Ham Radio Remote Control Radio Interface
This post is about building a ham radio remote control radio interface to remotely operate non-CAT-controlled amateur ham radio transceivers with a Raspberry Pi and ham radio remote control software.
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Functions:
- Turn radio power On/Off
- Toggle Push to Talk (PTT)
- User-selectable GPIO pins
- Route Speaker-Microphone Audio between the USB Audio adapter and the Radio
Prototype Circuit Development
Schematic
Click image to enlarge
Prototype Printed Circuit Board (PCB)
PCB Layout
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Working Prototype
Icom IC 2AT
IC 2AT - Ham Radio Remote Control Radio Interface - USB Audio adapter - Raspberry Pi
Notes:
This project still in the experimental stage...
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Jumpers J1-J7 custom PTT options:
- J1-J2 Transistor IC 2ATPTT
- J2-J4 Transistor PTT
- J3-J5 Relay PTT
- jumper J3-J4 for PTT RLY 1
GPIO pins user-selectable.
Simple Ham Radio Remote Control IC 2AT Configuration:
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Jumpers J1-J7:
- J1 - J2 installed for IC 2AT PTT
- All other jumpers open
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GPIO # - Pin #:
- Power On/Off GPIO 23-16
- Push to Talk GPIO 24-18
- Ground pin 14
Keep the Raspberry Pi, Speaker - Microphone Audio grounds isolated from each other.
Note: GPIO pins are user-selectable pins assigned on the schematic and printed circuit board were just used for testing..
USB Audio Adapter Example
Icom - Yaesu Radio Audio Interface Example
Click image to enlarge
USB Serial to Icom CI-V Interface Example
To remote control older Icom radio you need a USB serial to Icom CI-V Interface Here ✓
Click image to enlarge
Note: To use this CI-V interface with the IC 2730, replace the 3.5mm mono plug with a 3.5mm stereo plug then connect the Tip to the Ring.
I have used this RS232 to Icom CI-V interface for many year it simple and it works, but I replaced the 2N2222 with a 2N3904.
I also use the Icom CT-17 CI-V Level Converter (no longer available from Icom)
USB Serial Adapter Example
This table shows the pin numbers with signal names and the signal direction.
| Pin | Signal | Signal Name | DTE Signal direction |
|---|---|---|---|
| 1 | DCD | Data Carrier Detect | In |
| 2 | RXD | Receive Data | In |
| 3 | TXD | Transmit Data | Out |
| 4 | DTR | Data Terminal Ready | Out |
| 5 | GND | Ground | - |
| 6 | DSR | Data Set Ready | In |
| 7 | RTS | Request to Send | Out |
| 8 | CTS | Clear to Send | In |
| 9 | RI | Ring Indicator | In |
The Icom CI-V interface is powered by pin 6 DTR by default DTR is set Low so it needs to be set High using the following command:
stty -F /dev/ttyUSB0 -hupcl
Or replacing /dev/ttyUSB0 with whatever device file actually corresponds to your USB serial port.
Note: This will have to be set every time the Raspberry Pi is turned ON.
Make sure that the Radio - Software baud rate is the same, then plug the 3.5mm mono plug into the radio CI-V port and your ready to go...
Power Module to Turn Older Radios ON/OFF Example
Older CAT capable radio without a command to turn the radio ON/OFF remotely require an external power interface.
The relay should be a High Current 12V Contactor relay to Switch DC power
Click image to enlarge
Note: this circuit can also be used for the push-to-talk (PTT) relay.
Related Links
¹ CI-V stands for Computer Interface 5 [Roman numeral "V"]
² CAT stands for Computer Aided Transceiver