| Electronics > Repair |
| Fluke PM6666 counter freezing after 3 seconds from turning on. |
| << < (14/27) > >> |
| pizzigri:
Thinkfat, I did as suggested! Yes, that is exactly what happens. I started the meter with the GPIB board connected and waited until the thing locked up. Then, i disconnected the SDA line, still locked up. Then the SCL, and it unlocked, all this obviously with the meter powered. I am looking at the manual excerpts that FransW is posting, and the "Addr 10" is indeed the GPIB... |
| thinkfat:
What I can see is that the OCR didn't really increase the utility of the scanned document :-) |
| pizzigri:
Yes, haha! In any case better than nothing at all... In the meantime I connected my scope and got a 5mhz signal, quite jittery but that could be imperfect probe technique. |
| pizzigri:
Going to say something really stupid here but... could it be a ground related issue? I see dispersion on the chassis, and the oooold Schaffner filter is still in place - the ones that exploded... Suggestions? |
| thinkfat:
Ground is probably not a major issue, but the 5 MHz signal doesn't look too good. Does the documentation say anything about it? 2.54V peak is too low for a CMOS input (which I assume IC2 has). A CMOS logic high level starts at 3.5V. For TTL it would be OK. Is there anything specified about maximum rise time? EDIT: I saw you use a 1X probe. That might get you into a bandwidth issue. Switch the probe to 10X and make sure it's properly compensated. Then redo the measurement. |
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