When Projects Go REALLY Wrong 

Atmega8 is a legacy chip, it was used in many projects years ago, then a next generation Atmega88 appeared (along with others from the family) adding more features and improving existing peripherals. Guess someone in China had a batch of then-cheap Atmega8 chips, and they did what they often do: renamed them as a "better" Atmega88. There was a point when new AVR microcontrollers were expensive and scarce, maybe this is the reason?

The Avrdude correctly reported that it probably is an m8 chip (ATMega8). The Avrdude has a pretty comprehensive list of device IDs.

4:45 the first mistake is tinning more than one pad. That way the IC can never be flush with the rest of the pads. Only one pad must be tinned, allowing for the IC to be held in place. Solder only one pin while pushing the IC into position, then check the alignment. If the alignment is correct, solder the pin diagonally opposite to secure it in place. Then go for the others.

If pins are so oxidized that they refuse solder, clean them off the board. Many of those solder connections of the fake chips still looked not connected well even after your last attempt. As for wires, do yourself a favor and get a spool of wire wrap wire. That is great for all wire connections that must be thin. They only need to be tinned before using, because they are not meant to be soldered.

Surprising how few people here recognise the root cause of the difficulty you had getting solder to bond with the IC legs, but it's very simple actually. You could see those off-colour, dull looking legs from across the room. Loads of corrosion and/or some sort of dirty build-up. Fresh tip: don't bother trying to solder onto corroded / dirty metal. Solder needs to actually contact the metal surface, and the metal surface of course needs to be at a similar temperature to the melting point of your solder at the point of contact. Careful mechanical abrasion is usually what you need! Like, a small square of medium / fine grit sandpaper held with tweezers. Or just the blade of an X-acto knife. Then scrub with a bit of IPA, dry it off, and get to work. Sometimes only the scrub is needed, with an organic solvent (IPA, acetone, MEK) if you just need to displace some tacky or oily dirt. There is the option of using an active flux. These are usually acidic (often phosphoric acid!), and typically not noticeably aggressive at room temperature. But, with the heat of the iron the acid gets angry and can eat through most corrosion. Some active fluxes are *very* active and will easily eat through Fe2O3 (red rust), and your soldering iron tip. Note, however, that you must clean active flux residue off VERY thoroughly. And I do mean VERY thoroughly. Any residue hiding, say, under an SMD component, will destroy whatever it's touching (starting with exposed contacts and copper traces) over the course of the next few months / years. It will catch you out. Not recommended for this kind of work.

You forgot the basic number 1 rule of soldering.... heat the pin AND pad at the same time while touching the solder to the pin.... when the pin is hot enough the solder wil melt and flow properly to the pin and pad and the joint will be smootth and shiny.

yeah, we all love success stories and clean soldering but personally i admire most creators who share their failures for us all to learn. Great job and fantastic final product Noel!

Oh boy. I went through 6 pairs of Darlingtons and 4 rare Schottky diodes and finally blew a loudspeaker from replacing power transistors with Chinesium ones. Then I bought UK sourced ones from a reputable supplier, a replacement voice coil from the USA and finally got an old Fender guitar amplifier singing. Like you, I wondered why would they bother to rebadge scrap at such low prices? Then I remembered how Sir Clive Sinclair started in business...repackaging scrap transistors and reselling them as 'special' ...

I'm an electronic technician who specialises in rebuilding and restoring older machines, like Neumann matrices engravers for vinyl mastering, as an example. I understand the frustration that comes with that kind of work. I spent a couple of days searching for intermittent trouble in a machine I just finished to rebuild. Since the client and I had already invested 10k in time and parts, I wasn't allowed to give up, I found the trouble, but man, do it get frustrating sometimes, lol 😅

Those first chips looked like they were made in 2010. They have had plenty of time to corrode, especially if they have not been stored properly. You can actually see the difference compared to the new ones. The old ones are grey and ugly, while the new ones are nice and shiny. The bad soldering was not your fault.

