TB 9-6625-2164-24
IDENTIFICATION AND DESCRIPTION
1. Test Instrument Identification.
This bulletin provides instructions for the
calibration of Digitizer, Tektronix, Type 7D20. The manufacturer's manual was used as the
prime data source in compiling these instructions. The equipment being calibrated will be
referred to as the TI (test instrument) throughout this bulletin.
a. Model Variations. None.
b. Time and Technique. The time required for this calibration is approximately 5
hours, using the dc and low frequency technique.
2. Forms, Records, and Reports
a. Forms, records, and reports required for calibration personnel at all levels are
prescribed by TB 750-25.
b. Adjustments to be reported are designated (R) at the end of the sentence in which
they appear. When adjustments are in tables, the (R) follows the designated adjustment.
Report only those adjustments made and designated with (R).
3. Calibration Description. TI parameters and performance specifications which
pertain to this calibration are listed in table 1.
Table 1. Calibration Description
Test instrument
Performance specifications
parameters
Vertical gain
Range: 5 mV/division to 5 V/division in 1, 2, 5 sequence
Accuracy: Within 2% with AQR GAIN adjusted at 10 mV/division
Vertical linearity
0.12 division or less expansion or compression of a center screen 2 division signal
parameters positioned anywhere within the 4 division graticule area
Dc to 70 MHz
Trigger sensitivity:
Triggering frequency range
Maximum vertical signal required
Internal
External
Ext +1 0
Ac coupled
30 Hz to 30 MHz
0.4 division
60
mV
0.6 V
30 to 70 MHz
1.0 division
150
mV
1.5 V
Ac LF REJ
50 kHz to 30 MHz
0.4 division
60 mV
0.6 V
30 to 70 MHz
1.0 division
150 mV
1.5 V
Ac HF REJ
30 Hz to 30 kHz
0.4 division
60 mV
0.6 V
Dc HF REJ
Dc to 30 kHz
0.4 division
60
mV
0.6 V
Dc
Dc to 30 MHz
0.4 division
60
mV
0.6 V
30 to 70 MHz
1.0 division
150
mV
1.5 V
Max signal
---
+6 division
+1.0 V
+10 V
P-P
30 to 200 Hz
2.0 division
300
mV
3.0 V
200 Hz to 30 MHz
0.6 division
90
mV
0.9 V
30 to 70 MHz
1.2 division
200
mV
2.0 V
Range: 1 s to 5 s/division
1
Stored timing
Cursor No. 1
Accuracy: 0.1% of reading +0, -1 sample interval 300 ps
Resolution Vertical
Accuracy: Nominally 0.04 division
1Not
verified at 5 s.
