Frequency Counter - Accuracy - HP 3457A Service Manual

Performance Tests
4-38. Frequency Counter - Accuracy Test
Frequency Counter Performance Tests Cont'd
3457A
4-39. Equipment Required. A Frequency Source capable of providing a 20 Hz (+ 016%) and a 1 MHz
(+ 003%) sine-wave signal is required for this procedure.
1. Set the HP 3457A to the Frequency Function (FREQ).
2. Set the Frequency Standard for a | volt, 20 Hz sine-wave output signal and connect it to the HI and
LO input terminals of the HP 3457A.
3. Use the Test Record to record the frequency readings at 20 Hz and | MHz.
4. If either of the readings are beyond the limits specified, the instrument should be calibrated or
repaired, Refer to Section V of this manual for calibration procedures,
Rear Input Performance Tests (Standard Instrument)
OSENSE (4 WIRE)
HI LO
HI
INPUT (2 WIRE)
0
450V pk
WAX
TO FRONT TERMINALS OR+
aii ty
©—a« CURRENT FUSE
REAR TERMINALS 450V pk MAX
3)
Figure 4-9. Standard Instrument Rear Input Performance Test Connections
4-40. Preliminary Steps
1, Short the Rear Input HI and LO terminals and the Q Sense HI and LO terminals as shown in
Figure 4-9,
2. Select the Rear Terminal Input. (Press the TERM configuration key, enter the number 2 and press
the ENT key.
4-41. DC Voltage Function - Rear Terminal Offset Test
4-42. Equipment Required. A low thermal short (copper re) is required for this procedure.
1. Set the HP 3457A to the DC Voltage function (DCV) and the number of digits displayed (DIGITS
DISP) to six.