Meshtastic

Does the T Beam screen have to be soldered

If so, are there any tutorials on actually doing it?

definitely needs to be soldered. The pins are highlighted in this picture (make sure to double check SCL and SDA are as shown (SCL to pin 22, SDA to pin 21).

As far as the soldering itself, I bet there are some good youtube tutorials but alas I don’t know of one in particular. If you find one that you like please provide the link and we can add it to docs/README.md in the github project (which is what generates www.meshtastic.org)

Does it require any special tools? I have a soldering iron, but it might be too big to make those tiny connections.

What search terms would a person use to find something like that? I’m not sure what those little connectors are called.

Well if you want to take electronics soldering courses, just go to YouTube and you will find lots of guides and the equipment you need.

re: regarding the pins out in the site where you bought your ttgo they show you which pins you need to use.

I marked the pins indicated with red

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Some broken old (computer) unused components boards are a good option to practice soldering, desolder a few components etc. Large iron as in 80-100w is probably a bit too much if possible 30w or less.

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As you are only soldering pins you can probably get away with a big, hot iron but you will still want to be quick about it.

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I learned to solder last week in order to do some TBEAM screens. I bought this cheap soldering kit and it was fine: https://www.amazon.com/gp/product/B07GTGGLXN/

It has everything you need except maybe some helping hands, which I also bought: https://www.amazon.com/gp/product/B081DSR68P/ You could probably get away without these but it helps to hold everything in the right position.

I bought a soldering practice kit as my first project and then soldered 4 TBEAM screens as my second, no hiccups to speak of. If I do more screens maybe I’ll make a video.

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Please do!!! That would be most helpful!

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One note. The 3v3 power is in between 2 GND’s… Things get very hot if you, say, get the GND and the 3v3 reversed… I ahem know a guy who did that and it wasn’t pretty. (me. don’t be like me!).

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They should sell the TBeam with the screen already soldered

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YES! Yes they should!

My TBeam came in an antistatic bag inside of a brown airbubble bag. Soldered screen will probably not survive the jouney from China like that. But agree a fix screen option be good.

I think the reason they don’t solder the oled is something different:

When fabbing modern PCBs surface mount parts can all be machine placed and soldered. Through hole parts usually need to be hand soldered. Which is why mfgs try to avoid those parts (especially for cheap boards). Initially TBEAMs were sold without displays and then hobbyists started adding the OLED and so TTGO started bundling it. So the screen wasn’t really designed for this application.

I’ve been informed of a board that is ‘in production’ that sounds ideal for meshtastic. This new board is more designed with this (and similar) projects in mind and therefore I assume they will come with all parts soldered. Whenever the MFG is ready to announce something I’m sure they will.

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do you have more info on this board ? :slight_smile:

Mine (Aliexpress) came in small plastic boxes, with the OLED screen in separate boxes.

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I’Ve asked Lilygo if it is possible to buy a screen soldered version of t-beam, the answer:

thanks for your feedback , we will upload the version with the Oled screen already soldered

Not sure if they understood or a bad translation

I have a lessons learned on the soldering. The four header wires are pretty large, I found it was MUCH easier if I cleaned and pre-tinned the leads before inserting them into board (particularly the tbeam side since the battery case is close to the holes). I had to scrape them down a little since the pre solder made the fit too tight.

Trick being with soldering is to remember that you need to heat up both parts and let the solder surface tension do the work of joining the parts.

That means for the T Beams, angling the soldering iron so that touches both the pin and the ‘ring’ on the PCB, let the soldering iron sit there and touch the solder to the pin (not the iron). This way when the pin can melt solder, the solder will melt and also fall onto the ‘ring’ which is also hot enough to melt the solder.

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