Tektronix FG501, Инструкция по эксплуатации

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Adjustment—FG 501
Initial Control Settings
Set the following controls during warm-up time:
FG 501
5. Adjust Square-Wave High-frequency
Compensation and Check Risetime
Control Setting Changes:
FUNCTION
AMPL 1
OFFSET 2
PHASE
FREQ
VERNIER
MULTIPLIER
FREQUENCY Hz
Triangle
Fully cw
In (off)
Off (pushed
in, set to 0°)
Calibrated (fully cw)
10“
1
FUNCTION
Time/div
Volts/div
Input Coupling
FG 501
Square wave
Oscilloscope
2 μ s (Mag off)
2 V
D C
DM 501
Range/Function switch 20 DC Volts
PROCEDURE
(SN B020000 and up)
1. Reference Current Adjustment (+13.8 V de)
a. Connect the digital voltmeter Lo input lead to
ground (at negative end of C400). Connect the Hi input
meter lead to TP1 on the FG 501 (see Fig. 3-1).
b. ADJUST —R400 (Reference Current) for a meter
reading of +13.8 V d c.
2. +20 Volt Supply Adjustment
a. Move the digital voltmeter Hi input lead to TP3 on
the FG 501.
b. ADJUST —R415 (+20 Volts) for a meter reading of
+20.0 V de.
3. +17 Volt Supply Check
a. Move the digital voltmeter Hi input lead to TP8 on
the FG 501.
b. CHECK—for a meter reading of+17 V dc, ±200 mV
(+16.80 V to +17.20 V).
4. —17
Volt Supply Check
a. Move the digital voltmeter Hi input lead to TP9 on
the FG 501.
b. CHECK—for a meter reading of—17 V dc, ±200 mV
(-17.20 to -16.80 V).
c. Disconnect the digital voltmeter leads from the
FG 501.
'Below SN B130000 AMPL control is labeled OUTPUT.
Tor SN below B1 30000 set OFFSET to zero.
a. Connect the FG 501 OUTPUT connector through a
50 QQ coaxial cable to a 500 termination at the os­
cilloscope vertical input connector. Check that the display
amplitude is at least 10 V peak-to-peak (SN B130000-up);
7.5
V peak-to-peak for SN below B130000.
b. Set the oscilloscope variable volts/div, triggering,
intensity, focus, and position controls for a visible,
triggered, vertically-centered five-division display.
c. ADJUST — C281 (square-wave high-frequency
compensation) for a square front corner and flat top with
minimum aberrations on the positive-going portion of the
square-wave display (this adjustment will affect square­
wave risetime).
d. Set the oscilloscope time base to 20 ns (Mag on).
Set intensity, triggering, and position controls as
necessary to observe the positive-going square-wave
leading edge over approximately five horizontal graticule
divisions.
e. Measure the risetime of the leading edge (refer to
the oscilloscope instruction manual for risetime measure­
ment techniques). Adjust the position controls as re­
quired. At a sweep speed of 20 ns/div, the risetime reading
should be no more than five horizontal divisions between
the 10% and 90% risetime points (100 ns or less).
f. If necessary, repeat parts c through e for a com­
promise between best leading edge and flat top
(aberrations not to exceed 5%) with a risetime of no more
than 100 ns.
6. Dial Calibration
Control Settings:
FG 501
FUNCTION Triangle
Oscilloscope
Time base 10μs
Triggering For triggered display
3-4
REV A, MAR 1979