TB 9-6625-102-24
Table 14. Square Wave Output.
TI
Frequency Counter
Freq Out (Hz)
Duty Cycle
Measurement Type
Min
Max
120
50
Freq
119.9740 Hz
120.0260 Hz
4800
50
Freq
4799.74 Hz
4800.26 Hz
100
50
Duty
0.498010
0.501990
100
25
Duty
0.249005
0.250995
100
75
Duty
0.747015
0.752985
(6) Disconnect frequency counter from TI and connect digital multimeter INPUT HI
and LO to TI A mA CHG
and COM inputs.
(7) Set digital multimeter to measure V dc.
(8) Configure the TI for a 4800 Hz 99.609% duty cycle.
(9) Digital multimeter will indicate between 2.6 and 3.0 V perform b below.
(10) Disconnect equipment setup.
b. Adjustments. Perform entire calibration procedure before performing alignment
procedure listed in paragraph 17.
17. Alignment
NOTE
Specifications are only guaranteed within the period stated
from the last adjustment. Agilent recommends that complete
re-adjustment should always be performed at the calibration
interval. This will assure that the U1252A will remain within
the specifications for the next calibration interval.
NOTE
Allow a warm-up period of five minutes with a Shorting Plug
connected to the V and COM input terminals.
a. Unsecuring TI for Alignment
(1) Set rotary switch to
V.
(2) Press and hold the SHIFT and Hz keys simultaneously to enter the Calibration
Security Code entry mode.
(3) Enter the security code 1234 using the ◄RANGE and ►DUAL keys to select
the primary display segment to be edited and the ▲HOLD and ▼NULL keys to select the
desired digits.
(4) Press the Hz key to save when done.
(5) If the security code does not work, refer to manufacturer's manual for unsecuring
the instrument without the security code.
(6) Skip to paragraph c below.