Model 122A/AR Section V
Paragraphs 5- 1 to 5- 11
SECTION V
MAINTENANCE
5-1. INTRODUCTION. Amplifier adjustment procedures, Paragraph 5-30,
before proceeding further.
5-2. This section contains the performance check,
Paragraph 5-5, adjustment procedures, Paragraph c. Check dc response by switching a 0.1 volt dc
5-2 1. Schematic diagrams, troubleshooting infor- levelfromthecalibrator off and on. As the voltage is
mation, and Component Identification are in Section switched off and on, the CRT spot should shift 10 cm
VIII. *3%, Adjust VERTICAL POSITION as necessary.
d. Check the accuracy of the remaining positions
5-3. TEST EQUIPMENT.
of the attenuator. Table 5-2 lists the selector switch
5-4. Test equipment required for maintaining and positions and gives the peak and rms voltage which
checking the performance of the Model 122A/AR is should produce the deflection listed.
listedin Table 5- 1. Test equipment having character-
istics similar to those listed in the table may be sub- Table 5-2. Vertical Deflection Sensitivity
stituted for the performance check and adjustments.
Sensitivity Deflection Voltage Required
5-5. PERFORMANCE CHECK. Volts/cm cm *3%
Pk-Pk rm s
5-6. The performance check verifies whether or not 0.01 5 0.05 0.01767
the Model 122A/AR is operating within the specifica- 0. 1 5 0. 5 0.1767
tions outlined in Table 1-1. This check may be used 1 5 5.0 1.767
as part of an incoming quality control inspection, as 10 5 50. 0 17.67
a periodic operational check, or after repairs and/or
adjustments have been made. Recently calibrated test e. Repeat steps c and d using the ac ranges.
equipment should be usedwhen performing this check f. Repeat above procedure for channel B.
If the instrument fails to meet a specification, care-
fully recheck instrument setup and the procedure; then )
if necessary, refer to the troubleshooting paragraphs 5- 10. VERTICAL AMPLIFIERBANDWIDTH. AWide
Range Oscillator (such as hp Model 200CD) and a
or adjustment procedures. Refer to Section I1 for Vacuum Tube Voltmeter (such as hp Model 400H) are
warranty and claims information. The performance required for this check.
check should be completed in the sequence given below.
Do not attempt to start the procedure in mid-sequence, a. Set the Model 122A/AR controls:
as succeeding steps are dependent upon control settings
VERT PRESENTATION - * * * * * * * * * *A
and results of previous steps. A VERT SENSITIVITY - - .01 VOLTS/CM
TRIGGERLEVEL. - * 0 0 - * * * - AUTO
5-7. VERTICAL AMPLIFIER. b. Connect the oscillator to input terminal A, and
set it to 2 kHz; adjust for 10 cm ofdeflection. Note
5-8. ADJUST DC BALANCE AND VERTICAL CALI- reading on the vtvm.
BRATION. A small screwdriver is required for this
adjustment. c. Set the oscillator to 200 kHz and output to pre-
vious reading on the vtvm. The deflection should be
a. Check the vertical dc balance as shown in at least 7. 07 cm (3 db down point).
Figure 3-9.
d. Repeat above procedures for channel B.
b. Check the vertical sensitivity calibration as
shownin Figure 3-10. If these controls do not function 5- 11. VERTICAL AMPLIFIER COMMON-SIGNAL
properly, refer to Vertical Amplifier adjustment pro-
cedures, Paragraph 5- 30 , before proceeding further. REJECTION. A Wide Range Oscillator (such as hp
Model 200CD) and an Adjustable Attenuator (such as
5-9. VERTICAL AMPLIFIER SENSITIVITY. A Volt- hp Model 350D) are required for this check.
meter Calibrator (suchas hp Model 738B) is required
for this check. a. Set the Model 122A/AR controls:
a. Set the Model 122A/AR controls: A VERT SENSITIVITY - * .01 VOLTS/CM
A VERT SENSITIVITY VERNIER * * * * CAL
VERT PRESENTATION - * * * * - * * * * *A SWEEP TIME - . 0 .5 MILLISEC/CM
A VERT SENSITIVITY- - DC, .01 VOLTS/CM VERT PRESENTATION. - * * * * * * * A
A VERT SENSITIVITY VERNIER * - * CAL TRIGGERLEVEL. - * - * - * * * AUTO
1 TRIGGER LEVEL 0 - Max ccw, not in AUTO SyNC .................... ~T
b. ConnectaO. 1 volt ac signal from the calibrator b. Connect the oscillator to the channel A input
to input terminal A. The vertical trace should be 10 terminal through the adjustable attenuator terminated
cm *3% (9.7 - 10.3 cm). not, refer to Vertical with 600 ohms.
00081-4 5- 1 |
ACEC
HEWLETT-PACKARD
