So here is a battery powered power unit for DIY oscilloscope DSO138. It is more complicated than it should be but atleast it works. It looks like a bomb so I gave it a bit decoration by adding matching company name on it.

Jokes aside it uses 2 nine volt batteries as power. My version uses two push buttons and relay for overengineered on/off function. It wastes some amount of power so I also made other version with 13mm x 19mm hole for regular toggle switch. It also has programmable battery voltage display which can be turned off for power saving. I have planned to make rechargeable version in future. I desinged batteries to be held in place by their own holder but they seem to stay in place fine even without it.

Here is list of dimensions of the holes on the lid:
-Battery indicator mounting hole 28.5mm x 59mm
-power button hole d 12.5mm
-Shutdown button hole d 6.2mm
-Alternative version toggle swich hole 13mm x 19mm

And here is list of parts I used:
(sorry that I couldn't add direct links because seller that I used is not avaible anymore. Same products from Alternative sellers can still be found by searching.)
These three are from aliexpress:
-battery meter: "Supnova battery capacity voltage meter 7v-68v dc."
-Power button (not self locking version): "12mm metal push button"
-Stop button (not self locking version): "6mm Mini Momentary Automatic Return Push Button Switch"
These are from local shop:
-Generic small 12 volt relay. (Miniature 9v relay could be better for battery life)
-DC 5.5mm plug and some cables.
-2x 9 volt battery connectors

Felix 2.0

No

Yes

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