Alinco DX-SR9 E, Service Manual

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The IC102, resetting IC for resetting the CPU, turns on and off at 4.5V. When
OFF (0V) the CPU resets. Then the IC1004’s reset signal goes Low and the
CPU stops. The IC116 is the power supply for the CPU, which is made
separate in order for the voltage to sustain 5V until the data is written to the
EEPROM and resetting signal is input.
A regulated power supply of 8V is made of the IC115. The voltage of 8V is
supplied to D3, D4, D5 and D6. The CPU’s EN output is a pulse, which current
value from D3 to D6 is set. When the illumination is at the highest intensity, the
EN output is constant at 5V.
The CPU turns ON the LCD via segment and common terminals with 1/4 the
duty and 1/3 the bias, at the frame frequency of 125Hz.
The CPU (IC101) is equipped with an internal tone encoder. The tone signal
(67.0 to 250.3Hz) is output from pin 45 of CPU. The output of the CPU leading
to the mic amp LPF having mixed with audio signal. The tone is output only
when in FM mode.
The CPU (IC101) is activated by input to pin No.68 for dots, and pin No.69 for
dash. When ElecKey is ON, the electronic keyer in ON, and when Eleckey is
OFF the keying is of semi-automatic (the “bug key”) operation.
The pin 58 of CPU is clone data transmission, and the pin 57 of CPU is
receiving data. Each data is of one line, and input/output is done thru JK2 on
the front unit.
The X1 is a ceramic resonator of 8MHz carefully chosen on its harmonics not
interfering on amateur bands. For the front panel switches, the Y0, Y1, Y2 and
Y3 with regard to the DB0~DB5 are monitored to determine which key is
pressed. On the terminals of RIT and IF-Shift pots, 5V is applied and the
voltage at the input of A/D determines the positions of these pots. The Q1 is for
transmit detection whose output from the main unit and illuminating the Tx
LED. For this reason it cannot be directly input to the CPU therefore the change
is only either on or off. The Q2 is the squelch output from the main unit which
illuminates the Rx LED.
8. Power Supply and Resetting
9. Dimmer
10. LCD
11. Tone
12. Electronic Keye
13. Cloning
14. Miscellaneous
In SDR receiving, 26th pin(SDR) of CPU (IC101) becomes H. Through the
analog switch IC1014 , the received signal of 455KHz, which is amplified by
Q110 then amplified again by Q1002.
On the other hand, BFO (1.82MHz) signal generated by IC604 is divided into
1/4 and in-phase and quadrature signals of 455KHz. This standard signal and
receiving signal amplified by Q1002 are mixed at IC1003 and output as I/Q
signal to JK1003.
In SDR transmitting, the 27th pin(SDT) of the CPU (IC101) becomes H. The I/Q
mixture signal with ±12KH
ｚ
carrier frequencies input through the center
terminal of JK1004 goes through IC1017 internal amp circuit and IC1004 buffer
amp. This signal is mixed with a signal of 467KHz came from BFO in a mixer
circuit of Q1016, then finally output as IF signal of 455KHz.
Such 455KHz signal will be output through the same circuit and transmitted
through the 455KHz IF filter of each modes. In SDR operation, when the mode
is changed, the CPU generates appropriate mode signal accordingly.
After amplification in IC123 operational amplifier, the signal from the
microphone is rectified to a DC voltage at D1007, D191.
The rectified voltage that is applied to the CPU 81 pin analog input, transmits
with microphone sensitivity determined by the voltage value.
The data signal input through the center terminal of JK1004 is amplified by
IC1018 then goes through the IC1007 and IC119 microphone amp, passes the
same modulation line as a voice signal and transmitted as a PSK signal.
To transmit, the data signal is rectified by D1002 and D1004, then the rectified
signal toggles Q1011 and inputs L to the 77th pin of the CPU
15. SDR Mode
16. VOX Circuit
17. DATA VOX circuit