The Z565M is a neon-filled decadic display tube manufactured by RFT in East Germany. Although it resembles a Dekatron, it lacks any kind of counting capability. Unlike the ZM1050/Z550M, it also cannot be controlled using logic-level signals. Instead, it operates more like a regular Nixie tube and is soemtimes referred to as a “Register tube”.
It features ten wire-formed cathodes arranged in a circle around a common anode. One or more cathodes can be ignited by connecting them to ground. When viewed from the front, the tube shows two empty holes between each cathode. In a full Dekatron tube, these positions would have been occupied by the transfer electrodes. To ensure consistent ignition regardless of ambient light or background radiation, the Z565M includes a small amount of radioactive material to improve the rate of spontaneous ionization of the neon gas.
The tube was specifically intended for use in Dekatron-based counting circuits where it would have been a visually compatible display component. Similar tubes include the GR10A and Z503M.
Key Specifications
| Property | Description |
|---|---|
| Manufacturer | RFT |
| Time period | Late 1960s |
| Envelope diameter | 30mm |
| Envelope height | 53mm |
| Socket | B13B |
References