Hey Noel! So, I'm about 7 minutes in. You first mistake with respect to soldering the chip is you DID NOT heat the pins themselves. Solder sticks to hot metal, it really doesn't like to stick to cool surfaces. A bigger tip DEFINITELY would help here, your general technique is great though. You probably could use hot air here. I'll update via comments my notes to you.

If these are harvested and re-branded chips, the harvesting process may have subjected the leads to far more heat than is normal. This could cause damage to the silicon (hence the bad chip you found) and/or so heavily oxidize the solder on the leads that they become extremely difficult to solder. This is the reason I only buy from Digikey or other reputable sources.

This is a great lesson in problem-solving. It also warns us to be careful about the chips we buy. Most counterfeits that I have seen have blurry lettering and incorrect logos. Try to find images of genuine chips online and compare. Another great takeaway from this video is that there is now a new source of SID chips for the Commodore community. Hats off to whoever created it.

The important part of soldering is to heat up both pieces of metal to be joined at the same time. Applying the tip of the iron just to the pad isn't heating up the pin, therefore you won't get a good joint.

Lots of good info in the comments on the specifics here, but as a guide for other who may be hobbyist solderers(?) from someone who does a lot of nano and micro rework by hand as a job: I use tips way bigger and iron temperatures way hotter than you would assume for any given task. Plus, not all tools and materials (station, tips, solder, flux etc) are born equal. I have helped beginners who's starter soldering kits make things additionally hard for them and me! One tip when using a monocular scope/screen is that pins can look OK from the top down and a decent nudge test is the only way to check, and absolutely soak the pins in the first place.

Welcome back, Noel. I was a bit worried about you after so much time. Thanks for another great video!

6:50 oxidization on the chip legs maybe? it was sticking to the pads fine. mayeb the chips were old and had been exposed to the elements?

19:25 One trick I've heard of to make pin header "blocks" is the superglue the individual parts together.

Some chips are harder to solder than others. What stands out to me is that you only heat the pad and not the pin. For the best results, you need to heat both the pad and the IC pin with the soldering iron. If you don't touch the IC pin, it will be at a lower temperature and won't pull solder onto it. Additionally, if it's an older IC that wasn't stored properly, there may be some oxidation on the pins, so it's essential to burn that off with flux. Therefore, heating the IC pin is crucial for successful soldering.

Great to have you back. I felt your pain. My tip to check SMD solder joints: hold the board at a shallow angle and look through a magnifier. If the joint is good you’ll see a shiny ramp of solder from the pad to the pin. If you see anything else (ie a step) the joint is bad. Since discovering that I’ve not had a duff joint.

From my heart: This was the most exciting YT post in many many years. Thank you sooo much!

Fantastic video! I love how you explore the difficulties and mistakes during the Nano SwinSID build, especially dealing with soldering issues and counterfeit chips, it must not have been easy. It's really true that even simple projects can have unexpected challenges. Looking forward to more content like this. :)

27:37 that's why when i am soldering any SMD components like QFNs i gently push on them to make them flush with the board; unless legs were bent before usually it suffices for good contact. And yeah, apply that much heat during soldering to actually heat pad AND the leg to avoid dry joints.

Ugh, what a frustrating mess! Excellent persistence, and thanks for the shout out!

29:37 oxidation, one that is removed with flux and good amount of heat.

Regarding the probe tips: First thing, I always shaped the original probes to a sharp tip. Use a file, belt sander, whatever gets it done. Sharp pins work well and do not slip nor short pins to each other. Solderability is also a problem. Pre-tin procedure sometimes helps.

We all stink at soldering until one day we just don't. It's super weird.

Man, this led ya on a merry chase, no? I am no expert on SMD soldering, but I have done a bit of it in my time. If you don't have some, get some rework flux and low melt solder from a reliable vendor (I like Chemtronics, but that just me). It can make a surprising difference, especially when using hot air. Of course it didn't help that your microcontroller chips were heavily oxidized from the recovery process. That discoloration on the legs was from heat, and it really made things difficult for ya in terms of getting the solder to stick. You figured it out, though. Those chips are cheap enough that getting new stock from Mouser was a genius move, especially since the first ones you got were rebranded junk not actually suitable for your purpose. Time, patience, and perseverance encompasses all things. Your eventual success here is a prime example of that. Thanks for sharing your trials along the way so we can all learn from them! That kind of gold one doesn't find every day.

