Tektronix 2246 1Y, Service Manual

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Performance Check Procedure—2246 1Y and 2246 Mod A Service
o. Set:
CH 3 (CH 2 off)
0.1 V
Fully CW
g. Set X I 0 MAG On (for 2 ns/div sweep speed).
h. CHECK—that the leading edges of the two
waveforms have less than 0.2 horizontal division
separation at the center graticule line, excluding
trace width.
Vertical MODE
CH 3 and CH 4
VOLTS/DIV
CH 3 POSITION
p. CHECK—that the bottom of the waveform is
above the center graticule line.
q. Set CH 3 POSITION fully CCW.
r. CHECK—that the top of the waveform is below
the center graticule line.
s. Set:
14. CH 1 to CH 4 Signal Delay Match
a. Set Vertical MODE to CH 1 and CH 4 (CH 2 off).
b. Move the CH 2 signal to the CH 4 input
connector.
c. Superimpose the CH 4 waveform on the CH 1
waveform.
CH 3 POSITION 12 o ’ clock
Vertical MODE CH 4 (CH 3 off)
t. Repeat the procedure for CH 4.
d. CHECK—that the leading edges of the two
waveforms have less than 0.4 horizontal division
separation at the center graticule line, excluding
trace width.
u. Set CH 4 POSITION to 12 o ’ clock.
v. Disconnect the test setup from the 2246 1Y or
2246 Mod A.
15. CH 3 to CH 4 Signal Delay Match
a. Set:
13. CH 1 to CH 2 Signal Delay Match
a. Set:
Vertical MODE
CH 1 and CH 2
Input COUPLING
CH 1 and CH 2
VOLTS/DIV
SEC/DIV
Trigger SOURCE
CH 1 and CH 2
(CH 4 off)
DC
0.1 V
20 ns
CH 3
Vertical MODE CH 3 and CH 4
(CH 1 off)
Trigger SOURCE CH 2
b. Move the CH 3 trigger signal to the CH 2 input
and the CH 1 signal to the CH 3 input.
c. Superimpose CH 3 and CH 4 waveforms at the
center graticule line, using the HORIZONTAL
POSITION control, if necessary.
d. CHECK—that the leading edges of the two
waveforms have less than 0.2 horizontal division
separation at the center graticule line.
b. Superimpose the CH 1 and CH 2 traces at the
100% graticule marking.
e. Disconnect the test setup.
c. Connect calibration generator (PG 506) FAST
RISE, rising-edge signal to the CH 1 and CH 2
inputs via a 50 f l precision BNC coaxial cable, a
50 XT BNC termination, and a BNC dual-input
coupler.
d. Connect calibration generator TRIG OUT signal to
the CH 3 input via a 50 XI BNC coaxial cable and
a 50 XT BNC termination.
e. Set the calibration generator to FAST RISE and
adjust PULSE AMPLITUDE for five divisions of
signal amplitude at 1 MHz.
16. CH 1 and CH 2 Vertical Bandwidth
a. Set:
X I 0 MAG
Vertical MODE
SEC/DIV
CH 1 VOLTS/DIV
CH 1 and CH 2 Input
COUPLING
Trigger SOURCE
Horizontal POSITION
Off
CH 1 (CH 3 and
CH 4 off)
0.1 ms
5 mV
DC
VERT
12 o ’clock
f. Position the rising edges of the superimposed
waveforms horizontally to the center vertical
graticule line.
b. Connect leveled sine-wave generator (SG 503)
output to the CH 1 input via a 50 XT precision
BNC coaxial cable and a 50 XT BNC termination.
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