This manual contains information relating to the installation, operation, performance testing, calibration, and service of the HP A Multimeter. The information. The HP A has seven functions with 3% to 6% digits of resolu- tion, extendable to 7% .. (). Opt Extra Operating and Service Manual. +$ Hp A Pdf User Manuals. View online or download Hp A Operating Instructions Manual, Service Manual.
|Country:||Sao Tome and Principe|
|Published (Last):||3 March 2008|
|PDF File Size:||9.68 Mb|
|ePub File Size:||19.19 Mb|
|Price:||Free* [*Free Regsitration Required]|
Much more important fact is, that display is now visible and usable at night time. Sounds too good to be true?
LED mount for display backlight. So in next chapter we will try some ,anual for first four circuits. R trimpot adjutment for offset correction.
A Digital Multimeter [Obsolete] | Keysight (formerly Agilent’s Electronic Measurement)
Carefully lift rear side of the shield, disconnect cable from rear terminal and turn screen up. Different non-modified HP A performance test, as returned after calibration adjustment, 4-wire resistance. Well, in analog design world things are much more complicated, and swapping components without understanding what the circuit do is a road to a disaster and broken equipment. Also each function and mode can be configured either from front panel or remotely over GPIB interface.
Check the table below with uncertainty calculations. Redistributions of article must retain the above copyright notice, this list of conditions, link to this page https: Digital a 1 Assembly Renioval Diodes in drain circuits create virtual gaps to allow current tapping by DMM s. Outguard earth-referenced domain contains of: HP A overview Image 2: HP A can also use optional expansion card with multiplexer scanner, to add up to 10 channels for input signals.
Backlight boards with LED diodes installed on mount frame to position light for the edge of display maanual. I tried to combine modifications in groups, so can test multiple things at same time, when that was possible.
File:HP A operating – Hive13 Wiki
Basic DCV accuracy is specified better than 5 ppm. So main interest go to other possible noise sources.
So I got idea to prevent running this procedure for intermediate testing. Details and modifications were tested on actual single HP A unit, and may or may not work in your particular instrument.
Worth to note, that this operational amplifier must be stable with both high and low gains, and as we will see later, most troublesome range for stability is 3 V. This opamp provide most of the gain. Everything else, like charge rate switches, counters and control logic integrated on U hybrid ASICor hp4357a auxilary roles reset comparator Ua, switches.
File:HP 3457A operating manual.pdf
LT circuitry near DCV reference. Instahation Of Options Higher voltage ranges are even trickier.
Dc Volts Offset Calibration Suspects are listed below: Recommended Test Equipment Likely, largest contributors to noise performance are C Q U U Now we have just two more things to do. Even with shorted input, when reference noise irrelevant to ADC! Ac Convertor Frequency Response Adjustment Current-limiting resistors are mounted on additional board for the board with four LED s. On ranges 30 mV, mV and 3 V amplifier gain later A is Replacement Q matching One kind person my kind regards presented me with thin copper foil with adhesive layer.
Linear power regulator and optoisolation interface between the domains. Upgrades and modifications on this HP A were attempted for long time, multiple times for period over a year. And calibration of that meter is very expensive, to let such mistakes pass by. Also calibration commands protected by password, which can be configured by user following special procedure. In service manual this procedure was explained for only case when self-test diagnistics related to this section unable to pass.
HP A input amplifier after all modifications Image These auxiliary circuits do not affect noise performance of the ADC.