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PLL controller


here is small PCB w/ buttons, standard LCD (HD44780 compatible) connector and microcontroller programmed to send commands to 5055/56 or alike PLL chips. The microcontroller doesn't check PLL status, it just sends command. There are no limits set - you can enter any frequency from 0 to 2999.875MHz, store 8 presets where each channel can be marked to include or skip while scanning , also each channel has it's own timer, that is if your model airplane has two cameras you can set automatic switch say 2seconds for backward looking camera and 10seconds for forward camera.

To install the module disconnect existing wires SDA/SCL from tuner or transmitter module (pins 4,5 ), then solder four wires from the LCD controller. Note: the picture colored wires for demonstration only, the module supplied without any wires.

How to operate: press upper button > channel up, lower button > channel down, hold any button for 2s or longer to start scan, press both buttons to enter setup
While in setup move blinking cursor with upper button, set values with lower button, channels marked "+" incl. in scan.
To exit setup wait till cursor stop blinking

To switch positive/negative offset hold any button while powering up, current offset(+/-480MHz) will be confirmed on LCD.

Use the controller with tuners and transmitters, to program TX calculate current offset and desired frequency.
There are not so many transmitters using TDA5055 chips also most tuners do compatible with the controller.

The controller shipped with female LCD connector, if you want male pins or no connector at all let me know.

some more info/photos posted at

LCD connector

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