====== 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 ==== {{:projects:picoatlas:aprscircuit.png|}} ==== 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.