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Power - Power is all you need. My circuit setup works well with 9V 400mAh. My fully charged battery managed to drive the esp32-cam in the AP mode for 1hr 35 min.
 The situation is not at all satisfactory when I connect the MB102 to a 12V 1000mA AC/DC adaptor. The esp32-cam as an AP start dropping out of the WiFi it was serving. I have some problems with my power supply, obviously. I may be needing a couple of decoupling capacitors.

I have a few capacitors laying around. I found two 10uF capacitors and they will do for now. I connect one to the MB201 across the 3V3 and GND. The other one across 3V3 and GND of the esp32-cam board.

This result in some stability improvement. The esp32-cam AP service seem to hold stable. Now the live streaming stop after a few frames, the still image web service was ok. Perhaps, I may need a bigger capacitor across the MB201 to compensate for the voltage drop when the esp32-cam demands more power.


The setup works better when running on esp32-cam with station mode.
What have I learned today?
  • Batteries provide a more stable power source then power adaptors.
  • Decoupling capacitors are my friends.
  • AP mode demands more power then STA mode.

I'm now running the esp32-cam with STA mode on a fully charged 9V 400mAh. We will find out how long it will last and compare the finding with the result obtained from yesterday experiment when the esp32-cam was on AP mode.  I'm expecting a longer battery life. How long? You will know tomorrow.

I'm sorry for not being able to conduct more precise experiments. My lab is my kitchen table.

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