C64 mini keyboard kit – keycap butchery success!

Have been promising a long time to do this, so finally took a few hours to butcher another mini!

Some views are excellent
Another great view
And the worst view

As you can see, for the most part, it’s pretty good, but NOT perfect

what I’ve discovered…..

2 part epoxy works best

Each keycap row is a different depth – the top one needs the least glue, row 3 the most

My errors here. I used a hard plastic glue from Bostick. it doesn’t grip well enough on the top of the keyswitches. I glued everything, waited a few hours, half the keycaps didn’t stick

glued the rest, waited, half again didnt’ stick…rinse and repeat about 6 times, adding more glue till finally they all stuck.

The 2 part epoxy stuck fast and hard! – but I used too much.

The repeated adding of more glue caused the multiple key levels you can see in the picture

I’ll try one more time I think!

The Blinkenator Part 32768

With a successful 2nd Kickstarter – The Spectrum Next will have between 8,000 and 9,000 users.

Lets Dream a little and imagine a Bright world where all the users have a Super LED Blinkenator 2000 installed….

9000 users = nearly 40,000 inserts to be made!.

lets say just 10% want the blinkenator, I still have to make nearly 1000 of the things.

I’ve been researching a little and identifying bottlenecks to SUCCESSFULLY produce and deliver my board in those quantities

There’s some scary numbers!

So, I’m now pressing forward with TWO designs. one design, the one you’re all familiar with, suitable for small time production in small batches here and there on my weekends, only ever endeavouring to sell maybe a 150 units ever

and the second, a ‘mass produced’ item that requires minimal ‘hands on’ time from me to deliver, but will require some significant outlay up front.

The pictures above are a first run result of my Design For Manufacture for the inserts….A different injection mould, possibly 2 parts, maybe 1 and using a flexible PCB!

some key notes……..

Advantage – no connector soldering needed on my part – currently I’m soldering 16 cheap ‘bridges’ to each main board. with this insert, someone will be soldering 8 SMT FPC style connectors

Advantage – it’s likely that this design will be easier to make ‘injection moulding’ manufacturable. the existing design is tricky, but not impossible

Advantage – FPC connectors are a bit more reliable and easier to use than my bridges for the end user

Advantage – FPC / flexible PCB ‘legs’ on the inserts will mean a little bit easier installation by the end user

Advantage – Uniformity of Light – This type of construction allows for a much thicker ‘top layer’ – which will diffuse the light far more. Also, more of the insert will be better lit up ‘from below’ rather than from the side that i’m currently doing.

Disadvantage – FPC connectors are more expensive

Disadvantage – Flexible PCB’s are more fragile

Disadvantage – Flexible PCB’s are more expensive than FR4 for small quantities, so prototyping ability is very limited. at The quantities I need though, there’s not that much difference

There’s more i’m sure, once the final numbers are ready, I can see if a kickstarter makes sense, it may not be financially viable if the whole thing needs to be sold at £80 each……

if I can get closer to that £50 mark, then who knows!

Spectrum Next LED inserts…..Big steps

I’ve been updating the Dev group on facebook more regularly than here

Progress has been slow but constant!, the new Jumper method of getting the LED inserts to connect to the controller works well, if a little fiddly. I think there’s some changes I can make to allow for an easier installation experience.

A big milestone also – The BETA hardware is at such a point now that i’m happy to send it to the core Dev team for actual installation inside a Next….err, except they can’t have the bottoms on as the USB cable doesn’t fit, D’oh!, another re-design needed!

AND – software – My Arduino code’s finally quite stable – Also, from the Next side of things – the i2c code is great – it runs well at 14MHZ, allowing for some interesting sequences on 8 segments…..I’ll start uploading BASIC programs in the next month or two.

Also, a kind of fork in the road….

Throughout this project, I’ve had an end goal of maybe 5-10% of Next owners owning a Blinkenator. at 3000 Nexts, that’d be maybe 150-300 devices sold over a year or two, making my beer money fund quite happy

Things recently changed……and have made me realise that I’ll probably need to step up my game a little…..

The Latest Kickstarter………. https://www.kickstarter.com/projects/spectrumnext/zx-spectrum-next-issue-2

Means that now, there’s over 8000 Nexts in the wild!.

Assuming the same targets, I’d now need to manufacture between 400 and 800 devices…

May not sound much – but at a top level, for just 800 units…….that means some big numbers…..

sourcing 3,200 Plastic inserts….

Sourcing 26,000 LED’s

and with big numbers comes Big Money….and long lead times.

