AMYTICKER - High-Performance TICK Module for Amiga 2000 & 3000

The AMYTICKER is a purpose-built, high-performance module designed to generate precise clock and timing signals for classic Amiga 2000 and 3000 computers. Engineered with system stability and TICK synchronization in mind, it's perfect for enthusiasts looking to maximize performance when using an ATX power supply unit (PSU) that provides standard outputs of +5VDC, +12VDC, and -12VDC.

Key Features:

• Crystal Oscillator: Calibrated to support both PAL (3,276,800 Hz) and NTSC (3,932,160 Hz) standards, ensuring accurate timing signals for seamless TICK synchronization.
• Advanced Logic ICs:
  • A 74HC00AP quad NAND gate processes the base frequency.
  • A 74HC7292AP high-speed CMOS programmable divider/timer divides the frequency for precise output control.
• Voltage Regulation: Equipped with an LM2940CT-5.0 voltage regulator, providing a clean and stable -5VDC output derived from the -12VDC supplied by an ATX PSU.
• Convenient Connectivity: A 5-pin terminal block offers labeled connections for +5V, GND, -12V, -5V, and the dedicated TICK output signal.
• Diagnostics Made Easy: The reverse side of the PCB includes five clearly labeled test points (TP1 through TP5), each providing specific frequency divisions of the main oscillator (e.g., /512, /8, /1024, full frequency, /65536). These test points are invaluable for troubleshooting and integration.

Professional Design:

The AMYTICKER is built on a professionally fabricated PCB with a sleek black solder mask and clear silkscreen labeling for all components and connections. This attention to detail ensures ease of installation and long-term reliability.

Why Choose the AMYTICKER?

This module is brand new, in excellent condition, and ready for immediate installation. It resolves common TICK synchronization issues and provides the missing -5VDC voltage required for optimal operation of your Amiga system. Whether you're restoring a classic machine or upgrading its capabilities, the AMYTICKER is the perfect solution for achieving rock-solid stability and precision.

How to Connect the AMYTICKER to Your Amiga

1. Power Input: From ATX PSU to AMYTICKER

The AMYTICKER requires only three connections from your ATX power supply:

• +5V (Red wire): Powers the logic circuitry on the AMYTICKER.
• GND (Black wire): Ground reference for all signals.
• -12V (Blue wire): Used by the onboard voltage regulator to generate -5V for the Amiga.

These wires connect to the 5-pin terminal block on the AMYTICKER board:

• +5V → Pin labeled “+5V”
• GND → Pin labeled “GND”
• -12V → Pin labeled “-12V”

Note: The other two pins (“-5V” and “TICK”) are outputs, not inputs.

2. What the AMYTICKER Does

Once powered, the AMYTICKER performs two critical functions:

A. Generates -5VDC

Many classic Amigas (especially A2000/A3000) require -5V for proper operation of their clock/timing circuits — but modern ATX PSUs no longer provide this voltage.

The AMYTICKER uses an LM2940CT-5.0 voltage regulator to convert the incoming -12V into a clean, stable -5V, which is output via the “-5V” pin.

B. Generates a Precise TICK Signal

The TICK signal is a timing pulse required by the Amiga’s custom chips (Agnus/Alf) to synchronize internal operations. Without it, you may experience boot issues, flickering video, or crashes.

The AMYTICKER uses a crystal oscillator (either 3.2768 MHz for PAL or 3.93216 MHz for NTSC) and logic ICs to generate a perfect, synchronized TICK signal — output via the “TICK” pin.

3. Outputs to Power Up the Amiga

From the AMYTICKER’s terminal block, you take these five outputs and connect them to your Amiga’s main power connector:

• +5V: Already supplied by the ATX PSU → Connect to Amiga’s +5V rail.
• GND: Common ground → Connect to Amiga’s GND.
• -12V: Pass-through from ATX PSU → Connect to Amiga’s -12V rail.
• -5V: Generated by AMYTICKER → Connect to Amiga’s -5V rail (often missing with ATX PSUs).
• TICK: Generated by AMYTICKER → Connect to the Amiga’s TICK input pin (usually pin 1 or 2 on the power connector).

Also shown in the diagram:

• +12V (Yellow wire): Comes directly from the ATX PSU → Goes straight to the Amiga’s +12V rail.
• Additional +5V lines (Red wires): Also from ATX PSU → Go to Amiga’s +5V rails (multiple connections often needed for stability).

Why This Setup Works So Well

Modern ATX PSUs are great for providing +5V, +12V, and GND — but they lack -5V and TICK. That’s why many Amiga retro-builds fail or behave erratically when using them.

The AMYTICKER solves both problems:

• It generates the missing -5V from -12V.
• It generates a rock-solid TICK signal from a crystal oscillator.

This makes it ideal for anyone upgrading their Amiga with a modern ATX PSU — especially for A2000/A3000 users who want reliability without modifying the original motherboard.

Quick Installation Summary

1. Connect +5V, GND, -12V from ATX PSU → AMYTICKER terminal block.
2. Connect -5V, TICK, +5V, GND, -12V from AMYTICKER → Amiga power connector.
3. Connect +12V, +5V from ATX PSU → Amiga power connector (bypassing AMYTICKER).
4. Power on — enjoy a stable, fully functional Amiga!

In short: The AMYTICKER bridges the gap between modern ATX PSUs and classic Amiga hardware by generating the missing -5V and TICK signal — making your retro build reliable and plug-and-play.