The 9V attachable electroscope has been updated. The silkscreened date on the
back for this version is 2014-08-24(!)
- Pulled copper pour near inputs back
- Removed polyimide/kapton shield
- Simplified antennae construction
One slight quirk with nearly all of these electroscopes is that they appear
to be hard ‘on’ after assembly sometimes. In many cases i’ve found that this is
due to residual flux (of the water washable type).
I’ve had success by scrubbing down with isopropyl alcohol and reflowing
again with hot air.
You can find the necessary sources, gerbers, and files here. The BOM is identical to the older version.
The OSHPark shared project for direct fabrication can be found here.
I was able to release a small breakout board based on a sample I received long ago from Texas Instruments.
It is a CR2032 tester, based on the pretty accurate TPS3809L30DBVR part (which was derived
from eevblog’s µCurrent). The LED stops lighting up somewhere slightly at or below 2.64v, where most CR2032 coin cells enter
end-of-life on the discharge curve.
Read more and get it made on the project page.
Nearly a year ago, vk2zay posted a video on electrets. In it, he also shared
a design for a pretty fun electroscope.
As a part of learning KiCAD earlier this year, I turned it into a PCB.
This is the latest result:
The exposed copper area accepts a combination of kapton+sticky copper tape+kapton for some rudimentary shielding. LEDs are 3mm, or
0805 (imperial). The antennae are simply stripped breadboarding wire.
It triggers on things I would have never expected.. like the clear plastic bags some components come in (from a
very popular electronics vendor in the middle of nowhere). With the right LEDs (non-diffused/surface mount), people shuffling by light it up,
and many are curious enough to pick it up and play with it/ask questions.
You can get your own copy of the PCB through the OSHPark shared project page, or grab the source
KiCAD files/Bill of Materials/Placement here. If you want the Gerbers used in fabrication, OSHPark has started
exposing those as well, here.