Edge Collective

35. Miscellaneous projects

Broken wire detection, trailer, pc fan filter, DIY boots

Broken wire detection

$35 Tone generator kit

PC Fan filter box

https://itsairborne.com/the-mini-pc-fan-cr-box-975d0b069f4c

Nice build instructions for 20" setup, with evaluation by Rob Wissman for different configurations:

https://itsairborne.com/building-a-pc-fan-corsi-rosenthal-box-68e7cd1ca570

-- seems as though 6 fans on opposite sides, or above and side, get about 280 CADR (cfm)

Comparing performance of box fan and pc fan filter boxes:

https://www.texairfilters.com/comparing-the-performance-of-corsi-rosenthal-boxes-made-with-box-fans-and-pc-fans/#:~:text=To%20check%20the%20%E2%80%9Cthrow%E2%80%9D%20factor,to%20%E2%80%9Cdistribute%E2%80%9D%20the%20air.

luggables https://www.cleanairkits.com/products/luggables

CADR of 500 CFM:

Other articles by Joey Fox: https://itsairborne.com/building-a-pc-fan-air-purifier-using-filterboxbuilder-com-8075bfbd6b4c

Foam weatherstripping https://www.amazon.ca/s?k=1%2F8+Inch+Thick+Weather+Stripping+Foam&i=industrial&crid=3QWSJMQNCS8J4&sprefix=1%2F8+inch+thick+weather+stripping+foam%2Cindustrial%2C131&ref=nb_sb_noss

Thu 12 Dec 2024 09:27:10 PM EST

Trailer design

Mon Dec 30 07:20:23 PM EST 2024

Nice example of trailer frame framing and paneling and rubber roof and first trip

note: the sides are aluminium sheeting

PC Fans

Delta 120mm Noctua NF-F12 3000rpm 109.8 CFM at mo

Which fan to get for a corsi box: https://www.reddit.com/r/Masks4All/comments/vyeln8/which_fan_to_get_for_a_mini_corsirosenthal_box/

assessment of corsi with single filter: https://x.com/DavidElfstrom/status/1433521867948797953?s=20

Fri 20 Dec 2024 07:17:33 PM EST

nice kit designed around 16x25x1 filters ... 5 fans tall, 2 fans along top:

filter box builder: https://www.filterboxbuilder.com/

good thread on pc fan air filters here -- suggests that the 'PST' option for pc fans allows them to be daisy-chained ...

great 'mom' post on building a pc fan air filter here

do personal air cleaners work? evidence suggests that they don't really, unless held right up to your face (maybe) https://itsairborne.com/do-personal-air-cleaners-work-f3356c85ef12

nukit night market https://cybernightmarket.com/

easy to build modular pc fan system here

clean air kits designs here

six fan pc fan corsi box here

very nice design to follow for 6 fan p14 pc box here: https://itsairborne.com/pc-fan-corsi-rosenthal-guide-a611dabf7e0c

circuit for controlling pwm for higher voltage device here

Sat 21 Dec 2024 07:01:24 PM EST

dental appliances

how to wear an ortho-tain device: https://compendiumlive.com/2022/01/efficacy-of-preformed-sleep-and-habit-appliances-to-modify-symptoms-of-sleep-disordered-breathing-and-oral-habits-in-children-with-focus-on-resolution-of-mouth-breathing

sleep posture https://www.youtube.com/watch?v=WeJrU-VJGfg

Ham radio

TD-H3 review here

Stamen toner maps

link to documentation here

DIY Boots

Sat 11 Jan 2025 08:26:15 PM EST

Trails in Waltham

Beaver Brook and Surrounding here

DIY Phone

electronoobs keyboard here

Ringo phone kit here

Tiny Home on Wheels

16" on center

Camper build series

FRP

https://boreascampers.com/blog/fiberglass-vs-aluminum/

FRP

XPS

extruded polystyrene https://topolo-rv.com/xps-sandwich-panels-for-rv/

34 mm of foam

https://topolo-panel.com/product/30mm-interwoven-pattern-xps-foam-sandwich-panels-for-rv-interior-walls/

https://steemit.com/tinyhouse/@canadianrenegade/tiny-house-episode-2-framing

Structural insulated panels (SIP)

https://rockymountaintinyhouses.com/sips-vs-stick-framing-for-tiny-houses/

EPS foam is stable once cured, no off-gassing

FP Ultra Lite @ Home Depot

straightforward, plywood-only design [here]()