I'm not sure what's going on with your solder or solder technique, but for sure those solder beads aren't acting right on that microcontroller. The solder should be "wicking" under and even up onto the chip legs. Like if you were using a reflow station, you don't even *touch* the legs. You just tin the pads, apply hot air to the legs, and the solder wicks up and connects everything. I'd probably take that chip to some sandpaper or emery board to eliminate the possibility that it's got oxide on the underside of the legs. I'd also probably check my tin/lead ratio on the solder. If it's all tin, you just have to deal with the fact that it's not going to wick as well I guess. But definitely if I was experiencing what you were experiencing when you were trying to mount the microcontroller, I'd have stopped and solved that before moving on. Something's not right. Solder's too cold, bad lead/tin mixture, oxidized legs, not enough heat being applied to both the legs and the pads, **SOMETHING**. The way that solder was acting, you're almost guaranteed to have a cold joint.

We would say "wenns bärt, dann bärts" which means "When things go wrong, they really go wrong all day long"

Great job Noel, glad you got it finally working! And about the microcontroller: I had several problems with my Kung Fu card, I bought it a longer time ago on ebay and when it did not work anymore (sometimes it did, then no longer), I opened it up and was shocked about the soldering of the microcontroller and components. The controller pins were mostly loose, no connection to the pcb, I cleaned everything with Isopropanol and resoldered the chip, but as in your case, the solder had no intention to make any good connection. It took a lot of cleaning, flux, and good solder and a huge amount of patience to get the chip back onto the pcb, that was as in your case, the chip had no goog connection and refused to work. Luckily I finally got it working again and had no trouble since... so I can exactly imagine how frustrating it is to solder in such bad connection conditions... Greetings, Michael...

As soon as I see a hot air rework station, the phrase “easy build” takes on a whole different meaning. Like car repairs/mods that require you to take the engine out.

One of the most braindead things in Windows USB drivers is that they are port specific. It is to me completely absurd that the device gets treated differently in a different port. I mean, it is good to have that as a possibility, but not as a default! This has been the way since at least Windows XP (probably even in older versions), and you can e.g. see Windows installing new drivers whenever you plug a device to a port where it wasn't before. This is particularly problematic when the default drivers don't work out of the box... I think Microsoft doesn't really know what the "U" in USB stands for.

I'd use some solder paste instead of a wire for that chip. Has included flux and a lower melting temp (lower temp difference = easier for it to stick), much easier to work with small pads. You can also place it before you add the chip, so that it is much less likely to not make contact

It really looked like there was some kind of oxidation on the pins of that ATmicro. That would make soldering nearly impossible. I'd try some ultra-fine sandpaper on the pin's contact surfaces.

With SMD try a K tip for your soldering iron. Don't tin any pads before placing the part. Solder paste can help. Just don't give up. I started with AVR stuff and a few years later I'm now working with 400 pin BGA parts.

I always admire you for your endless patience and creativity in solving problems. I am one of those people with a, em, shorter temper is a nice way to describe it? To finally get it working. Class!

You've got quite some suggestions so maybe mine is redundant but: 1. yes, you need the biggest tip you can use for soldering. Maybe that chisel one is too big though! :) 2. Heat up the pad and the leg for 1 second, THEN apply solder. 3. Solder wire, flux, solder tip quality they all make a huge difference. I use Loctite solder wire, Kingbo flux (Amtech is just way too expensive) and I believe you have a Hakko? Those are genuine Hakko tips? Fake tips will deliver... fake results :) 4. Apply more solder on the first pad. Only one pad or the whole chip will be elevated. Once the first leg has fallen into the solder - and the whole IC has touched the PCB - then you can solder the second leg, then all the others. Good luck! :)

You should have a Linux machine (or dual boot) for this kind of thing, it's much easier than dealing with Windows drivers and idiosyncrasies.