IF someone landed me with an order for 800 Blinkenators tomorrow, at (say) 45 minutes per board, I’d need 600 hours to complete the order.

I have a day job that demands my attention for 160 hours a month. Wife and kids that demand me for a further 80 hours a month…then there’s the whole sleeping and eating thing..

It’d take me a year to be able to fulfil that order 😛

So, the fork in the road……….I may need to do my own Kickstarter!

I’m investigating larger scale manufacture – Full PCBA including through hole, better DFM and Plastic Injection moulding.

All that costs big up front ££…..hence the Kickstarter………is my 5-10% adoption figure massively optimistic. Is it woefully inadequate?

To have any chance at a successful Kickstarter, I need to turn this hobbyist , good quality (7/10, could do better) project into a slicker experience, a better presented finish and professionally produced, not at my dining room table package that would obtain a Crash Smash award, a solid 9.5/10 experience. I KNOW I’m capable of creating the hardware (i’ll learn the software). I’m genuinely uncertain at this time if I would be able to DELIVER that package.

Saying that, I know my limitations, I have a grasp of the fundamentals and i’m costed to the penny for small batches.

Extrapolating that upwards and figuring out where costs stand for different adoption rates is my focus now the BETA 1 boards are ready.

If 30% of Next owners buy this thing, that’s 1800 hours of ‘work’ to do. That’s a FULL TIME JOB!!

scary isn’t it. I have to create budgets that allow for an employee!!

The Beta Board – installed
close up of the new connection method for the LED’s
another closeup
A big milestone – SIX Beta Boards
8291 times a routine ran from Basic without crashing at 14MHZ!!

C64Mini keyboard kits shipped!

First batch of 15 kits shipped!

Postage on most was actually slightly cheaper than last time! But the two heaviest ones were more, the largest one was quite a bit more than anticipated…so it all averaged out ok…

One repeat customer has a couple of freebies, only one assembled this time!

Also my first ever customer finally will have a spare kit and some stuff to practice with 🙂

Next small batch is coming as soon as the 20cm USB cables arrive.

If you want a kit without the short, tidy looking USB cables then shout and I’ll do a small discount 🙂

Amusing story and reversed switches on the C64 mini keyboard kits

Correct orientation of the switches
Correct orientation from the top. (Except the shift lock…oops! That’s why I put extra switches in :-p)

A funny story about multi sourcing components and the importance of testing before shipping!

I used a supplier on Aliexpress to purchase a few thousand switches in a few orders over a few months but their prices went up quite drastically after the last order (doubled!!) they weren’t the cheapest to start with but were reliable and friendly, worth the extra ££

I found another supplier who did a good deal for a full bag of 4000! Ordered them and waited, very quick delivery and friendly also (will buy again!)

I built my first test new keyboard with the new PCB and switches

It didn’t work. Well, actually, it did! Work perfectly…but in reverse :-p …..

If you mashed every key simultaneously then only released the key you want to press….it worked!! Yeah, the supplier sent me 4000 ‘inverted’ switches! My fault for not checking prior to ordering, they ‘look the same’ so ‘must be the same’ was a wrong assumption on my part! (At least they all weren’t the shift lock type!!)

It’s a VERY easy fix though (found after several panicked hours of testing and building Keyboards)…rotate the switch 180 degrees and it’s perfect!

In each kit I’ve included a small errata note and list of basic instructions to help. It’s an annoyance but for you guys it really just means the silk screen doesn’t quite match the switch orientation so just ask first. Look at the pictures and of any doubt, email/messenger/twitter/Reddit me 🙂

C64 Mini Keyboard kits, ready to go :-)

I’ve a small batch of 14 kits assembled and ready to post 🙂

The ‘slightly open’ ones are waiting their 3D printed inserts which are taking about 6.5 hours for 3 right now 🙂

Send me a message if you are reading and would like one.

I have enough parts to make 50 kits all up, except for the USB cables – I’ve lost a large bag of them somewhere so have ordered more 🙂

The Spectrum Next LED Inserts

The spectrum Next has a new Kickstarter! Currently sitting about 1.2 MILLION!!

And, the professionally produced LED inserts PCB’s have arrived at Bleugh.Biz HQ

Tiny! That’s a British 10p
The Resin printed plastics fit perfectly

One slight error on my part, I forgot to ask them to send individual pcb’s, meaning I have to hand cut out 600+ of them :-p

But, they Fit and give me back a tiny amount of space for me to make the walls of the inserts thicker…

Happy!

