10002 Zen


At some point I though about building the smallest PCB for a sensor node that I could. Hence, the ZEN was born. The PCB is small enough to fit on a holder of 2 AA batteries.


I have only build a few of these. Here is one reading the soil moisture sensor on basil.

Here is another one chilling in the fridge, reading a temperature sensor.

And here is one replacing the alarm on a door sensor, so it becomes the door sensor. I thought these would look better, but the quality of the casing leaves a lot to be desired, hence I will not use them anymore and will probably 3D print a case on my new 3D printer.

Is it useful?

So far the only case where the small size mattered is for the door alarm, where I wanted a PCB to fit in the original device, but there is not need to do that. Generally, I prefer the normal type where the PCB is under the battery more. There is more space for connections and the PCB design is faster.

Now, I never found an application where I needed a very very small sensor, something that will be powered by a coin cell around the house…

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  1. Pingback: 10002 Screens and controls – Electro Bob

  2. Is it useful? NO, I losted my time to read your useless project…

  3. Pingback: 1000² Zen – gStore

  4. Hello Bob, I find Your home automation project really inspirational. I have seen your summary on software and hardware and I am wondering if You are posting Your boards and software design somewhere? Do You consider open software/hardware or selling your boards somewhere (i.e. Tindie). I thought about home automation myself and would not want to reinvent something which have done so well.
    Best regards,

  5. Pingback: The basil speaks to me – Electro Bob

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