Thank you Noel you have given me such a boost in my confidence knowing that I am not the only one who makes mistakes and stuffs things up with the solder iron. Cheers

This is an important video. A reminder that things can go wrong and you can learn and try to avoid them. I like the idea of a small sid replacement, it can just look alien alongside simpler chips but still, a great idea.

I think it is important to see also videos like this. Often I do not remember to read properly the messages. I am quite varied about the fake chips that are around and it is difficult to find a reliable source that suits for hobbyist.

Thank you for making this video. I learned a lot through it. It was great to see your process and understand how you went through figuring out each of the various different issues and overcoming the problems.

This was a fun journey, and I'm happy you shared it with us, dealing with bugs is annoying at the moment, but these are the moments we learn the most. ;D

I feel slightly better about my own soldering skills now. Not good, but if you can struggle then I understand my own struggles a lot better. That microscope is looking like a game changer...

I know everyone is a know it all with soldering, but maybe something that will help is using a KU knife tip. I very rarely use anything else and works great for through hole and SMD components. Those tiny cone tips are absolutely useless, and as long as there is flux aplenty, I find bigger tips are fine for even tiny components.

You have great patience & perseverance. I think I honestly would have given up on that long ago. Glad you made a video on it though. Shows how perseverance can get you the results you want/expected! I've just ordered a programmer (waiting for it to be delivered) as my sister car radio doesn't work and common issue is a bad firmware so I'm going to "attempt" to read the firmware to see what is currently on there and re-flash it with hopefully a working one. No idea what I'm doing... so this video was very interesting for me as once its delivered, I need to figure out what the pin configuration is!

Thank you for sharing this video, Noel. I have been in a similar situation not long ago, but ended up giving up and concluding a lack of skill. Your video showed me it is not just me. I should give this another go…

When microcontrollers or anything in similar packages do that I will use very fine grit sand paper and sand the leads a bit. Makes a MASSIVE difference for me.

hey noel , thanks for the channel its filled to bursting with tips and tricks so an amateur like me can tackle our problems

I used to watch Louis Rossmann to learn about microsoldering (and some salt - now it's all salt - so look at early videos) as I wanted to repair lots of broken things I had around me, PS4 and XBox 360 HDMI ports, USB-C port on a phone etc. So I bought the equipment that he used (only in function, not exactly the same) and started learning to solder with hot air needing very little iron work. I got very good at it. When you took the dead IC off you used hot air, do the same for putting it on, it saves a lot of time. Just put some solder onto the board, either paste or wire with the iron, then plenty of flux, heat the board, then place the IC onto the board and keep swirling the hot air around the legs, eventually the IC will magically float into place, gently tap it with tweezers and remove the heat. Job done. Regarding the fake parts, the wrong signature is real red flag - it means you don't have what is marked on the IC so that immediately shouts fake. It is also likely that the process the Chinese component sand-and-etch brigade use affects the plating on the component legs leaving a scale that needs a lot of heat and flux to remove. The connector looks like 1.27mm (0.050" - 50 thou/50 mil) I guess if you were programming in any volume, you'd make a jig to push spring loaded pins onto those pads from below.

You made super hard work of that. The bad soldering early on should have been a sign but you just powered through it. Plus the device ID...

Really interesting video. I also get worried about causing a short circuit when I need to take a measurement and the two pins are very close to each other. And let's not even talk about when the plastic melts while trying to solder a connector 😅

As someone who has been doing SMD soldering for over a decade, you pretty much nailed it that the tip was all wrong. Chisel tip, load and drag. You got the amount of flux right at least. Not sure what temp you were soldering at. Looked a bit cool, especially for that tip. Bit painful to watch stuff like this. Edit: Some medium active flux would have helped as well.

Great video! Loved watching your troubleshooting process, and learned how easy ICSP is to use!

32:18 at my previous job, we worked in product testing, for safety, so needed to be able to turn on programs running test software, and often had computers like this. Yes, the USB port mattered, we were often on the phone and email with clients demanding exact instructions on how to set everything up from the very beginning to avoid these "Different USB port" issues.

