Tektronix 323, Инструкция по эксплуатации

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Performance Check— Type 323
through the GR to BNC adapter, 42-inch 50-ohm BNC cable,
10X BNC attenuator and the 50-ohm BNC termination.
c. Set the constant-amplitude generator for a four-divi­
sion display, centered about the center horizontal line, at
its reference frequency (50 kilohertz).
d. Without changing the output amplitude, increase the
output frequency of the generator until the display is re­
duced to 2.8 divisions (—3dB point).
e. CHECK— Output frequency of generator must be four
megahertz or higher.
18. Check X 10 V ertical G ain U pper B an d w id th
Lim it
REQUIREMENT— Not more than —3 dB at 2.75 megahertz.
a. Pull the X 1 0 VERT GAIN switch out.
b. Set the constant-amplitude generator for a four-divi­
sion display, centered about the center horizontal line, at
its reference frequency (50 kilohertz).
c. Without changing the output amplitude, increase the
output frequency of the generator until the display is re­
duced to 2.8 divisions (—3 dB point).
d. CHECK-—Output frequency of generator must be 2.75
megahertz or higher.
e. Disconnect all test equipment.
19. Check A C -C oupled Low er V ertical
B a n d w id th Limit
REQUIREMENT— Not more than —3 dB at two hertz.
a. Connect the low-frequency constant-amplitude gener­
ator to the VERT INPUT connector through the 42-inch 50-
ohm BNC cable and the 50-ohm BNC termination.
b. Change the following control settings.-
INPUT AC
X 10 VERT GAIN Pushed in
TIME/DIV .5 s
c. Set the low-frequency generator for a four-division
display, centered about the center horizontal line, at a refer­
ence frequency of one kilohertz.
d. Without changing the output amplitude, reduce the
output frequency of the generator to two hertz.
e. CHECK— CRT display 2.8 divisions, or greater, in
amplitude (not more than —3 dB).
f. Disconnect all test equipment.
a. Change the following control settings:
VOLTS/DIV .5
INPUT DC
TIME/DIV 1 ms
b. Connect the time-mark generator to the VERT INPUT
connector through a 42-inch 50-ohm BNC cable and a 50-
ohm BNC termination.
c. Set the time-mark generator for five-millisecond mark­
ers.
d. Position the middle marker (three markers on total mag­
nified sweep) to the center vertical line (see Fig. 5-4A).
e. Pull the X 10 HORIZ MAG switch out. Be careful not
to change the knob position as the X 1 0 HORIZ MAG
switch is pulled out.
f. CHECK— Middle marker should be within one divi­
sion of the center vertical line (see Fig. 5-4B).
(A )
(B)
Fig. 5 -4 . Typical CRT d isp la y showing correct m a g n ifie r re gistratio n;
IA ) X 1 0 HORIZ M A G switch pushed in f (B) X l O HORIZ M A G
switch pu lle d out.
20. Check M a g n ifie r R egistration
REQUIREMENT— Less than one-division shift of marker at
center vertical line when switching X 1 0 HORIZ MAG on
(pulled out).
21. Check N o rm a l Sweep Tim ing Accuracy
REQUIREMENT —5 ns to .2s/DIV, within 3% over middle
eight divisions of the display; .5 s and 1 s/DIV, within 4%
over middle eight divisions of display.
5-6