Very brave to show your mistakes. Always worth remembering you learn far more from mistakes than just doing things the easy way. Glad you're not giving up and wish you luck for your next attempt
Hi, the Tester seems to work, because you hear the beeps when starting a test. It seems that there is an issue with the display only (maybe defect / contrast correct adjusted) or a bad contact from of one of the MPU contacts going to the display. You can contact me for support, pretty sure it is a minor problem.
I didn't think it was possible for someone to have more ongoing projects than I do, but here you are :P. You've still got further with your RCT build than I have, I cheated and bought one with a pre-programmed ATMega pre-installed but haven't finished soldering some of the components onto it yet.
My first SMD soldering experiences were tough, too, so don't let this failure discourage you. Drag soldering requires *lots* of flux (I use tacky flux for it). You will eventually get the hang of it. I've not built a Retro Chip Tester Pro, but you do seem *so* close. It looks like the display didn't initialize. I have my fingers crossed that @8BitMuseum can point you in the right direction!
Everything is easy when you're using the right tools, materials and techniques. When you're missing pieces of the puzzle then things get harder to solve. Soldering is one of those tasks that if you botch any aspect of it you put yourself at a severe disadvantage. You need the right solder, the right flux, the right iron, proper surface prep, etc. Just tinning the leads before trying to solder the part may have made a big difference. Today everything is lead free. That stuff is garbage. Why it's a thing is a whole other issue. But we individuals should no be punished for it.
The thing with soldering is: You can always get better at it. And people who don't think/remember/keep this in mind when they comment, really need to be reminded of it. Everything else after this line, is just me trying to help everyone who reads this comment get better at soldering. First: Clean the PCB with alcohol to get any manufacturing stuff off the board. It might look clean, but if you always clean the board, then it will always be clean. I say this, because the first shot of the board at 2:00 is a combo of tip choice, and some very strange solder/flux? Maybe the temp selection was wrong as well, I dunno. That was some strange soldering physics. It was not wetting the pins/pads like it needed flux, but you can see it there? But if the tip was far too hot, the flux would be liquifying... Anyway. That was strange, all around. It reminded me when I had a board that was, for whatever reason, coated in a thin layer of some kind of oil that would instantly oxidize the solder. 2:40 - Okay, the hot air should be the only thing touching the PCB. I can actually see the chip scooting across the PCB from the force of the air as well, so that is why there is an air adjustment. And you also want to have it more orthogonal/perpendicular to the board. I use it like a big invisible paintbrush, and wash it over the legs/package. It helps if you 'preheat' the board from the bottom, but it is not required. I also like to use tweezers to push down on the chip, more like rest them on top of it, but it also helps squish the pins into the paste and pad. Hope this helps!
I used an old arduino mega to build mine. Fashed the 2560 using an arduino uno as ISP, then transplanted the chip to the RCT. Anyway, if it ends up being the chip (which it kinda seems ok-ish) feel free to reach out and I can swap it for you.
Flux, flux, and more flux. Rosin core flux! Without flux you'll have a heck of a time soldering that big chip with the tiny legs. Also, get a better soldering tip and or solder wire.
Dude dont feel bad the only SMD shiz ive done i made little templates for, which I got the idea from one kit I purchased that had these templates that you just laid over the ship and board and made it impossible to get solder anywhere else lmao.
I really should have done more practice with bigger chips first. Up to this point I had only done small stuff and I thought I had it figured out. But I'm willing to admit when I didn't get it right!
It is better to have tried and failed than to have never tried at all. Success is falling down seven times and getting up eight. If it was easy then everyone would be doing it. I don't know much about it but I have a feeling that multiple failures lead to you not being able to accomplish your task. You will have to overcome each of them individually.
Very brave to show your mistakes. Always worth remembering you learn far more from mistakes than just doing things the easy way.
Glad you're not giving up and wish you luck for your next attempt
Thanks!
Hi, the Tester seems to work, because you hear the beeps when starting a test. It seems that there is an issue with the display only (maybe defect / contrast correct adjusted) or a bad contact from of one of the MPU contacts going to the display. You can contact me for support, pretty sure it is a minor problem.
