Shared Projects

Optocoupler to control a 120VAC 15A outlet from a smoke detector. Uses a standard hardwire smoke alarm which takes advantage of its 9VDC output “sensor line” sending high when there’s a fire. The board routes the 9V to an optocoupler. The isolated side consists of 2 non-latching relay configured as a latching circuit. If the board would to burn or lose power, the relay controlling the outlet is normally open.

The outlet is live during normal operation (when there is no fire). When triggered, the circuit will latches the relay to cut power to the outlet. The latching circuit is needed to ensure that any change in the smoke alarm trigger will not impact the state of the outlet (such as the smoke detector burning while still a fire is going on). If the board would burn as well, the relay would naturally stays opened.

The board has an additional output with pull down resistor to allow a generic microtrontroller to also pick up the fire alarm trigger and do some second level action (such as sending an email, or controlling something in a less critical fashion; home assistant status for example)

Relay 1: RT314615 Relay 2: RT214615 (also work if using RT314615) Optocouplers: MOC3023S and VOM617A most surface mounts are 1206; R1 is .25W One capacitor (220uF 25V) is in a surface mount can: EEE-1EA221P. This C1 capacitor is to allow a delay of about 200ms to avoid a false alarm.

https://github.com/serisman/stm32-mini-pill

https://hackaday.io/project/173350-stm32-mini-pill

https://www.eevblog.com/forum/blog/eevblog-1144-padauk-programmer-reverse-engineering/msg3092503/#msg3092503

Version 3. Motherboard for ESP-01 module breaking out to SparkFun’s QWIIC circuits ecosystem. Power options include USB or USB/LiPo battery and through Project STRUIX Beefy3+ FDTI breakout. Updates include an improved micro USB socket and larger diameter PTH pin headers for the ESP-01

GPS disciplined VCXO or VCTCXO with BPSK timing signal output and micro webserver for status.

https://free-pdk.github.io

https://www.eevblog.com/forum/blog/eevblog-1144-padauk-programmer-reverse-engineering/msg3091725/#msg3091725

About:

For more info visit D5T5 web .

BOM (PCB):

BOM (Enclosure):

It is released under CERN Open Hardware v.1.2 License.

This is an Arduino based board designed with KiCad Ver 5.1.2

It uses Arduino ZERO boot firmware or CircuitPython boot firmware. It has network and PoE support and many other features.

Info at https://github.com/Sd4Projects/MiniNetPad

Optocoupler to control a 120VAC 15A outlet from a smoke detector. Uses a standard hardwire smoke alarm which takes advantage of its 9VDC output “sensor line” sending high when there’s a fire. The board routes the 9V to an optocoupler. The isolated side is a latching soft switch using NPN and PNP transistors.

The outlet will be live and conduct during normal operation (when there is no fire). When triggered, it will latches the relay to cut power to the outlet. The soft latching is needed to ensure that any change in the smoke alarm trigger will not impact the state of the switch (such as the fire alarm burning while still a fire is going on). The board uses the normally open ends of the relay, such that if the board would burn as well, the relay would naturally stays opened.

The board has an additional output with pull down resistor to allow a generic microtrontroller to also pick up the fire alarm trigger and do some second level action (such as sending an email, or controlling something in a less critical fashion; home assistant status for example)

Relay: RT314F12 Power Supply: RAC05-24SK Optocoupler: ILD615-1X007T Transistors: MMBT4401 and MMBT4403 most surface mounts are 1206 R4 needs to be .25W; the other resistors are ok with .125W One capacitor (220uF 25V) is in a SMD 2924 package: TCN4227M025R0100. This C1 capacitor is to allow a delay of about 200ms to avoid a false alarm.

Adapter/Fixture buffers one joystick to drive two parallel C64 consoles.

https://drive.google.com/file/d/10CEqJVoMQ8oJLm5WLo54ebYLDSdplAQY/view?usp=sharing

Adapts a USBTiny (or some other ISP programmer) for TPI by connecting MOSI and MISO together (with resistors) to make a combined DATA signal. R1 should (probably) be 0Ω and R2 1 kΩ, but those are guesses. The idea is to connect the DATA pin directly to the programmer’s input, but connect the output with some extra impedance so the chip can override it.

https://www.hackster.io/john-bradnam/using-the-new-attiny-processors-with-arduino-ide-612185

ATtiny1616, ATtiny16xx, ATtiny16x4, ATtiny1604, ATtiny1614. Breakout board that fits a standard 14 pin socket. SOIC-14, 14 pin SMD to DIP.

Cable Adapter