Making a button board using an old AOL CD. Just mark where the holes should be and drill.
Then add a few other holes for the resistors, wire, strain relief, and standoffs.
The back of the board showing the one cross-connection needed (+5V to the resistor on the other side.
SD Card mod in place on a kingston adapter holding a 2GB Sandisk microsd
Lime line shows LUA memory usage in 10KB units. Ranging from 470KB-890KB. Changing to collect before fork, hovering at 389KB
Accumulation of base LUA state memory over 22 hour period. Starts at ~375KB and reaching ~610KB in 17 hours.
LinkMeter HeaterMeter v3.0 test PCB
LinkMeter HeaterMeter v3.0 test PCB populated
Make your own connectors for testing. LinkMeter V3.0 test board.
To debug, simply remove all 50 components one at a time until you find the problem, or run out of components.
Populated LinkMeter HM v3.1 board (LinkMeter, no RF variant)
WRT54GL serial port pins
Remove this mounting peg to allow the HeaterMeter board to lie flat
HeaterMeter for LinkMeter V3.1 in a Linksys WRT54GL router. The yellow line is 12V from the router's barrel jack input. The two green wires on the serial port are there because I fried my ttyS1 and are not normally necessary.
LinkMeter top casing showing LCD, probe, and fan connectors. Only 3 of the 4 probes are used.
Close up of the HeaterMeter board connected inside the WRT54GL. The button board is not connected. The LCD's D0-D3 are not used and may be left disconnected.
Fully assembled LinkMeter with 4-way directional switch and two probes inserted.
New configuration page starting point
Added some style to the configuration page
V3.1 ICSP pins. The D numbers are the Digital lines used when using the "Arduino as ISP" sketch. Optiloader should connect the pin labeled 5V to D9.
Mobile homescreen concept 1
HeaterMeter Labs. The desire to not spend $300 on a Stoker BBQ Pit Control has resulted in close to $2000 in equipment and component purchases to date.
Installing bootloader via Optiloader. Connections on this side are BLUE=D12->MISO, GRAY=D13->SCK, YELLOW=D10->RESET
Installing bootloader via Optiloader. Connections on this side RED=D9->POWER (Not from 5V!), GREEN=D11->MOSI, BLACK=GND->GND
HeaterMeter for LinkMeter v3.2. Another LCD test of the latched shift register (74HC595) on the SPI bus. Repositioned components around the v3.2 LCD connector allow an LCD to temporarily press-fit (if there's no button header).
HeaterMeter for LinkMeter v3.2, testing LCD connected to 74HC595 shift register on the SPI bus.
HeaterMeter Button Board v1 front with round button cap installed
HeaterMeter Button Board v1 back side
LMEnviro Antenna. The sheet metal forms an acceptable ground plane for the 78mm monopole wire antenna.
Just for fun: a LinkMeter Remote using a BMP085 pressure sensor for temperature readings. This LMEnviro board uses the 8MHz internal oscillator and a SparkFun 3.3V boost converter.
LMEnviro installed inside a solar powered garden light (LED removed). The RFM12B transmitter and ATmega328P microcontroller use so little power that an hour in the Florida sun will power the device for days.
Measuring RFM12B Analog RSSI from a JeeNode. The variant with the TSOP chip instead of the blob has its polarity reversed. Measure voltage across the capacitor before soldering!
Closeup of HeaterMeter v3.2 board showing how to mount transistors for minimal space usage.
Big Green Egg metal fan mount left side
Big Green Egg metal fan mount right side
Boarduino running off RasberryPi's 3V3, connected to its UART (ttyAMA0) and SPI (spidev0.0)
Resistors Installed - HeaterMeter v4.0 Assembly
Ceramic Capacitors Installed - HeaterMeter v4.0 Assembly
Diodes, MOSFET, and ICs Installed - HeaterMeter v4.0 Assembly
Buzzer, Pi Header, and BC337 Installed - HeaterMeter v4.0 Assembly
Electrolytic Capacitors and Resonator Installed - HeaterMeter v4.0 Assembly
5V Regulator, Blower RCA, and Power Barrel Jack Installed - HeaterMeter v4.0 Assembly
All bottom compoents installed, top view - HeaterMeter v4.0 Assembly
Potentiometer, Switch, LED, LCD Header Installed - HeaterMeter v4.0 Assembly
HeaterMeter v4.0 Bottom. The MCP1700-33 is only needed for a standalone HeaterMeter
HeaterMeter v4.0 bottom, probe jack side
HeaterMeter v4.0 bottom, power jack side
Tight fit in the RCA jack area. The Composite output on the RaspberryPi can be removed for a better overall fit
A 0 ohm resistor installed in R7 - HeaterMeter v4.0
Install button by placing a 3mm shim below it and soldering the legs to the board. Do not insert them through the holes.
Completed HeaterMeter v4.0 with green backlight LCD and gray 3D printed case by Tom Cole and Matt Miller
1/4" hole drilled through case for cord to go through
HeaterMeter 4.0 hanging from large Big Green Egg with cord through case
Servo damper installed on Big Green Egg wih metal plate fixture
Servo mode activated. The sliding door actually makes a pretty tight seal against the side of the 55m wide mount.
Custom servo extension cable with some style. Do not steal my fingerprints and commit a crime.
A typical HeaterMeter / LinkMeter cook graph
HeaterMeter 20130727B new dedicated servo pin is Digital Pin 8, ATmega pin 14
Ceramic capacitors installed - HeaterMeter v4.1 Assembly
Diodes and Blower MOSFET - HeaterMeter v4.1 Assembly
Transistors / 3.3V regulator - HeaterMeter v4.1 Assembly
IC socket and shift register IC - HeaterMeter v4.1 Assembly
Electrolytic capacitors, 5V regulator board, Piezo (in background) - HeaterMeter v4.1 Assembly
Phone/ethernet jack, rPi header, 16MHz resonator, barrel power jack - HeaterMeter v4.1 Assembly
0 ohm resistor for LCD backlight - HeaterMeter v4.1 Assembly
Resistors Installed - HeaterMeter v4.1 Assembly
Contrast potentiometer, LCD header, 4-way button on board top - HeaterMeter v4.1 Assembly
Cut pit probe traces for thermocouple
Solder thermocouple board onto aligning pit probe jack holes
Solder +3V3, Output, Gnd jumpers to thermocouple board
Do not install pit probe resistor for thermocouple version
RotoDamper v2 with 1" conduit BGE connection
Newhaven NHD-0216K1Z-FSPG-GBW "Pure Green"
Newhaven NHD-0216K1Z-FSR-GBW "Red"
NewHaven NHD-0216K1Z-FSW-FBW-L "Black on White"
Comparison of v4.0/4.1 PWM pulse output and v4.2 voltage output. Voltage output provides more precise control across the entire range.
Newhaven NHD-0216K1Z-FSA-GBW "Amber"
Comparison of v4.0 (bottom) and v4.2 (top) HeaterMeter sizes.
HeaterMeter v4.2 in case
Stacks of HeaterMeter v4.2 boards
Small batch of HeaterMeter v4.2 PCBs takes up more space than I had considered
HeaterMeter Local Device Manager accessible from http://heatermeter.com/devices/
HeaterMeter v4.2.4 mated to a Raspberry Pi Model A+
Model A+ HeaterMeter v4.2.4 Alarm Modifications - note SP1 bent out and Q2/1k resistor missing
Model A+ HeaterMeter v4.2.4 - note 1k resistor and Q2 bent and inserted backwards on top
Newhaven NHD-0216K1Z-FL-YBW "Yellow/Green"