There are so many cool projects I'd like to do, but I don't. When I was young, I had energy and was sharp. I also had confidence and better fine motor control. As I get older, I find I'm losing those qualities. I end up getting really frustrated and if I'm lucky, will get the job done with a lot of blood, sweat and tears. If I'm unlucky, I'll put it aside and never come back to it.

Great video, it’s nice to see we all have failure. Whats better is that you give us the incentive to keep going even if seems like it’s obstacle after obstacle! Fair play, and thanks for the heads up!

Awesome video. I'm a bit of a novice, but I've been trying to build custom devices with the Raspberry Pi. You channel has helped so much in learning systematic troubleshooting. This one also helped in the don't give up part of building a project. Keep up with the great content.

Nice to see you back. As already commented, for a good solder joint, BOTH parts to be joined need to be heated up adequately. The solder will then melt between these two pieces and not tend to stick to the iron. If this is too much heat for the part in question then you have to make a pause in the soldering to let the body of the part cool down. This can be particularly the case if the pin being soldered is connecting to a ground plane or anything with a big thermal mass. There is actually a specification for how much heat can be used when soldering, usually 300°C max for 10s max (cumulated, not per pin) otherwise there is a risk to damage the bond wire from the pin to the die. It is not a good idea to pre tin the pads if you are going to solder with an iron afterwards. This is because the part will not be level on the board in turn because of the uneven amount of solder on each pad. But is is perfectly Ok if you are going to reflow the board with hot air because then all the pads will melt at once and the part will 'sink in' the solder blobs. As an aside, unfortunately the parts from Ebay can be hit and miss.

Your video reminded me that I have a partial set of 6581 lithographic masks somewhere in storage. Wish I could find someone with the remaining masks to make a full set, and then a foundry that could churn out a batch of original SIDs.

This counterfeit chip business is crazy. Wish someone would take an in-depth look into how much is actually made form these low-cost chip rebrandings. I faced that a long time ago when I bought power transistors for my Fender Passport sound system..

16:50 Why don't you crimp some new Dupont male pins? I would still solder the 1.27" pitch header, and solder to the pins on the other side, bent them up and down, not sideways. Shorting power should not destroy your chip, perhaps your programmer could get damaged.

Hi Noel !! This happens too much here in Brasil !! Super low quality of the leads of the chip !! Some Chinese chips must have the side down of "legs" *_gently sanded_* and ressoldered to get a good quality of assembly !! Or some drops of _*deoxit_*... Cause of our tropical weather, all stock chips tends to little oxidization !!

That was a really helpful video. Thank you for showing the good, the bad, and the ugly.

You need a mini wave tip for your iron, it makes surface mount ICs like that a 2 minute job. I don't know why nobody uses them on youtube. Its like a chisel tip but has a hollow cup on it you load up with solder and drag across the pins, perfect job every time.

When I first started soldering surface mount, I also thought "small tip = better." And like you I had SO much trouble with it. It's counter-intuitive, but yeah, a bigger tip works better. These days I use the same chisel tip I use for through hole soldering and it works quite well. Just drag solder it, and resign yourself to the fact that you WILL get bridges, but with some careful application of flux and/or wick, they can be easily cleared. To make it easier to shove stranded wire into PCB holes, it really helps if you pre-tin it. Takes a few extra minutes, but saves SO much frustration in the long term. And yeah, trying to probe small IC leads with a standard multimeter probe is a recipe for failure. A bit like trying to park a SUV in a parking space for motorcycles. I've lost count of how many things I've shorted out because my large standard multimeter probes accidentally bridged something that shouldn't be bridged. Get yourself a set of fine tipped probe leads. They're not that expensive, and are FANTASTIC for probing small things. Just be careful when using them; if you're not, you can end up accidentally jabbing yourself somewhere, which can be quite painful. Ask me how I know. :) Looking forward to the SID replacement shootout video. My C64 fortunately still has a good SID (and it's even the well regarded 6581R4AR) but you never know with these old chips, it could die tomorrow. So I'm interested in the various SID replacements that are available these days. Will you be covering the SIDkick Pico? It's a relatively new kid on the block but looks VERY promising. First of all, there are only a few surface mount components, and they are the larger 0805 variety, which are fairly easy for even a novice to solder. And it uses the Pi Pico to do the SID emulation, which is a through hole component and is extremely cheap and easy to obtain (and also A LOT easier to program ;-) ). It uses the reSID code, the same code that drives the SID emulation in the VICE emulator, which is said to be extremely close/accurate to the actual SID in terms of performance and sound quality.

