Python implementation of CAT system for Yaesu FT-897ND.
According to Yaesu FT-897D's manual, the CAT System allows the transceiver to be controlled by a personal computer. The purpose of this project is to learn this system for later implementing it using an AVR microcontroller.
The program is written in Python and uses serial library to connect to the transceiver. It runs as console application in text mode.
- This program is provided as is and I'm not responsible for any damage it may cause.
- Before using this program make sure you completely understand what you are doing.
- Before sending any commands to your transceiver make a backup copy of factory calibration settings in service menu. There are sources which state that some commands may completely erase it. This may result in need to send the transceiver to Yaesu for realignment.
Yaesu FT-897D's is connected to PC through a COM port. I used one of many USB to COM boards available on eBay and AliExpress for a couple of dollars. The port is connected to TXD and RXD pins of the ACC connector located on the rear panel of the transceiver. Refer to Yaesu FT-817ND's Operation Manual for more details.
Programming cable can also be used and will work fine with this program.
The program is implemented as FT897 class with following methods:
__init__(self, serial_port, serial_speed, serial_stopbits): constructor which starts serial connection and resets transceiver state variables self._frequency, self._mode, self._squelch, self._s_meter, self._ctcss_dcs, self._discriminator, self._t_mod_t_power, self._t_alc, self._t_vswr and self._t_mod.
read_frequency(self): reads frequency and mode data and stores it in self._freq and self._mode variables.
read_rx_status(self): reads receiver status (S-level, squelch state, CTCSS/DCS code match and discriminator centering) and stores S-level in self._s_meter, squelch state in self._squelch, ctcss/dcs state in self._ctcss_dcs and discriminator status in self._discriminator variables.
get_s_meter_string(self, s_meter): generates S-meter string for second line of output.
get_rx_state_string(self): generates some lines of text which include frequency, modulation, squelch level, ctcss/dcs status, discriminator status when modulation is FM and S-meter data.
read_tx_status(self): reads trasmitter status (transmission power, alc, Vswr and modulation) and store trasmission power in self._t_power, alc in self._t_alc, vsvr in self._t_vswr and modulation in self._t_mod.
get_tx_state_string(self): generates some lines of text which include frequency, modulation, power, alc, vswr and modulation.
read_receiving(self): check if the radio is transmitting or receiving, if it is transmitting return False, if is receiving return True.
write_frequency(self): write a frequency to the radio, the frequency must be a 8 number string, return True if the radio accept the frequency False if the radio cannot set the desired frequency.
write_mode(self): write the radio mode, the radio modes are string: LSB, USB, CW, CWR, AM, FM, DIG and PKT. Return True if the mode is correct and False otherwise.
IF THE RADIO DON'T RESPOND THE LIBRARY QUIT THE PROGRAM!
FT897 class contains the following settings and constants:
SERIAL_SPEED, SERIAL_STOPBITS: COM port speed and stopbits accordingly. By default FT-897 CAT interface is set to 4800 bps with two stop bits.
SERIAL_TIMEOUT: sets COM port reading timeout to avoid program blocking if the transceiver is not connected to the port or is turned off.
Byte sequences to send to the trasceiver to:
CMD_READ_FREQ read frequency
CMD_READ_RX_STATUS: RX status
CMD_SET_FREQ : set frequency
CMD_SET_MODE: set radio mode
CMD_READ_TX_STATUS: TX status
CMD_READ_TX_METER: TX meters
SERIAL_PORT: COM port name where FT-897D transceiver is connected.
SAMPLES_PER_SEC: number of times per second to query the transceiver.
Run the trx_monitor.py file in Python interpreter.
The output consists of lines which are pretty self explanatory.
Starting FT-897D monitor...
Receiving
145237500Hz
FM
SQL: ON
DISCRIMINATOR: NOT CENTERED
CTCSS-DCS: UNDETECTED
S0+00 ...............
Starting FT-897D monitor...
Trasmitting
14523750HZ
FM
Power: 9
Alc: 3
Vswr: 0
Mod: 3
The first line shows frequency, mode (AM, FM, SSB, PKT etc.) and squelch state. The second line is S-Meter which shows S-level and dB over S9 and a simple scale where 15 dots correspond to S0 and 15 pipes correspond to S9+20dB.
You are more than welcome to contact me with any questions, suggestions or propositions regarding this project. You can:
- Visit my QRZ.COM page
- Visit my Facebook profile
- 📧 Write me an email to iosaaris =at= gmail dot com
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