Tektronix 570, Manual

Page: 46 / 134

test
point
Fig.
5-3. High
Voltage test
points.
+ DC connector on the test panel and ground.
Set the +
DC
Control and the RANGE DC VOLTS
Control as called out in the table below.
Using the + DC VARIABLE Contro I, set the
voltage of the + DC connector on the test panel
to the value called out in the table. The
voltage is set to the proper value by using the
accurate voltmeter connected to the + DC
connector on the test panel. After the voltage
is set then the reading of the meter mounted
on the Type 570 is compared to that of the
accurate voltmeter.
The meter mounted on
the Type 570 should not be off the proper
r eading by more than 2% in any of its ranges.
METER ACCURACY CHECK
V oltage at + DC Control RANGE DC
+ DC Connector
VOL TS Control
(test panel)
300v
300 700
300v
300 350
200v
200 350
100v
100
350
100v 100
140
70v 100
140
70v
100
70
35
50
70
35
50
35
1 4
20
35
1 4 20
1 4
7 20
1 4
7
20
7
NOTE
If the + DC VARIABLE will not
reduce the output
of the
+
DC
connector to 7 volts then change
V540B.
By changing this tube it
is usually possible to obtain a 7
volt output or less.
4.
-
D C Control Check
Connect the accurate voltmeter between
ground and the -DC connector on the test
panel.
Turn the -DC Control clockwise and
m ake sure that the voltage output of the -DC
connector goes from 0 to -100 volts.
5.
Grid A, Grid B and
-
1 50 27
k Connector
check
Connect the voltmeter between the GRID A
connector and ground, the voltmeter should
read approximately - 10 8 volts. Now move the
TEST POS ITION switch to GRID B . The volt­
meter should still read - 1 0 8 volts.
Remove the voltmeter lead from the GRID A
connector and connect it to the GRID B connect ­
o r on the test panel. Move the TEST POSITION
switch to the OFF position , the voltmeter will
now read approximately - 1 08 volts.
Now
move the TEST POSITION switch to GRID A
pOS ition , the voltmeter will once again show
the approximate - 10 8 volt reading.
After checking the GRID A and GRID B
connectors on the test panel, move the volt­
meter lead from the GRID B connector and
connect it to the - 1 50 27k connector on the
test panel. The voltmeter should read - 1 50
volts from this connector.
6. CRT A l i g n m e n t
S e t the INTENSITY Control to a usable
level. Adjust the FOCUS and ASTIGMATISM
Controls for a focused spot. Now switch the
VOL TS/DIV Control to 1 0 . This will result in
a horizontal line across the face of the crt.
With the V E RTICAL POSITIONING Control
position the line under one of the horizonta
i
graticule lines.
Crt adjustment
SN 1 0 1 - 5 1 99
If the trace and graticule line do not coin­
cide over the length of the graticule , loosen
5 - 4 C alibration Procedure - Type 570