Thanks Stephan! I'll shoot you an e-mail later tonight. I think it is probably something like that.
I didn't think it was possible for someone to have more ongoing projects than I do, but here you are :P.
You've still got further with your RCT build than I have, I cheated and bought one with a pre-programmed ATMega pre-installed but haven't finished soldering some of the components onto it yet.
I think if I take on any more projects I won't be able to fit them in my office! 🤣
My first SMD soldering experiences were tough, too, so don't let this failure discourage you. Drag soldering requires *lots* of flux (I use tacky flux for it). You will eventually get the hang of it.
I've not built a Retro Chip Tester Pro, but you do seem *so* close. It looks like the display didn't initialize. I have my fingers crossed that @8BitMuseum can point you in the right direction!
Yeah, I'm still learning this new-fangled SMD stuff. 🤣 But I don't think there is even an option for a through-hole 2560...
Everything is easy when you're using the right tools, materials and techniques. When you're missing pieces of the puzzle then things get harder to solve. Soldering is one of those tasks that if you botch any aspect of it you put yourself at a severe disadvantage. You need the right solder, the right flux, the right iron, proper surface prep, etc. Just tinning the leads before trying to solder the part may have made a big difference. Today everything is lead free. That stuff is garbage. Why it's a thing is a whole other issue. But we individuals should no be punished for it.
The thing with soldering is: You can always get better at it. And people who don't think/remember/keep this in mind when they comment, really need to be reminded of it.
Everything else after this line, is just me trying to help everyone who reads this comment get better at soldering.
First: Clean the PCB with alcohol to get any manufacturing stuff off the board. It might look clean, but if you always clean the board, then it will always be clean. I say this, because the first shot of the board at 2:00 is a combo of tip choice, and some very strange solder/flux? Maybe the temp selection was wrong as well, I dunno. That was some strange soldering physics. It was not wetting the pins/pads like it needed flux, but you can see it there? But if the tip was far too hot, the flux would be liquifying... Anyway. That was strange, all around. It reminded me when I had a board that was, for whatever reason, coated in a thin layer of some kind of oil that would instantly oxidize the solder.
2:40 - Okay, the hot air should be the only thing touching the PCB. I can actually see the chip scooting across the PCB from the force of the air as well, so that is why there is an air adjustment. And you also want to have it more orthogonal/perpendicular to the board. I use it like a big invisible paintbrush, and wash it over the legs/package. It helps if you 'preheat' the board from the bottom, but it is not required. I also like to use tweezers to push down on the chip, more like rest them on top of it, but it also helps squish the pins into the paste and pad.
Hope this helps!
I'm always looking for ways to improve and advice. This has been a great help, thank you!
I used an old arduino mega to build mine. Fashed the 2560 using an arduino uno as ISP, then transplanted the chip to the RCT.
Anyway, if it ends up being the chip (which it kinda seems ok-ish) feel free to reach out and I can swap it for you.
I think the chip is ok. I can write to it and verify it with avrdude. Probably something else.
Flux, flux, and more flux. Rosin core flux! Without flux you'll have a heck of a time soldering that big chip with the tiny legs. Also, get a better soldering tip and or solder wire.
Yeah that tip seemed less than ideal to me. But I'm not sure it was the major issue. If everything else was right I feel it could have worked.
Yeah. I thought I had already overdone the flux but no, that is never really the case, is it?
You should see some of my soldering...
Dude dont feel bad the only SMD shiz ive done i made little templates for, which I got the idea from one kit I purchased that had these templates that you just laid over the ship and board and made it impossible to get solder anywhere else lmao.
I really should have done more practice with bigger chips first. Up to this point I had only done small stuff and I thought I had it figured out. But I'm willing to admit when I didn't get it right!
It is better to have tried and failed than to have never tried at all. Success is falling down seven times and getting up eight. If it was easy then everyone would be doing it. I don't know much about it but I have a feeling that multiple failures lead to you not being able to accomplish your task. You will have to overcome each of them individually.