Crt Clock Schematic › | RECENT |

                   +15V        +170V        +12V
                    |           |            |
    AC IN -> Bridge -> 7805 -> MCU (Arduino)
                |-> Boost SMPS -> HV (1.2kV)
                |-> 555 timer -> Z-axis driver

MCU PWM1 -> DAC X -> X-amp -> Horizontal Deflection Plate
MCU PWM2 -> DAC Y -> Y-amp -> Vertical Deflection Plate
MCU Digital Out -> Transistor -> CRT Grid (Z)
RTC (DS3231) -- I2C -- MCU

In an age dominated by silent, flat-panel displays and voice-activated smart devices, the warm, glowing flicker of a cathode ray tube (CRT) seems like a relic from a bygone era. Yet, for a niche community of engineers, hobbyists, and retro-computing enthusiasts, the CRT remains a medium of fascination. One of the most compelling projects that bridges the gap between obsolete hardware and functional art is the CRT Clock. Examining the schematic of a CRT clock reveals not just a method of telling time, but a masterclass in analog circuit design, high-voltage safety, and the innovative repurposing of electrostatic deflection. Crt Clock Schematic

Use a high-voltage op-amp like the APEX PA94 (expensive) or a discrete design using 2N5401/2N5551 transistors. +15V +170V +12V | | | AC IN

X-Axis Circuit:

  • Feedback: Resistor network (100k:1k) for gain of ~20x.

    • Alternative (Magnetic Deflection): If using a salvaged CRT from a portable TV, the schematic requires a TDA1170 vertical IC and a horizontal driver via a yoke. This is not recommended for novice clock builders due to linearity issues. In an age dominated by silent, flat-panel displays