JOHN Fluke Mfg. Co., Inc.
845AB High Impedence Voltmeter Null Detector
Serial Number: 3100019
Input Voltage Range: 1microvolt to 1000 volt dc end scale in nineteen ranges, using X1 and X3 progression.
Input Resistance: 100 megohms on 300 millivolt range and above.
10 megohms on 100 millivolt range and above.
Accuracy: +/- 2% end scale + 0.1 microvolt.
Input Isolation: Better than 10 to the 12th ohms
DC Common Mode Rejection: Better than 160 db.
AC Common Mode Rejection: 100 volts rms or 120 db greater than end scale, whichever is less.
AC Normal Mode Rejection: ( 60 Hz and above ) AC voltages 60 db above end scale will effect reading less than 2% of end scale.
Recorder Output: 0-1 volt, one side at chassis ground; to 0.5% of end scale.
Output can be operated as a dc amplifier with a maximum gain of 120 db.
Stability of Zero: Better than 0.15 microvolt/hour.
Better than 0.3 microvolt/day.
Temperature Coefficient of Zero: Less than 0.1 microvolt/degree C from 15 C to 35 C.
Zero Control Range: +/- 5 microvolt minimum.
Overload Protection: Up to 1100 volts dc may be applied on any range.
Typical recovery time is 4 seconds.
Input Power: Rechargeable battery or 115/230 volts ac +/- 10%, 50 to 440 Hz.
40 hours operation on full charge, trickle charge on line power.
Weight: 10 ?pounds
Size: 8 inches high by 8 ?inches wide by 9 inches deep.
Full Instruction, parts, operation, theory, and calibration manual included.
No other accessories are supplied by the manufacturer for this meter.
NOTE: This unit is considered a Primary Standards Laboratory grade Electronic Instrument.
Unit sold new for $2,500.00 US, is over 10 years old, presently in near New condition.
Last calibrated 1998 - NBS, Fort Collins, Colorado.
Will sell for $750.00 US. Any reasonable offer will be considered.
I am located in Houston, Texas. E-mail: firstname.lastname@example.org