The ultimate 6-tubes clockBased on the 4-tubes design (described here), I have created an ultimate 6-tubes nixie clock, and 3 different PCBs.
- One PCB with the tubes in the front
- One PCB with the tubes in the middle
- One PCB with 2 connectors, for socketed tubes
- 4 or 6 tubes
- high-voltage set in software
- tubes with or without decimal point
- each tube gets its own brightness / fading / value
- each tube setting can be set at any 1/64th of a second on a weekly basis...
- multiple effects, such as cross-fading with different speeds, blinking effects, rotate, shift, etc...
- IR receiver (optional)
- DCF77 (optional)
6 clocks have been made, and are running fine for over a year now.
The hardware has evolved from the previous design : double-sided PCB (made by Olimex), as small as possible with through-hole components. The FET is now driven by a dedicated chip, MPC1402 from Microchip. The later takes less space than discrete components, and is even cheaper. The FET remains cold at all time. It's a traditionnal 3x2 multiplex clock, using 2 74141 drivers (actually, their Russian equivalent). The amazing display is obtained by clever software, running in a PIC18. The latest design uses a PIC18F2420, because the 18F2321 was getting too small for the code (all written in assembly for speed and size).