Woodworking for mere mortals https://www.youtube.com/watch?v=EwJI06iyI4I

This is the key video to work from -- Living Our American Dream, Square Drop Camper Build Part 2:

25% long covid in kids https://x.com/danaludwig/status/1884919262135148678

https://www.nature.com/articles/s41598-022-13495-5

low-budget off-road camper https://www.youtube.com/watch?v=NBltrAEoGHM

another nice plywood setup https://www.youtube.com/watch?v=FS_uWkfUpaA -- part of a great series

yet another good plywood setup -- paneling caulk to supplement the glue https://www.youtube.com/watch?v=4lD_obdALDg

Building a wooden micro camper https://www.youtube.com/watch?v=HH2NAY9Up8c

rubberized coating for the bottom of the trailer

uses premium 1/4" plywood

maybe simplest just to do stick frame with 2x2's as per great video series here

Tue 04 Feb 2025 11:07:44 AM EST

Another nice 2x2 frame example: https://www.youtube.com/watch?v=zfsXUi-o3Bg -- with equations!

Sat 29 Mar 2025 08:51:08 AM EDT

Dewalt off-grid charger setup

Sat 05 Apr 2025 09:22:25 AM EDT

submersible depth sensor wiki here

Sun 06 Apr 2025 09:03:13 AM EDT

Description of the measurement board for the depth sensor here

Mon 14 Apr 2025 05:21:36 PM EDT

Diagonal braces

Sat 10 May 2025 10:57:19 AM EDT

Looks like easiest way to get serial connection via iPhone is via a serial to bluetooth adapter

Thu 05 Jun 2025 08:30:51 AM EDT

The schooner i'd booked with in gloucester is here: https://www.maritimegloucester.org/schooner-ardelle

Mon 30 Jun 2025 07:13:59 PM EDT

Spent a few hours working on the 11ty setup. No great success, but learned a little more.

Definite interest from folks in an outdoor-oriented afterschool program.

format of uart in cpy is tx, rx (cf https://learn.adafruit.com/circuitpython-essentials/circuitpython-uart-serial

i successfully used 06 for tx and 08 for rx

Lots of good footprints here: https://gitlab.com/edgecollective/neighborhood-mesh/-/tree/main/luccioloa_wide/lucc.pretty?ref_type=heads

Keyboard is here

Dimensions are 88x54 mm

side buttons are PTS645V

todo: get dimensions right, assign pins, place holes, route

Mon 30 Jun 2025 10:46:23 PM EDT

successful therapy for Covid long-haulers https://x.com/AlbaDocherty/status/1939787396666585596

Tue 01 Jul 2025 10:34:12 AM EDT

Grove connector viz https://cdn-learn.adafruit.com/assets/assets/000/078/696/medium640/sensors_grove.jpg?1564349650

Raspberry Pi headless quick start https://learn.adafruit.com/raspberry-pi-zero-creation/install-os-on-to-sd-card

rpi connect troubleshooting https://www.raspberrypi.com/documentation/services/connect.html#enable-remote-shell-at-all-times

raspberry pi connect https://connect.raspberrypi.com/devices

connection available in max 5 minutes

Wed 02 Jul 2025 12:46:21 PM EDT

Datasheet for switch https://cdn-shop.adafruit.com/product-files/805/C223-002_datasheet.pdf

Fri 04 Jul 2025 03:21:57 PM EDT

Sat 05 Jul 2025 08:55:55 PM EDT

Fri 11 Jul 2025 04:46:35 PM EDT

Adafruit instructions for updating bootloader here

using the spi bus on battery power https://learn.adafruit.com/introducing-the-adafruit-nrf52840-feather/caution-using-spi-on-battery-power

creating an mpy file here

Sat 12 Jul 2025 02:59:34 PM EDT

Current approach to radio library works alright

Tue 15 Jul 2025 08:42:57 AM EDT

Making a 12V solar charger with LM317 video here

Lindsay video here

design here

Auto cutoff here

Cutoff circuit diagram here

ACS712 here

LM317 datasheet here

charging circuit with lm317

lm317 battery charging tutorial

Adjustible DC-DC booster circuit here

This video uses lm317 for solar charging, claims better than standard equipment https://www.youtube.com/watch?v=lOxJru8VOuU

And associated circuit diagram here

auto cutoff, a little neater here

best of both worlds here

suggesting here that lm317 already has inherent current limiting characteristic -- discussion

app note on lm317 here

circuit digest article here

Focus on this one:

