Kenwood TH-77A Service Manual page 50

TH-77A/E
50
ADJUSTMENT
Required test equipment
1. Stabilized Power Supply
1) The supply voltage can be changed between 5V
and 18V, and the current is 3A or more.
2) The standard voltage is 13.8V.
. DC Ammeter
1) Class 1 ammeter (17 ranges and other features).
2) The full scale can be set to either 300mA or 3A.
3) A cable of less internal loss must be used.
3. Frequency Counter (f. counter)
1) Frequencies of up to 1GHz or so can be measured.
2) The sensitivity can be changed to 250MHz or
below, and measurements are highly stable and
accurate (0.2ppm or so).
. Power Meter
1) Measurable frequency : Up to 5S00MHz.
2) Impedance : 50Q, unbalanced.
3) Measuring range : Full scale of 1OW or so.
4) A standard cable (5D2W 1m) must be used.
. RF VTVM (RF V.M)
1) Measurable frequency : Up to S00MHz or so.
. Linear Detector
1) Measurable frequency : Up to S00MHz.
2) Characteristics are flat, and CN is 60dB or more.
. Digital Voltmeter
1) Voltage range : FS = 18V or so.
2) Input resistance : 1MQ or more.
8. Oscilloscope
1) Measuring range : DC to 30MHz.
2) Provides highly accurate measurements for 5 to
25MHz. ,
9. AF Voltmeter (AF V.M)
1) Measurable frequency : 50Hz to 1MHz.
2) Maximum sensitivity : 1mMV or more.
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Measuring Jigs
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TX-RX UNIT
TX-RX UNIT (RFU)
10. Spectrum Analyzer
1) Measuring range : DC to 1GHz or more.
11. Standard Signal Generator (SSG)
1) Maximum frequency : S00MHz or more.
2) Output : -20dB/0.1pV to 120dB/1V.
3) Output impedance : 50Q
12. Tracking Generator
1) Center frequency : 50kHz to 200MHz.
2) Frequency deviation : +35MHz.
3) Output voltage : 100mV or more.
13. Dummy Load
1) 8Q, 3W or more.
Preparation
e Setthe unitinthe receiving mode and set the controls
as follows, unless otherwise specified.
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e Use a non-conductive rod such as a Bakelite rod for
adjustment (especially of trimmers and coils).
e To protect the SSG, do not send out signals while
adjusting the receiving unit.
e The indicted SSG output levels are for maximum
output.
CONTROL UNIT
%* Connector cable
% Connector cable Parts No. E37-0054-05