Crt Clock Schematic

flowchart TD subgraph Power_Supplies["Power Supplies"] PS_HV["High Voltage Supply<br>(e.g., DC-DC Boost)"] PS_HT["Filament & Bias<br>(e.g., 6.3V, ±12V)"] end subgraph Signal_Processing["Signal Processing"] MCU["Microcontroller<br>(e.g., ESP32, PIC16F876)<br>Generates X, Y, Z Signals"] DAC["Digital-to-Analog Converter<br>(Optional, for high precision)"] RTC["Real-Time Clock<br>(e.g., DS3231)"] end

Z_OFF(); // Move to next digit with beam off

At the input side of the schematic, one finds a conventional timekeeping source. This is typically a microcontroller (like an Arduino or PIC) or a dedicated real-time clock (RTC) chip connected to a 32.768 kHz crystal oscillator. This low-voltage digital section generates the raw data: hours, minutes, and seconds.

The schematic follows a "vector" display logic rather than a "raster" scan.

must pull it. This keeps the average voltage in the center of the tube stable, preventing the focus from blurring. The Z-Axis (Blanking) Circuit Crt Clock Schematic

Cathode-Ray Tube (CRT) clocks represent a fascinating intersection of mid-century display technology and modern digital timekeeping. Unlike standard LED or LCD clocks, a CRT clock uses an electron gun to paint time digits directly onto a phosphor-coated screen.

A —often referred to as an "oscilloscope clock"—is a unique timepiece that uses a vintage vacuum tube to display the time through vector graphics. Unlike standard digital clocks that use LEDs or LCDs, a CRT clock uses an electron beam to "draw" numbers and clock faces directly onto a phosphor-coated screen.

: These circuits control the horizontal (X) and vertical (Y) plates of the CRT. Schematics often use dedicated tubes like the EF80 or high-voltage transistors (like the STP2NK90Z ) to amplify low-voltage signals into the hundreds of volts needed to move the electron beam.

, where voltage applied to internal metal plates moves an electron beam to "draw" the clock face. Core Circuit Blocks The schematic follows a "vector" display logic rather

Operating and testing a CRT clock schematic involves lethal voltages. High-voltage capacitors can hold an electrical charge for days after power has been disconnected.

The control grid (G1) sits at a negative bias relative to the cathode (usually -30V to -100V) to control brightness. The focus grid (G2) requires an adjustable voltage, often around +200V to +500V, to sharpen the beam spot.

Working with high-voltage electronics requires strict adherence to safety protocols.

Maintain a minimum clearance of 2.5mm per 1000V between high-voltage traces and low-voltage digital components. Use isolation slots (physical routing cuts in the PCB) underneath the high-voltage sections. The Z-Axis (Blanking) Circuit Cathode-Ray Tube (CRT) clocks

(e.g., Arduino, ESP32, AVR) Handles timekeeping and calculates vector points for numbers.

Do you prefer or electrostatic deflection ?

Converts digital coordinates into X and Y analog voltages.