Alignment Procedure; Base Unit - Toshiba FT-7800A Service Manual

Base Unit

Transmitter Section
Connections
Power
Meter
Frequency
Counter
Deviation
Meter
Preset
a) Connect the AC adapter to the base unit while pressing the "PAGE" key, and keep pressing it continuously for
approximate 2 seconds.
b) Release the "PAGE" key when entering TEST mode 1 with IN USE LED lighting.

Alignment Procedure

Step Adjustment
RT3
1
(TX Power)
CT1
2
(TX Frequency)
RT4
3
(TX Modulation)
Alignment Point Location on Base Main PCB and Base RF PCB
ALIGNMENT PROCEDURE
RF
Test Point
DC IN
9V Jack
RF
Test Point
Connect the Power Meter to the RF test point on the Base MAIN PCB. Adjust
RT3 for a −6.0 dBm reading on the Power Meter.
Connect the Frequency Counter to the RF test point on the Base MAIN PCB.
Adjust CT1 to make sure that the frequency is 925.908974 MHz.
Press the "PAGE" key to enter the TEST Mode 2. Connect the AF Generator to
the TEL Line Jack on the Base Main PCB. Make sure that the output is 1 kHz
77.5 mV from the AF Generator.
Connect the Deviation Meter to the RF test point on the Base MAIN PCB.
Adjust RT4 to indicate ±20 kHz Dev.
CT1
RT4
BASE Unit
J2 J1
TEL Line 1kHz 77.5mV
Jack
Remarks
RF PCB
RT3
— 3 —
AF GEN.
AC
AC 120V
Adapter
60Hz
J1
TEL LINE Jack
J2
DC IN 9V Jack
RF
TEST POINT