Frequency display module
Product code: PLJ
Note: This module is suitable for radios or transmitters with local oscillation loops, but not for DSP radios without local oscillation loops and radios with an intermediate frequency of 465KHZ!
This module is a classic frequency display circuit module, driven by SC3610D, no backlight board, finished module, only need to power up, solder a wire from the Fin foot to the local oscillator loop of the transmitter or radio to display the operating frequency. It is more convenient to use. A powerful tool for adding frequency display to radios or transmitters, the first choice for radio enthusiasts to make frequency meters! Working voltage: 1.8-3.3V, this module currently only supports frequency display, does not support clock function, frequency display range: AM: 0.5-30MHZ, intermediate frequency 455KHZ; FM: 11-150MHZ, for FM, optional intermediate frequency 10.7MHZ(Disconnect IFsel)And 70KHZ(Short IFsel), ModuleThe overall size is 25X24X5mm.
The overall dimensions of the LCD screen are as follows:
Function description of each pin:
1. + pad, the power supply is positive, cannot exceed 3.3V, otherwise the module may be burned out.
2.-Pad, the power supply is negative.
3. Fin pad, external oscillating signal input pin, the board has its own coupling capacitor for the signal under test, no need to connect externally. When used for transmitter frequency display, it is usually connected to the transmitter’s local oscillator output or secondary amplifier output. At this time, the IF should be shorted, and the intermediate frequency 70KHZ should be selected. Whether AF and RG should be shorted depends on actual needs. The displayed frequency has an error of about 0.1MHZ from the actual transmitting frequency; when used for radio frequency display, it is usually connected to the local oscillator output or AFC pin of the radio to display the frequency accurately.
4. AF jumper, AM/FM selection, short circuit---module works in FM display mode, disconnected---module works in AM display mode.
5. RG jumper, when working in FM mode, short-circuit RG, the display frequency range is: 11-150MHZ; disconnect RG, the display frequency range is: 11-99.99MHZ. When working in AM mode, short-circuit RG, the display frequency range is: 0.5MHZ-29.99MHZ, disconnect RG, the display frequency range is: 500KHZ-9999KHZ.
6. IF jumper, FM intermediate frequency selection, short circuit---used for FM radio with an intermediate frequency of 70KHZ(Such as TDA7021, TDA7088, etc.), Disconnected---used for an FM radio with an intermediate frequency of 10.7MHZ(Such as CXA1691, CXA1238, etc.).