Sangean DPR-25+, Service Manual

Page: 10 / 46

4. ALIGNMENT FOR AM/LW SENSITIVITY
a. Required Instruments
AM Signal Generator
SSVM
b. Alignment Procedure
Mode Adjustment Procedure
(1) Turn on the radio.
(2) Connect a SSVM to the speaker TP7 and TP8 terminals.
(3) Connect an AM signal generator together with standard loop dummy antenna and
feed 30% modulated signal to the AM ferrite bar antenna L12.
(4) Tune the generator frequency to 1404 kHz.
(5) Tune the AM frequency to 1404 kHz and adjust TC3 to have a max reading on
SSVM.
(6) Return the generator frequency to 603 kHz.
(7) Tune the AM frequency to 603 kHz and adjust L12 to have a max reading on
SSVM.
AM
TC3
L12
(8) Repeat (4) to (7) as necessary to minimize tracking error.
c. Instrument Connection
L12
TC3
60 cm
The radio is located
perpendicularly to
the Loop Antenna
Loop Antenna
AM Signal Generator
TP8
TP7
DVM
10