Escort EGC-3236A - Adjustment Procedures; Required Test Equipment; Adjustments

14
Adjustment Procedures
Caution
The following instructions are for qualied service personnel only. To avoid electrical shock, do not
perform any servicing other than contained in the operation instructions unless you are qualied to do so.
Before calibrating and adjusting, make sure that the instrument has warmed up for at least 2 hours.
Required Test Equipment
The following Table lists the test equipment necessary to perform the adjustments and the maintenance of this instrument. Any equipment
that satises the critical specications given in the table may be substituted for the recommended model.
Instrument Type Required Specications
Oscilloscope 100 MHz bandwidth, dual channel
DVM 4.5 digits, true RMS
Counter 100 MHz, 2 CH, time interval capability
Distortion Analyser 10 Hz – 100 KHz, ± 0.1%
Function Generator 10 MHz frequency
Termination Feed through termination 50 ohm
Cable Assembly BNC-BNC, 50 ohms, RG-58
BNC Adapters BNC to banana, BNC tees
Adjustments
A: Frequency Counter and Oscillator
Adjustments
1. Press EXT-COUNTER switch on front panel. Connect
external source (sine waveform, 10MHz, amplitude of 10
mV rms). Connect a probe to TP600 and to the scope.
Adjust R610 for a square wave display on the scope.
2. Remove the probe from TP600, then adjust C104 for
counter reading to 10.0000~10.0002 MHz.
B: Function adjustment of Triangle
wave
1. Set the controls as follows:
FUNCTION TRIANGLE
AMPLITUDE MAX
DC OFFSET OFF
FREQUENCY 10 KHz
SYMMETRY OFF
SWEEP OFF
2. Adjust R225 for a symmetrical around zero waveform.
3. Press MODE switch to TRIG. Adjust R220 for a zero base
line (0V ±10 mV) on the oscilloscope.
C: Function adjustment of Square wave
1. Set the controls as follows:
FUNCTION SQUARE
AMPLITUDE MAX
DC OFFSET OFF
FREQUENCY 10 KHz
SYMMETRY OFF
2. Adjust R340 for a symmetrical square wave around zero.