DIY : tsnm (Touch Sensing Note Memory) by Doboz


#61

Good to know, thanks. I really liked the chipquik, easy to use and pretty fast. :+1:


#62

IC1 upper side in the middle: could be a solder bridge between the legs.


#63

Thanks for checking! That is just a glistening spot from I guess the flux, but i’ll DEFINITELY double check it. Haha :sweat_smile:


#64

Here is another one, its the smallest of the mutli-pin chips. It definitely looks to me like there is a connection between the pads (circled in yellow) — but i believe this is not solder but actually right on the pcb (scratch?)

Any thoughts? I am not sure what to think…


#65

An Xacto knife, carefully wielded, usually cleans up pcb shorts. Be sure it’s not in the schematic, first, though!


#66

Just checked my pcb. They are supposed to be connected


#67

Oh man, i was trying to scrape them apart too. Thanks guys.
Its going to be a miracle if this work in the end. :slight_smile:


#68

It looks like the holes on the board don’t line up exactly to the ones pcb here, not sure if i got the wrong board or if I should split the difference on the position and bend the pins a bit:


#69

uuuh no…I ordered an adafruit board too…argh…thought it would be better than a cheaper one…possible that the cheaper ones fit…:see_no_evil:


#70

these should fit! they look bit bigger than the adafruit boards…


#71

That definitely looks more like the one in the beauty shot on the site:

He does mention that the blue boards should be better than the black.


#73

ahh ok. I found one on amazon that looks right.

I’m down to the socket pins now – and trying to figure that out. I guess i’ll do the Teensy and mrp121 to the PCB first, then the ones under the mrp121 to the panel last.

edit: Actually – I wonder when is the best time to test and see if it works? – I should probably plug it in before the PCB sockets are soldered to the front panel. Anything I should be looking for at that point?


#74

checking for shorts is always a good idea. especially between V+,V- and GND


#75

just about to solder C14 with this substitute part and realized it is 50v rather than 16. is this okay or should I track down a 16v?


#76

Totally fine! Higher values are no prob!! It means the cap can handle up to 50V


#77

I can’t believe i finished this and it actually works!! :sweat_smile:

Thanks so much for all the help everyone, I definitely would not have completed it without the lines group effort :slight_smile: — big virtual high fives!

@reijo your help at the end was critical, thanks for taking the time, much appreciated.

Even the cat likes it!


#78

awesome, good work!!


#79

Cool thank you! It’s disconcerting when you are about to solder something that tiny with less than 100 percent certainty its the correct part :slight_smile:


#80

Had some time today to test it out – i’ll put that in the video thread. Thanks again all, its working as expected!


#81

has anyone found a source for the MPR121 capacitive touch board in the USA? i found one, but they are charging $14 per board!