ZX Nucleon 512KB - Build Part 1 - SMD

[@HappyLittleDiodes]

Thanks everyone for the SMD soldering tips! I will put these to use next time they are needed!

[@repetto74]

You absolutely need to use flux for SMD soldering. It is the key for nice solder joints and no bridges.

[@jaycee1980]

Best way to do those big D2PAKs is start by tinning the pad as you did, as flat as possible.. but then BLAST IT with hot air. Then sit the chip down with flux. As you've discovered that big pad will absolutely just suck the heat away from your soldering iron. Another way I've done it is to sit it first, solder the main pins, and then blast it with hot air before feeding the solder in at the top. Normally enough flows under the chip to make a good joint

[@preferredimage]

A tip I picked up from off all people, a plumber... with large pad SMD stuff (much like a copper pipe joint) you add loads of flux between the parts. then bang on as much heat as you can manage, then just when its all bubbling nicely, dab in the solder and it instantly melts and due to capillary action, flows between the parts and makes a solid (water tight) seal. Also, the flux acts as a glue to hold the part in place so you aren't pinging things around the workshop.

[@hbox21]

good work looking forward to the bootup

[@cv643d]

That part at 5 min, add flux to the pad, then place component on pad, then pre tin the tip (wet the tip), then hold the wet tip on the edge while holding onto the component with a pincette, once the pad and component heats up the tin will flow and form a bond between the component + PCB. Once a bond is set you can add more tin to it.

[@HappyLittleDiodes]

Great tips thank you I will do this next time

[@markretro3612]

i am new to SMD but what i have learned is flux, flux & flux again

[@HappyLittleDiodes]

Thanks for the tip!

[@meh3247]

I've worked quite a lot in surface mount, and we always printed solder paste (with flux in it) onto boards, placed components and then baked the boards in specialist ovens. Of course, this was for bulk orders so printing the paste isn't really applicable for you, but syringing blobs of solder paste in the right places and heat gunning might be - I guess it depends on how much surface mount work you do... Just a thought.

[@johnrose5312]

Great video - the explaining the circuit as you build it is great learning for me

[@HappyLittleDiodes]

I'm glad you said that because I thought it was a good way to do a build! I've been learning a lot too

[@Retroguyuk75]

Cool project. Love that purple board colour.. Still love my black Superfo 128k keyboard.

[@spacepygmy4443]

Nice , looking forward next vid ,🎖

[@HappyLittleDiodes]

Coming soon!

[@TRONMAGNUM2099]

Wow, Can't wait to see what a 512K ZX spectrum can do. Maybe even play Doom.

[@HappyLittleDiodes]

Now that would be a cool challenge

[@GodmanchesterGoblin]

A couple of points if I may... please don't refer to chips by the first two characters of their part numbers - it is incredibly ambiguous. AY chip... LM chip... Both General Instrument and National Semiconductor made huge numbers of devices with those prefixes, and even in the context of the Spectrum there are other parts that can begin with LM. Power inductors are not orientation specific, so no problems there. However, the current rating in the inductor datasheet is not the same as the output current of a circuit using that component. It's the peak current that the inductor can handle without saturating (magnetically). The output current of the circuit may be less than a third of this rating depending on the specifics of the design and circuit conditions. Thanks.

[@zxrenew5642]

Gel flux is your friend. :)

[@josefjelinek]

I do not understand one thing. You seemed to struggle to solder the voltage stabilizer on that big pad - understandable. So you decided to use hot air to remove it and start over. ... You used hot air to remove it... and not to attach it in the first place... at the time when no other chips were on the board to be affected... Just trying to understand why. Other than the soldering, which seem to need a bit more deliberate practice (and a rework station if I can advise), really good info sprinkled in! Thanks.

[@HappyLittleDiodes]

Yes I've learned a lot from this and will do better next time 😉

[@moonandwanderer]

nice!

[@Xalior]

I want a purple one now... -Dx

[@HappyLittleDiodes]

I think they are discontinued! Looking at their last ebay listings for assembled boards. "The last piece, discontinued". Although these were on listings for individual machines with specific defects, so maybe it's just a translation error

[@Xoferif]

Interesting stuff! Does anyone have a link to the schematics? I've had a good rummage around and I can't find any.

[@HappyLittleDiodes]

You can see the link in the video at the beginning!

[@Xoferif]

@@HappyLittleDiodes Doh! Clearly I should've drunk more coffee today. Many thanks!

[@budgetmerch]

@@HappyLittleDiodes It's dead.

[@kurbeco]

uh oh, another thing I need now :D

[@HappyLittleDiodes]

Let me know if you get one!

[@preferredimage]

Not actually found anything that uses the 512k you find in pentagon machines as yet. if anyone has any pointers to great amazing demos that use 512k I'm all ears!

[@HappyLittleDiodes]

Check out the Simon's Cat demo, at the end of the other nucleon build video on this channel (link is in the description). The demo is called "butterflies" and requires 512K, although it may not use the full 512

[@peddersoldchap]

Is this pcb available for sale? Can't find much about it on the web...

[@HappyLittleDiodes]

He puts them on eBay from time to time either as kits, assembled, or assembled with bugs. You can see them in completed listings. I believe he also has listed them on sellmyretro

[@peddersoldchap]

@@HappyLittleDiodes Ta!

[@budgetmerch]

The pdf link at the start is dead - is it now gone?

[@HappyLittleDiodes]

Drop me an email I'll send you a copy. It's in my channel info.

[@budgetmerch]

@@HappyLittleDiodes Thank you so much - just emailed you. 👍

[@jeffm2787]

Flux, flux, need flux. No but really you need Flux.

[@kyorin6526]

Flux, flux, and more flux...

[@Zanaz728]

What is it actually 🙄

[@HappyLittleDiodes]

It's an evolved version of the ZX Spectrum Pentagon. A clone of the ZX Spectrum.

[@Zanaz728]

@@HappyLittleDiodes thanks for the reply♥