Horizontal; A And B Sweep Length; Horizontal Position Range; Var Sec/Div Range - Tektronix 2246 1Y Service Manual

Performance Check Procedure—2246 1Y and 2246 Mod A Service
Equipment Required (See Table 4-1)
Tim e-m ark generator
50 Q BNC termination

1. A and B Sweep Length

a. Set:
READOUT (Intensity)
A INTEN
Vertical MODE
CH 1 and CH 2
Input COUPLING
CH 1 VOLTS/DIV
Horizontal MODE
A SEC/DIV
Horizontal POSITION
A/B SELECT
Trigger MODE
Trigger SOURCE
Trigger CPLG
Trigger SLOPE
Trigger HOLDOFF
Trigger LEVEL
Measurements
FOCUS
b. Connect tim e-m ark generator (TG 501) to the
CH 1 input via a 5 0 -0 BNC coaxial cable and a
5 0 -0 BNC termination.
c. Set generator for 2 ms time marks.
d. CHECK—sweep length of the A trace is greater
than 10 divisions.
4-18

HORIZONTAL

e. Set:
Horizontal MODE
B SEC/DIV
A/B SELECT
Trigger MODE
|< - o r
For a viewable
readout
For a viewable
B INTEN
trace
CH 1 (CH 2 off)
f. CHECK—the Delay Time readout is 70.000 ms,
DC
and the B Sweep length is greater than 10
0.5 V divisions.
A
2 ms

2. Horizontal POSITION Range

12 o ' clock
a. Set:
A Trigger
AUTO LEVEL
Horizontal MODE
VERT
Horizontal POSITION
AC
_ r (positive)
b. CHECK—that the start of trace positions past the
Min center vertical graticule line.
12 o ' clock
c. Set Horizontal POSITION fully CCW.
All off (press
CLEAR
d. CHECK—that the 11th time marker is positioned
DISPLAY three
to the left of the center vertical graticule line.
times)
For best

3. VAR SEC/DIV Range

defined display
a. Set:
SEC/DIV
SEC/DIV VAR
Horizontal POSITION
b. Set time mark generator for 5 ms time marks.
c. CHECK—the tim e-m ark spacing is equal to or
less than two divisions.
d. Set SEC/DIV VAR fully CW (calibrated detent).
50 £1 BNC coaxial cable
DELAY Control
B
1 ms
B Trigger
RUNS AFTER
CCW to the
lowest DELAY
readout value
For a visible
display
A
Fully CW
1 ms
Fully CCW
12 o 'clock