, I've been doing precision AC and DC measurements for a long time, but I have to say that high-resolution time/freq measurements are even more fun! Bill Ezell ---------- They said 'Windows or better' so I used Linux.
John Miles wrote: I'm not familiar with any GPIB bugs on the 5370A, but I moved your code over to C and ran it on my 5370B via a GPIB-LAN adapter. The test app failed after ~6 hours with a Winsock timeout error. I'm thinking that was caused by a power glitch, though, because I actually had to power-cycle the counter (rather than the Prologix dongle) to get the program running again. Was that your experience? Since then it's finished a 24-hour run without any sign of trouble. -- john, KE5FX If the 5370A problem is actually the 5370A gpib controller bug, then I don't think it can be reproduced with the 5370B; I'm pretty sure that was fixed in the B model. However, if you want to give it a try, here's what I do (you'll have to interpret, but it should be pretty clear)... C version: GPIB_connect(atoi(argv[1]), GPIB_error, 0, 20000); // Set 20-second timeout GPIB_set_EOS_mode(10); GPIB_set_serial_read_dropout(20000); // 20-second dropout GPIB_write("SS2"); // Sample size = 100 GPIB_write("MD2"); // Lock out rate control, hold until MR GPIB_write("AR1"); // +T.I. arming only Sleep(2000); GPIB_write("MR"); // Manual read (discard first reading) Sleep(1000); for (S32 h=0; h < 24; h++) { for (S32 m=0; m < 60; m++) { for (S32 s=0; s < 60; s++) { GPIB_write("MR"); Sleep(1000); printf("%d:%d:%d %s", h,m,s, GPIB_read_ASC()); } } } _______________________________________________ time-nuts mailing list -- [EMAIL PROTECTED] To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. References 1. mailto:time-nuts@febo.com 2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ 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.