
Nixie Clock
PennyLekas/Nixie-Clock
v1 is broken and required some bodge wires to work. I have not updated the schematic and PCB to correct my mistakes. It also has some deficencies in the dimming circuit resulint in a quiet, but audible whine.

The PZTA42 is a bipolar made by Jiangsu Changjing Electronics Technology (CJ) in a SOT-223 package with 3 pins. -55℃~+150℃ 1 NPN 100nA 1W 200mA 25 300V 500mV 50MHz 6V NPN SOT-223 Bipolar (BJT) ROHS.
PCBKit's library has its KiCad symbol (Transistor_BJT:PZTA42, from KiCad's library) and its footprint (Package_TO_SOT_SMD:SOT-223-3_TabPin2, from KiCad's library), ready for a KiCad board. 6,138 are in stock at JLCPCB (part C148121). 2 open-source boards in 2 repositories on GitHub use it.
| Pin | Name | Type |
|---|---|---|
| 1 | B | Input |
| 2 | C | Passive |
| 3 | E | Passive |

PennyLekas/Nixie-Clock
v1 is broken and required some bodge wires to work. I have not updated the schematic and PCB to correct my mistakes. It also has some deficencies in the dimming circuit resulint in a quiet, but audible whine.

willis936/nixie-clock-ice
Hardware and software source for a GPS nixie tube clock with delay correction.
<iframe src="https://pcbkit.io/embed/parts/cj/PZTA42" title="PZTA42 in PCBKit" width="100%" height="480" style="border:0;border-radius:12px" allow="fullscreen" loading="lazy"></iframe><img src="https://pcbkit.io/embed/parts/cj/PZTA42.jpg" alt="PZTA42" width="1200" height="900">[](https://pcbkit.io/parts/cj/PZTA42)Yes. The symbol is Transistor_BJT:PZTA42 and the footprint Package_TO_SOT_SMD:SOT-223-3_TabPin2, both drawn on this page. PCBKit places them on a board for you when you design with it.
SOT-223, with 3 pins. Its footprint is drawn on this page.
Jiangsu Changjing Electronics Technology (CJ) publishes it: the Datasheet link on this page opens it.
JLCPCB lists it as part C148121, with 6,138 in stock; the sellers' links on this page open their listings.
Parts like it in the library: the PZT2222A by onsemi, the PZTA92 by Jiangsu Changjing Electronics Technology (CJ), the PZT2222A,115 by Nexperia and the BCP51TF by Nexperia. Check their datasheets: a part that fits the footprint may still differ in its ratings.
2 boards in 2 repositories on GitHub; the most starred are listed on this page, with their KiCad files.