Hi In an earlier thread on the 5370B checking the voltage out of the regulators was mentioned. If you are going to open the counter up anyway, putting a DVM on them is probably a good idea. They do run hot and some eventually drift way out of spec. Cheap part to replace if it's bad..
Bob On Sep 14, 2010, at 3:12 AM, "Charles P. Steinmetz" <[email protected]> wrote: > A friend just received an HP 5370B that was said to be properly working and > accurate, and asked my opinion. I'm not familiar with these, so I thought > I'd ask the experts. All we've done so far is hook it to a Tbolt that I know > is operating properly. > > The 5370B took hours (8 or so, which seems like a long time for a 10811) to > drift to a reasonably stable reading, a bit over 100 Hz high (which seems > like an awful lot for a 10811, even after a trip across the country ten years > since its last calibration). The front-panel oven indicator is off; I did > not notice if it was on when we first powered it up. The 5370B reads its own > oscillator within spec (< 2 mHz error; spec is +/-5 mHz). We have not opened > it to tweak the oscillator (or to verify that the 10811 is, in fact, still > present). > > Timing seems to work OK, giving the expected 100 nS and 50 nS figures when I > feed the internal oscillator into the start input, tie start to stop (START > COM), and switch the trigger phase of the stop channel. > > Finally, the external heatsink (left rear) runs pretty darn hot -- somewhat > warmer than you'd really like to leave your hand on, which is WAY warmer than > I'd ever design. Concerning (to me), but not completely beyond reason. I > suppose it could be normal for these. It didn't burn down or shut off during > the 8 hour warmup. > > I appreciate any input from those knowledgeable about the 5370B. > > Thank you, > > Charles > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
