HeaterMeter Noob - Is it hard to build?


 

Charlie Nguyen

TVWBB Member
Let me get them cleaned up better and retake pictures.

Post cleaning... cleaning could be better but... i need smaller tools. What do yall think?

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GinoRP

New member
Was it just the LCD screen being soldered in reverse?

No. I used too much solder and repaired many shorts. I'm certain there is more. I also didn't realize the difference between the 4 bs170 and the mcp1700. I had to remove and try and reuse the parts and ended up pulling out legs on a couple. I ordered replacements. I was fairly confident right up until the LCD f-up today. I was so proud of the work I did until I went back to the instructions for the joystick and noticed the errors of my ways on the LCD. I probably used way too much heat and torque prying the screen off. I burned my finger in the process.

I was able to do all of this 25 years ago by the way. It seems that just in the last year my eyesight and steady hands are beginning to fail me.

I can, however, still program the hell out of a computer (as this is my trade.)

I'm willing to give the hardware one more chance from the beginning using all new parts; unless, of course, someone out there is willing to do it for me. There's even a bag of probably still good parts and boards in it for them. :)
 

Bryan Mayland

TVWBB Hall of Fame
Wow looks like you did a pretty good job of removing that LCD, pin 5 looks a little sketchy though. You're the third or fourth person (at least) who has put the LCD on backward. I've added a giant bold warning to the LCD step of the build instructions which may help reduce the number of people who do this moving forward.
 
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Charlie Nguyen

TVWBB Member
Wow looks like you did a pretty good job of removing that LCD, pin 5 looks a little sketchy though. You're the third or fourth person (at least) who has put the LCD on backward. I've added a giant bold warning to the LCD step of the build instructions which may help reduce the number of people who do this moving forward.

Bryan, it's the pin that has me most concerned for sure. It looks like it's detached from the board just a mm from the hole, if not right up to it. Is there a way to check if it's good?
 

RalphTrimble

TVWBB Diamond Member
Follow the trace to the next junction or via and check for continuity, if present your all good, if not either solder bridge over the break if possible or add a jumper wire to replace the broken trace
 

Bryan Mayland

TVWBB Hall of Fame
Yup exactly what Ralph said, you can just follow that trace to the via, which looks to be the second one in. Go directly left from J7 to the first via, then upper left of that is where it goes. If you don't have continuity you can just solder a wire to there too. Pin 5 is /W which means it just needs to be connected to ground (conveniently available at the right pads of R6 or C1).
 

John Bostwick

TVWBB Wizard
I had to remove two lcds this weekend from boards that I no longer used, or were just for testing. The first one came off easy, as the was no solder between the board and lcd. But, the other lcd, was a pain and after removing each pin, and it still wouldn't come off, I finally just pulled it off. Lost connection to pad #3,even though, it was still there, the trace came off. The other pads were fine on the solder side of the board.

Before soldering the lcd on the board, Charlie, make sure each pad has a good connection to another area of the lcd.
 

Charlie Nguyen

TVWBB Member
Update:

Using jumper wires, I have my LCD mounted in the correct orientation and all the connections are good, (checked continuity). thought i finished my board... and while i was comparing my board to the complete one, I noticed i had skipped the thermocouple amplifer completely.... so far i have a pretty bad rep with following directions... and now i'm just confused on what goes where. I have 6 bags of parts: 0805 10kohms, 0805 1koms, 0805 0.01uF 16volts, 0805 1000pF 16volts, and .1uF 25volts X7R 20%.

Also, i have left over a 10K OHM 1 1% vishay thermistor. What is this part for?

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Steve_M

TVWBB Guru
Update:

Using jumper wires, I have my LCD mounted in the correct orientation and all the connections are good, (checked continuity). thought i finished my board... and while i was comparing my board to the complete one, I noticed i had skipped the thermocouple amplifer completely.... so far i have a pretty bad rep with following directions... and now i'm just confused on what goes where.
I have 6 bags of parts

0805 10kohms = These are the two 10K SMD resistors for the thermocouple circuit
0805 1koms, = This is the 1K SMD resistor for the thermocouple circuit
0805 0.01uF = This is the 10n (0.01uF = 10nF) SMD capacitor for the thermocouple circuit
0805 1000pF = These are the two 1n (1000pF = 1nF) SMD capacitor for the thermocouple circuit
.1uF = This is the 0.1u SMD capacitor for the thermocouple circuit

11Ek0q3.jpg


The 10K OHM 1 1% vishay thermistor is optional for reading ambient temp, but to be honest, it doesn't provide any real value. I see that the v4.2.4 assembly page doesn't include instructions on how to install it.
 
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John Bostwick

TVWBB Wizard
The usb cable only supplies 5v to the pi and not anything to the heatermeter. Once the heatermeter is pligged in, you never use the usb cable with a 12v adapter at the same time as you will ruin the pi
 

Charlie Nguyen

TVWBB Member
The usb cable only supplies 5v to the pi and not anything to the heatermeter. Once the heatermeter is pligged in, you never use the usb cable with a 12v adapter at the same time as you will ruin the pi

The directions said to try the USB first, and I've powered it both ways, but the LCD is still blank.
 

Bryan Mayland

TVWBB Hall of Fame
I'd check the WebUI first to see if the HeaterMeter is up and running and it is just the display not working, or if nothing is working at all. If it is just the display you can trace it out and see what's not connecting, but if the HeaterMeter isn't up then the display won't work until that's fixed first.

You can also start checking things with the multimeter, starting around the ATmega:
 

Charlie Nguyen

TVWBB Member
Using my multimeter, following the schematic above, all my yellow, reds, and whites check out. I'm getting 0v, 5v, 12v dead on the money. But all the orange, green and purple ones vary from each other and most of the readings are .04 - .10V . The bottom, left pin of the ATmega, i'm getting a zero reading.

Am i checking correctly?

I'd check the WebUI first to see if the HeaterMeter is up and running and it is just the display not working, or if nothing is working at all. If it is just the display you can trace it out and see what's not connecting, but if the HeaterMeter isn't up then the display won't work until that's fixed first.

You can also start checking things with the multimeter, starting around the ATmega:
 

Peter F

TVWBB Fan
Check R20 (10k). This resistor pulls the reset pin (pin 1, the bottom left pin) on the Atmega up to 3.3V. It could also be that pin 6 on the RPI connector (JP1) is shorted to GND.
 

 

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