Art and Technology are Friends

Posts tagged “Project

Pocket High Voltage Generator Quick Build

Pocket HV Generator

- There’s an update to this post, including PCB design files. -

There are times you find yourself looking for a relatively high voltage (100V to 200V often in my case) but low current DC power supply. I have zener diodes that are higher than 30V, which makes the lab supply useless, and filament LEDs with forward voltage over 60V. When I need to test them quickly, I used to hook up a simple rectifier circuit to a variable AC power supply (nothing more than a slidac with isolation transformer). While this gets job done, the setup is capable of supplying much too high current (1A or more), so I was always very nervous and extra careful in handling the circuit. All I need is a little HV generator that gives me around 200V DC and only capable of supplying a milliamp or less. Realizing that I do have such design available – one of the Nixie supply circuit – I just decided to put one together to use.

Pocket HV Generator schematics

Quick & dirty build of the tool.

Quick & dirty build of the tool.

A single AA battery seems to be enough to generate over 200V on the output with no load. But the output quickly lowers when you draw 0.4mA. So it feels pretty safe to handle this casually, and I can only feel a bit of tingling, not electric shock when I touch the output terminals. The tool proved to be quite handy and useful in testing variety of things:

  • Zener diodes (zener voltage)
  • Switching diodes (reverse breakdown voltage)
  • Filament LEDs (forward voltage)
  • Regular LEDs (forward voltage – yes it’s ok to use this tool, since it’ll only give less than 1mA even at 2-3V)
  • BJTs (breakdown voltages)
  • Neon & Nixie tubes (not very bright, but you can tell if one works or not)
Pocket HV Generator testing a zener diode

Pocket HV Generator testing a zener diode

Pocket HV Generator testing a Nixie tube

Pocket HV Generator testing a Nixie tube

This is one of the most useful tools that I’ve made. And it only took a couple of hours to put it together.

Audio Interface for Aurora – Through-hole version

Aurora Audio Interface Through-hole version

This Interface turns Aurora 9×18 mk2, Aurora 18×18 or Aurora 12 bar into the ultimate color organ. This is the through-hole only version of the same exact circuit as the original Audio Interface.

Some Old Works of Mine

I was doing some clean up and found some old works from years ago…


The First batch of New Aurora Shipped

Many thanks to your support, the first batch of the new Aurora kits shipped out yesterday. There are a few more orders left to ship, however due to the shortage of a part (sorry I did not expect to run out of parts) the rest of orders will have to ship next Tuesday.

I will be updating my instructables to include new firmware, but meanwhile here are the files you need to program the PICs on the new Aurora’s.

There are also online version of the “Part Placement Guides”.

Audio Interface for Aurora

Aurora Audio Interface closeup

This Audio Interface turns Aurora 9×18 mk2 and Aurora 18×18 and Aurora 12 bar into the ultimate color organs.

Aurora 18×18 Final Preview

Here are some pictures of the final version of Aurora 18×18. Production PCBs will be here in 2 weeks time, and I will start shipping the kits as soon as I have the PCBs.

Interested in building one? See here for the pre-order deal.

Aurora 9×18 mk2 sneak preview

The “new & improved” version of Aurora 9×18 is almost ready to be released.

The overall dimension (4.3 inch diameter), LED layout, PWM capabilities are all exactly the same as the original. However the PIC microcontroller has been replaced with a newer one (PIC24FV16KA301), which simplifies the driver circuit a bit. The new version also has an IR (Infra-red) remote receiver, so you can control it via any universal (or Sony TV) remote controllers.

There is another, new function that adds new excitement to Aurora – audio interface. With an optional Audio Interface (will be available as a separate option), you can connect Aurora 9×18 mk2 to any audio sources. Aurora 9×18 mk2 will then give whole new dimension to your music listening experience.

Photos and video of the working prototype will be posted very soon…

The original Aurora 9x18

Now I need your help to bring Aurora 9×18 mk2 into self assemble kits like other Aurora’s. In order to do that I need a small capital to start the production of PCBs, etc. So I’m offering a “pre-order” deal to speed things along.

Please view the post here about the pre-order deal. Hope you can help.

Aurora mini 18

Aurora mini 18 is only 2 inches in diameter, yet controls 18 full-color (RGB) LEDs individually. The technology that enables this little thing is as amazing as the lights it produces.

Please review the instructables before purchase – assembly requires soldering skill. You will also need PIC programmer such as PICKit 3, ICD 2, ICD 3 (PICKit 2 doesn’t work with the PIC used). If you don’t have a programmer, you can purchase the PIC programmed with the latest firmware. (The PIC will be soldered to the PCB)

- Detailed technical information at

- Aurora mini 18 part placement chart (PDF)

* Firmware update – download here *

*** Purchase Here ***

Two LED Blinky