The GC12/4B is a neon-filled counting tube manufactured by ETL in Great Britain, capable of bi-directional operation and up to 4,000 counts per second. It features twelve stable cathodes, unlike the usual ten found in most Dekatrons, allowing it to count in base-12. Four of these cathodes are connected to output pins, enabling them to trigger actions such as advancing another Dekatron when active. Divide-by-12 Dekatrons like the GC12/4B were ideal for timekeeping applications since the division of hours, minutes, and seconds in a day aligns with multiples of twelve.
The GC12/4B is nearly identical to the GC10/4B, with the key distinction being that the latter has only the standard ten stable positions.
Key Specifications
| Property | Description |
|---|---|
| Manufacturer | ETL |
| Time period | ? |
| Filling | Neon |
| Counting speed | <4,000 c/s |
| Envelope diameter | 29.5mm |
| Socket | K8A |
References
Like many of ETL’s tubes, the GC12/4B comes packaged with a rocket-shaped cardboard insert that securely holds the tube inside the box.