Most of this seems like assembler error.... Soldering technique and not being familiar with tooling Thanks for sharing your learning process and experience for everyone to learn from!

For measuring on these fine pitch layouts, you should have a look at probe master spring loaded micro-tip test leads! They make a WORLD of difference on stuff like this!

That was quite the adventure old boy! Glad you got it fixed... Nicely done.

I have a few nano's rattling around in a drawer somewhere. Now the SwinSID Ultimate is a different story. I love that one. But getting ahold of one these days is a bit tough. My favorite has to be the FPGASID. The psudo-stereo option is fantastic. Voices 1&2 on left speaker, Voices 2&3 on the right speaker makes old games seem line new.

Yeah, it's definitely wrong tip (I also learned it hard way). You need knife-shaped one for this job. Also don't be afraid to bridge the pins while soldering them, that can always be cleaned up later with some flux and solder wick.

Congrats! Genuine distributors should the first place you look, buying chips from online marketplaces is a risk you take when you've run out of other options. Great video as usual, I love your perseverance and glad you won in the end.

Like your video. I always, always check my connections with a multimeter to check for proper contact AND shorts of supply rails and all other traces. When I do apply power , I do so with a bench power supply and limit the current to 50 mA. If anything has been overlooked the current will be very small and most components will survive that much current. Plugging the board without testing to an USB to FTDI adapter that can supply upwards of 1 amp is not smart. Stuff will release magic smoke if something is wrong. Same goes with repairs, always use current limiting and know what voltage is needed for supply and digital/analog interfaces.

I think, maybe the μCs are a bit old and the pins were oxidized. That could explain the soldering problems. What makes SMD soldering fun is a hot plate. I have been hand soldering SMD for probably 30 years, but the hot plate was really a step forward. Much better than hot air. And for cable making, crimping is much nicer than soldering. The IWISS SN-025 tool is great for Dupont connectors (although all crimp tools seem to be recommended for Dupont, the previous tool is the only I know). The SN-28B is good for many other crimp terminals.

Wow, sorry you had such a rough time. I would have gladly sent you a swinsid to avoid that hassle. Since you solder way better than me, I can't offer much advice on technique, but for SMD soldering I do like my mini preheat table. The solder seems to flow a little better. Glad to see you had time to put out a video with as busy as you are.

Sometimes when we are too focused on the end goal we miss the detail on the way.

I had a very similar experience with my first PiStorm build. So many things can go wrong!

I've had similar dry solder joints but I do find if I use an eye glass, something like x20, I can see clearly a good or bad joint. Cheap and important investment.

3rd-ish time's the charm? What a wild ride; I wish this kind of odyssey was less common, but glad you got there in the end. Great reminder that sometimes it isn't you (and sometimes it is) 🙂

thats why IC-s are kept in moisture controlled enviorment. That chip was probably siting in amazon rainforrest for a while. Even the flux could not get rid of oxide. Soldering with a axe, wont help also.

One trick I have used is to drag a pointy XACTO across the pins. Sort of like an old mechanical music box on a harp. This is quick and will show any of the pins where both sides did not heat up correctly. My other guess is whatever the seller used to re-badge these left a residue on the pins making it especially difficult to solder.

