Ch 1 To Ch 2 Signal Delay Match; Ch 1 To Ch 4 Signal Delay Match; Ch 3 To Ch 4 Signal Delay Match; Ch 1 And Ch 2 Vertical Bandwidth - Tektronix 2246 1Y Service Manual

Performance Check Procedure—2246 1Y and 2246 Mod A Service
o. Set:
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:
CH 3 POSITION
Vertical MODE
t. Repeat the procedure for CH 4.
u. Set CH 4 POSITION to 12 o ' clock.
v. Disconnect the test setup from the 2246 1Y or
2246 Mod A.

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
b. Superimpose the CH 1 and CH 2 traces at the
100% graticule marking.
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 X T 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 X T BNC termination.
e. Set the calibration generator to FAST RISE and
adjust PULSE AMPLITUDE for five divisions of
signal amplitude at 1 MHz.
f. Position the rising edges of the superimposed
waveforms horizontally to the center vertical
graticule line.
4-10
g. Set X I 0 MAG On (for 2 ns/div sweep speed).
CH 3 (CH 2 off) h. CHECK—that the leading edges of the two
waveforms have less than 0.2 horizontal division
separation at the center graticule line, excluding
0.1 V
trace width.
Fully CW

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.
12 o ' clock
d. CHECK—that the leading edges of the two
CH 4 (CH 3 off) waveforms have less than 0.4 horizontal division
separation at the center graticule line, excluding
trace width.

15. CH 3 to CH 4 Signal Delay Match

a. Set:
Vertical MODE
Trigger SOURCE
b. Move the CH 3 trigger signal to the CH 2 input
and the CH 1 signal to the CH 3 input.
CH 1 and CH 2
(CH 4 off)
c. Superimpose CH 3 and CH 4 waveforms at the
center graticule line, using the HORIZONTAL
DC
POSITION control, if necessary.
0.1 V
d. CHECK—that the leading edges of the two
20 ns
waveforms have less than 0.2 horizontal division
CH 3
separation at the center graticule line.
e. Disconnect the test setup.

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
b. Connect leveled sine-wave generator (SG 503)
output to the CH 1 input via a 50 X T precision
BNC coaxial cable and a 50 X T BNC termination.
CH 3 and CH 4
(CH 1 off)
CH 2
Off
CH 1 (CH 3 and
CH 4 off)
0.1 ms
5 mV
DC
VERT
12 o 'clock