Kenwood CO-1506, Инструкция по эксплуатации

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APPLICATIONS
Fig. 6. Representative Lissajous" patterns
MEASURING AUDIO AMPLIFIER F R E Q U E N C Y
RESPONSE
Supply a sine wave to the A U X terminal of the audio
amplifier from a signal generator and connect the speaker
output terminals of the amplifier to V . I N P U T (1) and
G N D ( 2 ) . T h e audio amplifier may have a typical fre-
quency response as shown in Fig. 8. T h i s response,
however, will vary as shown in Fig. 9 by using the tone
control or loudness control.
T h e amplifier frequency response should be measured by
reading the amplitude displayed on C R T for each of
different frequencies while maintaining the signal generator
at a constant output level.
C A U T I O N :
When H. I N P U T (8) is used, the frequency response of the
horizontal amplifier varies according to the position of the
V A R / H . G A I N (10) knob (approximately 2 5 k H z at the
center position).
It is advisable to set V A R / H . G A I N (10) to the position of
a highest possible again.
If the input signal is large, the measurement should be
performed with an attenuator inserted between the G N D
(7) and H. I N P U T (8) as shown in Fig. 7. In this case,
V A R / H . G A I N (10) should also be set to the position of a
highest possible gain.
A T T E N U A T I O N 1/100
Fig. 8 An example of frequency response
Fig. 7 Connection of attenuator
Fig. 9 Frequency response affected by the tone
and loudness controls
8
180° 135° 90° 45° 0°
( 2 2 5 ° ) ( 2 7 0 ° ) (315° ) ( 3 6 0 ° )
A T T E N U A T I O N 1/10