User's Manual

Programming Mode
The programming mode allows the user to retrieve or program TX /RX frequencies,
when pin 9 of J1 is set to ground. Programming mode will Inhibit ,
Serial communications can then be made in order to read/program the on- board
EEPROM ( IC5 )which contains radio- specific data.
EEPROM
Relevant channel information, such as Rx/ Tx frequencies, is stored in the EEPROM( IC5)
which is a 93C46. This information may be programmed and erased via the D- type socket.
The EEPROM has 1024 (8x128) capacity and is written serially.
Power supply circuit
The data radio is supplied with a nominal + 13.8V dc power supply input from external
equipment which is filtered using C33. This supply is converted into 8V
voltage levels on the board using the regulator IC2 and associated components .
The +5V VCC is regulated by Zener diode D1 and filtered using C9 and Q9. This +5V
line is fed to the CPU circuit .
4. PERFORMANCE TEST AND ALIGNMENT
The alignment and performance test procedures assume the use of the following equipment.
Discrete test equipment
Volt Meter Spectrum Analyser and notch filter(option)
RF Power Meter. Coupler (20dB isolation)
DC Power Supply, 0-15V 2A min Distortion Meter
Oscilloscope, 20 MHz dual beam
RF Frequency Counter,
100 kHz - 600 MHz
AF Signal Generator 0 – 20 kHz
RF Signal Generator
SINAD Meter
Modulation Meter
Audio Power Meter
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