27MHz radio control
plus telemetry option
This future project is based on the 27MHz remote control system mentioned elsewhere on this website with the option for telemetry added. One antenna is used for both transmitting and receiving. The radio part is based on the AX5043 transceiver with which a half-duplex radio link is established. The following data will be transmitted to shore at a rate of about 5Hz: ​
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Error status
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Vessel configuration
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Vessel motion (H+V)
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Depth and battery voltage
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Speed and pitch (3D accelerometer)
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Piston position and the status of piston tank end-limit sensors
Piston tanks equiped with a sliding potentiometer or HALL sensor can be used for feedback of the piston position.
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An absolute 5V pressure sensor with a differential output and an offset input can also be connected to the backplane PCB. The offset is used for atmospheric pressure compensation.
The PCB assembly has been optimised for installation in the Patrick Henry model submarine. To facilitate electrical connections, all connectors are located on one side of the backplane PCB. The surface area of the backplane PCB is 60 x 100 mm. The height of the backplane PCB with plug-in PCBs is 70 mm. The front plug-in PCB contains voltage regulation circuitry, the mid the micro-controller and the rear the radio.
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The antenna in the model submarine is a shortened isolated wire dipole antenna for use inside the watertight compartment of a model submarine. It is optimised (dielectric constant) for mounting against/on the plastic material of the watertight compartment. The two dipole elements (330mm wires) are soldered on a small impedance matching PCB that amongst others provides galvanic isolation (MABA-11040). The antenna has been successfully tested for receiving and transmitting purposes and is also used as receive antenna in the non-telemetry RC option.