wiki:NixieClock

Version 18 (modified by Eric Hazen, 4 years ago) (diff)

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http://ohm.bu.edu/~hazen/Nixie/New2019/mainboard.jpg

http://ohm.bu.edu/~hazen/Nixie/New2019/socket_board.jpg

PCB holding two IN-12B (B-5991) nixie plus two neons for optional colon. Pins for D sub connectors fit well but are realatively expensive except for crimp ones.

New PCB done in 2018 in SVN above with ATTiny861A. Parts kit and PCBs in stock. Designed ATTiny861A which unfortunately doesn't have asynchronous serial either, but at least has 512 bytes of RAM so can be programmed in C. Seems like an ATTiny2313 with serial port could be used too.

9600 * 8 =~ 1MHz / 13 so we could use the 1MHz default oscillator as an 8x baud clock for 9600.

2020-06-07

Time to finish this thing! Moved doco to github. Wired an ESP8266 to get the time from wifi, and added support in the AVR code. Now just need to figure out a 5V supply solution and get it in a box.

Nixies seem a bit bright. Power supply measures DC 157V (100VAC at input through Triad N68X. 20V across 10k cathode resistors (2mA). According to ​IN-12A data this is fine, so never mind.

2020-03-02

New nixie socket board works!

Looking at 60Hz input. Layout has a mistake... missing via under pin 2 of C4. Added a wire. No signal downstream of C4 (ratty 300mV). Not sure what the plan was with D4. Should be between GND and VCC. Could cut the trace to D4 pin 2 and wire to VCC. Tried this, no better. Need to redesign this.

2020-02-09

Verified that the board works (drives two Nixies), but with some issues:

  • Tens and Ones digits reversed.
  • Nixies too close together
  • Spun a Rev B of the socket board and ordered from Osh park today

ECOs

  • Change 10 pin ISP for 6 pin

Debug Log