GW Instek GFG-8210A - Manual (Page 12)

FUNCTION GENERATOR
USER MANUAL
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(D) Using the Square wave test the characteristics of amplifier circuit.
It can’t actually explain the transient response of amplifier by using
Sine wave for the frequency response curve observation, but using
the high order poly-wave, Square wave, instead to display its
waveform from the oscilloscope can show up many characteristics of
amplifier.
(a) Using the circuit of figure 5, the 50Ω connector trim the
oscillation effect of Square wave.
(b) Use the output of Triangle wave, adjust the amplitude until there
are no clipping happened in the applied frequency.
(c) Select Square wave, adjust frequency, choose to watch the
waveform of middle of amplifier pass band, like 20Hz, 1kHz,
10kHz and etc.
(d) The output waveform of (c), must get something with frequency
Figure 6 shows some possible conditions.
CAUTION: The composed poly-wave frequency of
Square wave is quite large, so it’s not suitable for the
narrow band amplifier testing.
(E) Test of logic circuit
This equipment is suitable for logic circuit testing. Using Square or
Pulse wave can analyze or watch the frequency waveform of a
designed testing circuit. Also the DC Offset effect, drive the plug-in
model board or logic circuit trouble-shooting and etc. Used as
signal tracing and signal replacing operation:
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USER MANUAL
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(a) Connect the lines as Figure 7.
(b) According to the operation guide in this manual, set Square wave
or Pulse wave output.
(c) Use the label TTL, CMOS output terminal testing TTL logic
circuit.
(d) To test CMOS circuit by pulling up the switch of TTL/CMOS,
and adjust CMOS level by rotating the switch to set the proper
level
(e) Use dual-trace scope to show the input-output timing relation
judged by the two waves shown in Figure 4.
(F) Testing of speaking and impedance network
This equipment can be used to test the frequency characteristics of
speaker or any impedance network. It also can get the resonant
frequency of network.
(a) Connect the device under test as in Figure 8, can use oscilloscope
instead of voltmeter.
(b) When use voltmeter, adjust the frequency of instrument record
down voltage relative to frequency.
(c) When testing speaker, if there is a peak volt value, when in low
freq., this must be the resonant freq. of this speaker, see Figure
10. Whether installation may cause any effect to this frequency
or not? The proper design of case-installation will cause two
small ramps on both sides of this sharp ramp.
(d) In testing other impedance network, the resonant may not occur
in low frequency. But in approaching the resonant frequency,
there are still increasing in voltage, then the impedance can be
tested as following: