Sangean U-3, Service Manual

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ALIGNMENT INSTRUCTIONS
1. ALIGNMENT FOR AM
a. Required Instruments:
AM IF Sweep Generator with scope
b. Alignment Procedure
Mode Adjustment Procedure
(1) Press the power button to turn on the radio.
(2) Connect the input terminal of AM IF sweep generator in series with a resistor of 1.2K
Ω
to the C28 positive and TP14.
(3) Connect the RF output terminal of AM IF sweep generator to another test point TP3.
(4) Connect a 100
μ
F electrolytic capacitor to test point TP14 and theC28 positive .
(5) Adjust T3 to have a max. output with a marker frequency of 450 kHz on the sweep
AM T3
scope.
c. Instrument Connection
T3
C28+ TP14
100uF
IN
TP1
RF
TP3
TP14
OUT
450KHz Marker
1.2K Ω 2.2K Ω
AM IF Sweep Generator
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