Wed 16 Jul 2025 02:24:08 PM EDT

the proper circuit for the charger is here https://www.youtube.com/watch?v=xvpqFcUm-lE as per convo with Mike Beach

Wed 16 Jul 2025 02:44:50 PM EDT

The 'nibbler' is for sale here

App note for LM317 battery charger here

Wed 16 Jul 2025 02:49:33 PM EDT

Ideas for STEM sailing

GPS location live Accelerometer - capsize / tilt anemometer water depth mesh radio comm

solar charging basics of batteries and voltage and current what can be powered how long to charge schwag -- voltmeter, charger

Sun 20 Jul 2025 10:10:30 PM EDT

Thu 31 Jul 2025 11:03:41 AM EDT

Neat DIY radio case https://www.amazon.com/STEM-Science-Educational-Radio-Building/dp/B0DB5R4N2C

DIY walkie talkie here

ideas for WFS

leather tool belt for skipping stones here

Some solid ideas to sketch out

bike trailer / kayak trailers

solar charging circuit prototyping and assessment

conductivity

uv254

meshbot radios

historical fiction with Judy

mobile workshops -- tarp + materials -- a lot can be done just via the car, or via bike trailer

test out a bike trailer mobile workshop in a park

Mon 04 Aug 2025 10:01:32 PM EDT

Thu 07 Aug 2025 10:40:42 AM EDT

Great video on latching circuit here

Reference at start of this video to making a battery charging circuit here

Homemade liPo battery charger circuit here

Teaching writing with precision here

Using co2 monitors to monitor indoor air quality / occupancy here

Far-UVC in an elderly care setting here

Mon 11 Aug 2025 09:04:57 AM EDT

Homeschooling resources:

draft homeschool education plans

Tue 12 Aug 2025 08:40:43 PM EDT

Latch webpage here

Datasheet for IRF4905 P-Channel Mosfet here

Great scott latching circuit described here

Update: used the latch circuit from electronoobs above, but replaced R3 with 100K.

Latching circuit with micro, here

Wed 13 Aug 2025 03:50:14 PM EDT

Nice!Nano pinout here

erase methods here

NOTE! When P0.13 is set low, it cuts off power to the 3.3V power pin on the board!!!!

011 SCL 104 SDA

Useful post on setting alarms in circuitpython here

Wed 13 Aug 2025 08:27:18 PM EDT

'every_few_seconds_control.py is the latest working code'

it seems that things are most stable when there is no pullup on SQW, and there is a pull down (100K) on P0_09 (the 'off' pin for the latch)

Thu 14 Aug 2025 02:24:51 PM EDT

Great example of a forest school website, Mulberry Montessori

amazing architecture presentations here

types of wood here

Sat 16 Aug 2025 05:13:06 PM EDT

voltmeter salinity circuit meshbot variation on meshtastic node

Sat 16 Aug 2025 06:18:07 PM EDT

used set_rtc_alarm.py to set the rtc alarm used latch_on_alarm to test.

Sat 16 Aug 2025 06:55:21 PM EDT

latch_on_alarm.py works with the circuit documented here:

note on similar circuit -- note that they suggest disabling the pullup on the rtc here

Sat 16 Aug 2025 10:57:37 PM EDT

This is the key reference -- https://forum.arduino.cc/t/switching-power-with-a-ds3231-rtc-module/687050

set_rtc_alarm_itsy.py and interrupt_itsy.py in v2 are working

using a 555 as a reset watchdog https://www.elektormagazine.com/news/small-circuits-can-do-the-job-an-ne555-watchdog-timer-part-6

https://www.youtube.com/watch?v=wcRuVxXlEKw

Mon 18 Aug 2025 08:33:06 PM Etra

traco dc dc power 5V here

cui here

Mon 18 Aug 2025 09:44:08 PM EDT

i2c library for circuitpython here

Thu 21 Aug 2025 09:18:57 PM EDT

Testing the wakup code + eeprom in eeprom_wakeup.py, /sweet-p/ver_0.4a/firmware/eeprom

Thu 21 Aug 2025 09:44:00 PM EDT

Park meetups google doc here

Useful essay on park meetups here

Thu 21 Aug 2025 10:03:31 PM EDT

No one is explaining the risk of long covid here

Link to article: https://www.deseret.com/lifestyle/2025/08/18/long-covid-symptoms-children-families-impact-congress/

Nitric oxide thread here