Hi, the formula for calculating DC power is P=UI, where U is supplied voltage, I is circuit current, so, your math is correct, 9V power supply, with 200mA gives you 1.8W of power. Multiply the result with (h) to het Wh (and divide by 1000 to get kWh). Hope this helps.
@@asquicklyaspossibleyou mentioned at 1:06, in the power requirements, DSO138 needs Atleast 18 watt. This confused me. Any way I watched your videos mostly. Very helpful.
Hi, thank you for your question. Since there is no on/off switch on board itself, unplugging DC power supply has the same effect as removing battery - it turns off the board. Only way is to implement mechanical switch between battery and board, so that you don't have to remove battery every time you want to turn off the oscilloscope. Adding a on/off switch directly on board would be an interesting DYI project. Again, thank you very much for your question and we wish you all the best.
@@asquicklyaspossible thank you so much for fast reply. i didnt risk to add switch on the pcb, specially that i assembled acrylic case. so i hot glued 9v battery holder on the right side of case also glued toggle on off switch and used 9v rechargeable liion battery. thanks so much also coz your instructions was very useful in assembling acrylic case.
using a cheap boost converter and a 3.7V Li-Ion battery gives me only 3mV 16kHz square wave noise. I can live with that and enjoy not producing unneccessary waste.
9V at 200mAh this might be 1.8 watt. Help this. Thanks in advance
Hi, the formula for calculating DC power is P=UI, where U is supplied voltage, I is circuit current, so, your math is correct, 9V power supply, with 200mA gives you 1.8W of power. Multiply the result with (h) to het Wh (and divide by 1000 to get kWh). Hope this helps.
@@asquicklyaspossibleyou mentioned at 1:06, in the power requirements, DSO138 needs Atleast 18 watt. This confused me. Any way I watched your videos mostly. Very helpful.
if we use battery is there any option to on and off without disconnecting battery?
Hi, thank you for your question. Since there is no on/off switch on board itself, unplugging DC power supply has the same effect as removing battery - it turns off the board. Only way is to implement mechanical switch between battery and board, so that you don't have to remove battery every time you want to turn off the oscilloscope. Adding a on/off switch directly on board would be an interesting DYI project. Again, thank you very much for your question and we wish you all the best.
@@asquicklyaspossible thank you so much for fast reply. i didnt risk to add switch on the pcb, specially that i assembled acrylic case. so i hot glued 9v battery holder on the right side of case also glued toggle on off switch and used 9v rechargeable liion battery. thanks so much also coz your instructions was very useful in assembling acrylic case.
Rechargeable batteries would be great
We agree 👍
using a cheap boost converter and a 3.7V Li-Ion battery gives me only 3mV 16kHz square wave noise. I can live with that and enjoy not producing unneccessary waste.
How about 3 of 3.7v Li-Ion and step down converter?
or 3 of 3.7v to 7809 IC ?
9 times 0.2 is 1.8, not 18