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projects:picoatlas:experiments

Experiments

Super Cap Experiments

UKHAS badge board with RFM22, Arduino328 with 8Mhz external crystal (no brownout) running off a 1.8v MCP1700 regulator, 2.5V 10F supercap in parallel to badge board. Charged initially by 3.7v lipo to 1.8v and then this supply is removed either to run off the supercap or the solar panel.

  • 50baud, 1 string every minute, under a lamp indoors
    • Just Cap = 5mins 36secs
    • Solar Cell = 18mins 49secs
  • 300baud, 1 string every minute, under a lamp indoors
    • Just Cap = 12mins 21secs
    • Solar Cell = Continuous

Improvements

  • 2.5v regulator then supercap and then 1.8v reg to the board - this would exploite more of the supercap as we'd get the drop from 2.5v down to 1.6 rather than 1.8 to 1.6v.
  • Boost regulator between supercap and board so we could use all the supercap.
  • Tighter powersaving

Solar APRS

Experiments in the feasibility of solar powered aprs tracker

Components

  • Radiometrix HX-1 300mW 144.800Mhz
  • 2x 2.5 1F supercaps (in series)
  • schokty diode
  • Lipower stepup to 5v
  • The Arduino which is controlling the radio and generating the packet is running off a LiPo seperately.

Circuit

Tests

Saturday 8/12/12

Comment 12/09 09:10 : |("|XX/M6JCX,640
Comment 12/09 09:08 : |(!|XX/M6JCX,639
Comment 12/08 15:21 : |";|XX/M6JCX,119
Comment 12/08 15:19 : |":|XX/M6JCX,118

Its able to restart in the morning and continue transmitting, obviously only sufficient sunlight between 0908 and 1521 to power the radio. This would work a lot better during the summer.

projects/picoatlas/experiments.txt ยท Last modified: 2012/12/18 07:14 by jcoxon