I should start to make RU-vid videos too. ALL of my electronics projects go wrong. Buying chips from Aliexpress is one of the biggest contributors to that. I totally felt your pain when I saw the soldering challenges. I spent all day Saturday doubting my soldering skills due to dodgy CH340 chips from Aliexpress. When I was a kid I used to kill many ICs trying to desolder them so I've always been wary about how long to keep the iron on pins. That's the whole reason I've been too chicken to solder a Spartan 3 FPGA onto a PCB. Drag soldering scares me - always worried a bridge will form underneath the IC somewhere where it can't be seen. The other mistake I make is trying to design a PCB, getting it manufactured, waiting 2-3 weeks for it to arrive and then discovering there's a mistake or I haven't added something. Just did that - didn't add the ISP pins to program my AtMega2560.. I'm glad to see that other people experience this pain. I keep thinking it's just me and that maybe electronics and I were not to be :-)

Wow! Interesting! Funny enough that I once ordered ATMega8 in the false form factor. Wanted to by DIP but accidentally got the type you had. But the best thing about seeing you struggle to solder those chips was that it made me think about my plan to try soldering SMD for the first time on a PCB that has only SMD components and a lot of them. (RGB adapter board for Aplle IIc PAL), I think I better ask a friend...

One tip: Watch the length on the programming wires. I try to stay below 6 inches. Never had a problem with micros but I have with Altera FPGAs.

you should be using paste and a hot plate to solder the microcontroller. as for the tiny programming connector, the best option is to make a pcb programming adapter with the proper connectors

6:57 Yeah lol. Years ago I re-designed my own swinsid board and made the design much better including getting rid of those silly small-piched holes and 43:28, yes there is room. I added the proper 2x3 AVR programming header :-) If you want my gerbers or the full source Eagle PCB files let me know.

I personally would have stuck with the small tip. It looks like you primarily heat the pad in your first go at it, heat the pin as well next time and it will go much better. Big chisel tips avoid the issue by just dumping heat everywhere lol but that’s not exactly necessary

I used to work in a production environment. I'll not say the things people already said, like heating the pin and pad evenly. But one thing I learned the hard way was when using wick you have to add new solder. It sucks out all the solder amd you can't see that it made a dry joint. Do NOT force the device check. Some devices have different program spaces, like the mega2560 and 1280. You can accidentally rewrite the fuse thay controls the SPI and brick your device.

I feel your pain Noel! Ordering lead finish PCBs and using leadfree solder is putting soldering on 'hardest' difficulty. Thanks for sharing and can't wait to see more of this type of content

ALL of the retro youtubers I follow had to deal with fake chips

What a nightmare! When you compared the two microcontrollers at 39:00 you can clearly see the difference in the pins. New vs old and crappy looking.

I ran into a similar problem recently. I was making a replacement for the keyboard controller in a Mac Plus keyboard. I initially prototyped with 40 pin Mega32 (needed a lot of I/O to match the matrix along with everything else) and same problem - the IDs didn't match. I got that batch from Amazon. They kind of worked anyway, but I got more from Digikey and they were perfect. Finished up with a surface mount version in a 40 pin DIP form factor. I saw you used hot air to remove the chips, but have you tried it for soldering them on? The Mega32s I had to use were much finer pitch that those 88s. I just laid down a thin line of solder paste across the pads, stuck the chip on, and hit it with the hot air. Once the solder melts it's attracted to the bare pads and legs and it just kind of "snaps" into place. Way easier than trying to do it with an iron.

clean solder iron tip, pads, and chip legs and wait for the solder to "suction" like water surface area in a cup.

Noel. You can test to see if a suspected chip is rebadged by rubbing the chip with a cotton swab soaked in rubbing alcohol. Fake chips the label will rub off. But you knew that already. Great video. Really enjoyed it

I smoked an ESP32 chip the same exact way by stupidly shorting one of the i2c lines to 12v power from a shunt. The slightest little slip a buzz and a spark and that’s it, all that work gone out the window.

May I suggest you get yourself a set of Probemaster probes. They are very pointy and gold plated. It makes a considerable difference. I am very happy with them. The most basic set will do.

I've never done SMD before, but in this case I'd try drag soldering the pads. All of them. Then putting the chip on and using hot air. After that works (assuming it works), i'd try soldering 1 pin at a time to fix any issues from the hot air soldering and any lack of solder initially used.

YEAH!!!!! More Noel! Been hoping and waiting. Thank you!

Lol Noel buy a decent iron (I use a JBC) and the fine tip will work perfectly. You could easily see that the solder had not wetted to the pins. Fun video :-)