Thank you @jofemodo!
What a big dilemma: 0,5 pin pitch, it sounds a ROTRING line, but with a soldering iron in my hand that could transform –easily– in a Tapies tin picture 
A past experience with an old synth, trying to recover some PCB bad tracks, I had to take to service repair to get it out of the induced coma that I gave it.
I´d like doing it but I don´t dare. What about rethinking if you could solder it?
Please, tell me.
.5 is no problem 
I just built a midiphy - LoopA Enhanced Caseless Essential Kit - MIDIbox shop, DIY MIDI sequencer & studio electronics, PCBs & parts: K-LPA-00 which was full of .5 piched components! Just use enough flux and tiny amounts of solder.
I built this monstrosity with an single MCP23017 for my latetst Zynthian…
Hi everybody!
New advance… or not…
I just have desoldered all resistors (3 in each one) of encoders and, can you imagine the difference?
Yes.
NOTHING changed.
Now are performing exactly the same than before.
Not qualified to comment seriously, but does not sound to incorrect wiring?
Of course, as @Keeze101 pointed out, the problem can be encoders themselves.
Any idea or suggestion?
“.5 is no problem”
This encourages a lot! You made me doubt, but should be more safe for me than @jofemodo could solder it, if possible.
By the way @Keeze101, your electronic competences are light-years far from mine. As most of you, of course!
Would it be possible integrate this pcb instead of soldering?
I think so, you can even add 4 seperate and programmable buttons Very handy for instant jumping to different screens.
Adafruit hase one too: Adafruit MCP23017 I2C GPIO Expander Breakout [STEMMA QT / Qwiic] : ID 5346 : $5.95 : Adafruit Industries, Unique & fun DIY electronics and kits Perhaps you can source it in Spain via one of the distributors…
Soldering on anything under 0.1" ( The veroboard standard) is IMHO pretty hard. You need a fine clean tip and the modern solders are not particularly good, so get some good old fashioned leaded solder if you want to try it. These devices are really designed for flow soldering where they work very well.
You think so, but please, can you give some details of how to integrate the resembled pcb or your adafruit suggestion with midi Zynaptik 3?
Connectors to use, recommended pins, etc.
At the moment I have not been able to make it work encoders on raspi400, based on a few recommended wiring that supposedly should have to work, but until now, some give clear red errors -not working at all-, probably outdated or not suitable for pi400; and some work in erratic manner.
In this case, as I understand, 0.5 pitch is five times bigger than 0.1, so, would you recommend me go on and soldering directly over Zynaptik 3?
Connecting one of those boards to the synaptic module should be pretty straight forward. You connect 6 wires from the zynaptik board to one of those modules: 5V, gnd SDA/SCL and 2 interupt lines. Perhaps @jofemodo can tell us if we can use the Zynaptic1 connector for this?
File:Zynaptik 40pin header.png - ZynthianWiki
No! 0.1" is approx. 2.5mm which is 5 times larger than 0.5mm.
Oh, well! I did not take into account the inches symbol. Thought of speaking in mm all the time.
Now I see my encoders lost in time and space… 
Lots of good gel flux, set your iron temp at ~340deg Celsius, leaded solder wire and trust me it can be done in under 30 seconds. You may need a solder wick at the end because sometimes it bridges the last two pins.
Pro tip: have your tip very clean. Use one of those metal wire sponge thingy, it does wonders.
I have a hakko bevel tip on a Chinese yihua somethingsomething. That works well since it can hold up quite a bit of solder such that it is enough for one pass, almost.
Try to tack corners first, so you don’t have to hold it.
For example: How to drag solder SMD components #2 - YouTube
Thanks @xanderz!
The video submitted was my perdition video. The same I saw before sending my synth to service.
But, probably I underevaluate the importance of a good flux as you point out.
I will think it over…
Going on about encoders
Does anybody knows if these 2 kind of encoders, found on internet, should do the job on Zynthian?
The first one, relies on I2C connection. Apparently should be easy to implement. However not sure if it works on Zynthian.
The second one, it seems too good to be true: 8 encoders through I2C. Any idea about?
We did go a little way down this route…
The second device could certainly do useful stuff.
The real debate would be what external connector to use to connect it to the zynth…
Hi @wyleu !
If I understood correctly, none of both will work so easy as plug&play? Isn´t it?
After reading the recommended post it seems you had to struggle to make them work.
I struggle to make everything work!!
Luckily other people are rather more able.
The element is what does one do with them within the zynthian universe. There has been a little progress in making the status indicators diffrent colours which would mean that a zynth panel equipped with these could , if development headed that way, indicate system status this way.
Quite how it might be incorporated into the Zynthian interface and what function it would perform, and indeed how t might be configured are all up for grabs.
That’s not to say it wont be done because I have, for the good of the community and with no concern to personnal danger passed on one at least of these device to @riban who, whilst occasionally doing a bit of DIY, and 3D printing occasionally fits in a little investigation into this sort of thing… He’s certainly done it all before, so it’s a matter of priority.
Feel free to put together a feature request that describes what you might like to do with such a device. IT’s a great way of pinning down requirements when aroused by the wonderful new electronic toy effect we all fall foul of once we teeter on the edge of grumpy old man status to which we all inevitably decay . . .
Yes, Nurse, the stronger solution today…
I´d like to know how to struggle!
Well done, @nucklear!
Now I am running short of time, but at my first opportunity I will post my (at last!) working Zynthian with photos and video.
Stay tuned!
