DIY kit AT89C2051electronic clock digital tube LED display kit electronic module

feature: Power supply voltage: DC 5 - 12V (above 7V the four LED lights in the middle are on) Recommended voltage: DC 9V Working current: 35mA (external power supply self-provided) Standby current: 1.2 MA (powered by backup battery) Backup battery: CR2032 (3V) Plate size: 90mm * 65mm Specification: The kit uses three two-digit digital tubes to display the hours minutes and seconds of the time and two small LEDs instead of colons to indicate time intervals. It adopts single-chip microcomputer programming control display adopts timer timing high precision -key time adjustment and has memory battery the main power-off time is still running (digital tube does not display). This is practical. Product Description_ 1. 89C2051 digital clock group the control chip adopts AT89C2051 the digital tube adopts three two-red common positive LED digital tubes the display is clear and the brightness is high because it is a scanning display mode so the ABCDEFG pin of each digital tube is connected in parallel with the bus changing The resistance value of r4-r10 can change the display brightness. 2. The S1 button is used to calibrate the time. Press and hold for more than 2 seconds to enter the calibration time state and exit. A quick touch is used to adjust the time value. 3. A 3V backup battery has been added to the circuit. When power is lost the AT89C2051 is powered by a backup battery. The clock didn t stop but the nixie tube didn t show. Battery backup for incoming calls will not work. AT89C2051 uses an external power supply and the digital tube displays normally. So you can add a power switch turn off the power when you go out and make a call when you come back you can display it normally and save power. 4. The departure time is accurate. Notice_ _ If the nixie tube displays abnormally please disconnect the power supply take out the spare battery and then reinstall it. It will return to normal after power on. If you use the main power supply for a long time please remove the R1 resistor that is the R1 resistor cannot be welded. The existence of the R1 resistor will charge the battery and the long-term power supply will continue to charge the battery. This is a non-rechargeable battery that will damage the battery and cause it to not function properly. Occasionally power on for a short time the display time can be soldered to R1 and occasionally the battery is charged to maintain power. Package includes: 1 set of LED display kit