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• Transmission working !!!!!!!!!!!!!!!!!!!!!!!!

  bobricius • 07/13/2018 at 22:40 • 0 comments

  After hours/days of debugging and tuning I have working reliable transmission.

  Some facts:

  Transmission time for 16bit data with 1200bps is 34ms with all sync and receiver tuning bites

  Harvester features:

  Key timing component is middle capacitor, and there is some power facts
  As load is connected Attiny85/1Mz with running code (no sleep) without transmitter

  Power supply length

  • 100n = 15ms run-time every 1s
  • 1uF = 17ms run time every 13s
  • 10uF = 35ms every 60s

  I have now reliable transmission for 16bit value every 30minutes, It is little long time but I am on beginning
  with this project.

  Without load is power supply pulse 60ms long every 60s 

• Harvester demonstrator & test board half assembled

  bobricius • 07/04/2018 at 22:31 • 0 comments

  Yes, finally boards are home. All working good :)

• Harvester demonstrator

  bobricius • 06/27/2018 at 21:52 • 0 comments

  I finished harvester demonstrator with wireless transmitter and Attiny85

  Solar array is large but I have plan to use only 4 diodes.

• dirty run time check ... is 150uS enough ???

  bobricius • 06/21/2018 at 21:36 • 0 comments

  I try charge pump with attiny85 1Mhz

  digitalWrite(LED,HIGH);
  delayMicroseconds(1);
  digitalWrite(LED,LOW);
  delayMicroseconds(150); // runtime delay
  digitalWrite(LED2,HIGH);
  delayMicroseconds(10);
  digitalWrite(LED2,LOW);

  With dirty trial and error experiments I adjusted, maximum run time is 150uS with 1Hz repeating 

  Of course there is lot of possibilities to charge additional capacitor but unfortunately voltage rising very very slow and micro-controller can not start.

  I think 150us is enough to send very short maybe 8bit packet with simple 433Mhz ASK/OOK radio

  Success for 4 small diode power supply

  It is time do design first more complex board :)

• Prototype testing board

  bobricius • 06/12/2018 at 20:32 • 0 comments

  After breadboard success I designed first application .... flashing heart, first batch was just only garbage due mistake in design.
  

• Harvesting test

  bobricius • 06/12/2018 at 20:26 • 0 comments

  As you can see on first video, led flashing in room light.

  Power output is short 2V pulse.

  I created all on breadboard and about month experimentally adjust components values to get best performance.

  Charge pump schematic.

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