Tektronix 3B5, Инструкция по эксплуатации

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Performance Check —Type 3B5
c. Set the constant-amplitude generator for a 0.5-division
CRT display (0.5 volt peak to peak) at 50 kilohertz.
d. CHECK— Stable CRT display can be obtained with
the LEVEL control for both + and — slope triggering.
e. Set the constant-amplitude generator for a 0.5 division
display at 20 megahertz (this check can be made only with
an amplifier unit which has a bandpass of at least 15 MHz).
f. Set the MANUAL TIME/DIV switch to .1 /zs.
g. CHECK —Stable CRT display can be obtained with the
LEVEL control for both + and — slope triggering.
h. Set the Trigger Function switch to INT-AUTO.
i. CHECK—Stable CRT display can be obtained with the
LEVEL control for both + and — slope triggering. The
Auto Trigger light must be on.
j. Set the Trigger Function switch to EXT-AC.
k. Set the constant-amplitude generator for a one-division
CRT display (one volt peak to peak) at 50 kilohertz.
l. Set the MANUAL TIME/DIV switch to 20 /is.
m. CHECK— Stable CRT display can be obtained with the
LEVEL control for both + and — slope triggering.
n. Set the Trigger Function switch to EXT-DC.
o. CHECK— Stable CRT display can be obtained with the
LEVEL control for both + and — slope triggering.
p. Without changing the output amplitude, set the con ­
stant-amplitude generator to 20 megahertz.
q. Set the MANUAL TIME/DIV switch to .1 /is.
r. CHECK — Stable CRT display can be obtained with the
LEVEL control for both + and — slope triggering.
s. Set the Trigger Function switch to EXT-AC.
t. CHECK — Stable CRT display can be obtained with the
LEVEL control for both -|- and — slope triggering.
u. Disconnect all test equipment.
Fig. 5-2. Typical CRT display showing correct basic timing.
e. CHECK —CRT display for one marker each division
between the first and ninth vertical graticule lines (see Fig.
5-2).
NOTE
Unless otherwise noted, use the middle eight hori ­
zontal divisions when checking timing (see Fig.
2-4, Operating Instructions section).
f. ADJUST — CAL adjustment, R515 (on front-panel), for
one marker each division. (This adjustment should be
checked and readjusted as necessary when the Type 3B5 is
inserted into a plug-in compartment other than the one in
which it was calibrated.)
7. Check Basic Timing
REQUIREMENT—Correct timing at 1 ms/DIV.
a. Change the following control settings:
MANUAL TIME/DIV 1 ms
Trigger Function INT-AUTO
LEVEL Midrange
SLOPE +
Volts/Division 0.5 Volt
(amplifier unit)
b. Connect the time-mark generator to the amplifier unit
input connector through the 50-ohm BNC cable and a 50-
ohm BNC termination.
c. Set the time-mark generator for one millisecond
markers.
d. Position the second marker to the first graticule line
with the POSITION control.
8. Check Variable Control Range
REQUIREMENT — At least 2.5:1.
a. Set the time-mark generator for 1 0-millisecond markers.
b. Position the markers to the far left and right vertical
graticule lines with the POSITION control.
c. Turn the VARIABLE control fully counterclockwise.
d. CHECK— CRT display for four-division maximum spac­
ing between markers (2.5:1 range, see Fig. 5-3). UNCAL
readout must come on and s/DIV readout must be off when
VARIABLE control is out of the CAL position.
e. Return the VARIABLE control to the CAL position.
9. Check Sweep Length
REQUIREMENT — Normal sweep, 10.3 to 11.3 divisions;
magnified sweep, 12 to 15 divisions.
5-4