Note: a clear see-through cover might not be ideal for our application, as sunlight might cause too much heating in this configuration. More convenient might be a plastic cover that can be opened easily.
Possibilities:
Datasheet for sensors: https://maxbotix.com/pages/hrxl-maxsonar-wr-datasheet
Looks like the resistor I'm using triggers a send every 3 minutes. Going to try to aim for more like 10 minutes, or even 20 minutes.
If we consider that the 'wake' voltage is about 40 mA, we can calculate how much current is being used for how long.
If the battery is 1000 mAh, and we're awake (because of a bug) for 10 minutes @ 40mA, then we're burning 40% of the battery energy right there ...
But every 'wakeup' also burns battery for some amount of time.
There's a simple optimization problem here.
Bang on! Very solid timing of the satellite monitor.
Battery charge seems to go to max immediately, then fluctuate by a large amount in the sun ... but, baseline is clearly rising.
via http://bayou.pvos.org/data/35tmkbqumaz7?plot_param=battery_volts
One issue: should have the resistor TPL5110 choice such that the wake interval is greater than the maximum awake interval if all satellite attempts are tried ...
Note that it looks as overnight, with full view of sky and away from house, we sent on first try.
via http://bayou.pvos.org/data/35tmkbqumaz7?plot_param=aux_3
Sensor comparison chart:
Via https://cdn.shopify.com/s/files/1/0550/8091/0899/files/HRXL-MaxSonar-WR_Datasheet.pdf
https://learn.adafruit.com/circuitpython-display-support-using-displayio/text
https://www.reddit.com/r/circuitpython/comments/jp10d1/is_there_a_bdf_font_repo_somewhere/
https://github.com/olikraus/u8g2/tree/master/tools/font/bdf
via https://maxbotix.com/pages/xl-tanksensor-wr-datasheet
via [file:///home/db/Downloads/PD11838z_-XL-MaxSonar-WR_Datasheet-website.pdf](file:///home/db/Downloads/PD11838z_-XL-MaxSonar-WR_Datasheet-website.pdf)
http://159.65.226.222:4000
digitalocean edgecollective
iridium-bayou-relay
pubkey: 2ifhwi34ue4j
link for lora data: http://bayou.pvos.org/data/35tmkbqumaz7?plot_param=battery_volts&limit=10
new link for satellite data: http://bayou.pvos.org/data/gcr565avyan2?plot_param=battery_volts&limit=10
Note: solution to blinking TPL5110 problem was to add a 1000 uF cap across GND + DRIVE on the TPL5110, likely due to the initial current draw from the ESP32
For now, should probably place it on the underside of the board so that it doesn't get jostled when pressing the button
Quick notes on upgrades before mailing prototype:
Currently $0.18 per credit.
Currently every 3 hours = 8 credits per day.
I.e.: $43 per month