Kenwood CO-1506, Инструкция по эксплуатации

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SQUARE WAVE SIGNALS AND F R E Q U E N C Y
R E S P O N S E
Use of a square wave in place of the sine wave will provide
an approximate frequency response of the amplifier by
checking the output waveform of the square wave.
The above same connections also apply to the response
check of T V receivers for either the video I F or audio I F
response. Use point B for measurements of F M receiver I F
transformers and tracking, and use point A for detector
adjustment.
ALIGNING THE IF RESPONSE OF FM OR TV
SETS
T o check the overall response of the intermediate fre-
quency transformers of an F M receiver, the S W E E P
R A N G E (6) should be set to E X T position. Then connect
the output leads of a sweep generator to the mixer and
chassis of the receiver and the sweeep output to the H.
I N P U T of the oscilloscope. A l s o , connect the oscilloscope
to the test point or output terminal of the limiter of the
F M receiver. T h i s connection may be made by using a
shielded cable with about 1 0 0 k n resistor provided at the
point of connection to the receiver. T h e oscilloscope
should be set to the maximum sensitivity while the sweep
generator output level should be set as low as possible. T h e
cable from the sweep generator and other leads from
CO-1506 must be adequately away from the body of the
receiver or must not cross each other to avoid interaction.
T V receiver
Sweep generator
1 0 . 7 M H z
7 6 - 9 0 M H z
Sweep
generator
Ratio detector
output
4 . 5 M H z
9
Sweepin
g
outpu
t
To the E X T S Y N C / H . I N P U T terminal of CO-1506
Fig. 10 Viewing the SF frequency responses
T o CO-1506
To CO-1506
_Detector
joutputl
FM receiver
Frequency response of amplifier
Square wave output
lOOHz
I K H z
Gain reduced at high-frequency
Gain rises at high-frequency
Gain reduced at low-frequency
Gain rises at low-frequency
With loudness control set ON.
Gain having waving characteristic curve
2
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