The Super LED Blinkenator 2000 progress…

This is the inserts being ‘mass produced’ at a PCBA manufacturer:-)

I’ve purchased a reel of 5000 LED’s and paid for them to make and solder them to as many boards as they can…which should be about 620 odd

Continue reading “The Super LED Blinkenator 2000 progress…”

C64 Mini Keyboard kit – a successful user :-)

By reddit user mfriethm. Looks amazing

I sold the first batch of kits mostly on Reddit

Over the past few weeks they’ve been making their way around the globe and I’ve had a lot of happy reports back

Today, Ive been able to relax finally, the Mould works 🙂

Reddit users fantastic gallery

He’s done an amazing job using a silicone mould!

The workflow – make a mould of your uncut keybaord

Cut the keys out, tidy them up

Place keys in mould

Put glue in keys

Place keyboard on top and use screws to align

Voila!

C64 mini Quick doodle for the USB hub mod

Had someone ask, so here’s a quick and rough explanation

You need to make SIX solder connections

First, lift the centre two pins of USB1 on the mini

Second, cut off the plug and solder four pins from the USB hub cable to the bottom of the USB1 connector pads on the PCB

Third, cut off the mini USB of the longer USB cable and create a bare end. Solder two data wires to the lifted pins on the mini’s USB connecote

This then attaches the USB hub in full to the minis processor

And just uses the physical connector on the mini as an extension of one of the sockets on the hub!

Assembly of the C64 Mini working keyboard kit! – PICTURES

Follows a couple of pictures of the install, I’ve also put a couple of videos up on youtube. More will follow

DIODE orientation. Note, make sure they’re all the same way round. One here isn’t!

I’ve put some videos up on youtube about the assembly process – the playlist is linked below

Putting the switches in Wonky for the first round of alignment (smt diodes hand soldered on the original prototype)

Make sure you solder the arduino headers on before you get this far with the switches

Back of board showing Diode legs clipped and only ONE switch pin tacked per switch

USB HUB TO FOLLOW – Pictures shown in blog previously if you need them quickly

Assembly of the C64 Mini working keyboard kit! – TEXT

Some quick steps right now – photos to follow.. Suggest have two tabs open, this one and the other PICTURES tab for reference

Some videos are up on youtube also

Link to Youtube videos

SUMMARY- SOLDER PARTS ONLY IN THIS ORDER

DIODES

ARDUINO HEADERS

SWITCHES

DIODES

  • Cut one leg shorter on the diodes – Use scissors . About 1-1.5cm is good
  • bend the short leg side to a right angle
    • Note the orientation of the diode – The F Key diodes have a diode picture on them. The white bar matches the location of the black bar on the diode.
  • put diode in holes and bend slightly to lock in
  • repeat for all diodes
  • Solder all diodes
  • clip the excess legs back
  • you have a few spare diodes so don’t be afraid to experiment on one or two to get the right bend / fit

ARDUINO HEADERS

  • Probably best to solder these in now before you forget
  • I’ve found it useful to PLACE the arduino on the headers (DO NOT SOLDER YET) so it keeps the headers parallel
  • Make sure the black part of the headers is on the underside of the PCB
  • Solder one pin of each header
  • remove arduino
  • finish soldering

SWITCHES – STEP 1, JUST TACKING IN PLACE

  • Pay attention to orientation
  • don’t worry about straightening the switches at this stage, the goal is to just ‘tack’ them in with a single solder blob to hold them in place. They can be wonky, it doesn’t matter.
  • DO NOT SOLDER MORE THAN 1 PIN OF EACH SWITCH IN ONE GO
    • The switches are easily heat damaged – they become ‘sticky’ and no longer move smoothly if the plastic is melted due to excessive heat. During the entire soldering procedure for the switches, do ONE leg, move to the next switch. when all are done, move back to the first switch and repeat.
    • I’ve damaged only 2 switches this way soldering the prototypes but it can happen if you’re not careful
    • Note that the white part of each switch is asymetrical. One side has a ‘dip’ / inset which guides the switch up and down. the other side is smooth
    • there’s a marking on the PCB to represent this dip / inset.
    • ALL switches go the same way
  • Get a sheet of paper
  • Insert the top row of switches into the PCB
  • Place PCB on sheet of paper and fold paper over the top, tightly
  • flip the PCB over
  • hopefully all the switches stay in place
  • Solder just ONE leg of each switch – any one – say the top right
  • Repeat for Row 2
  • DO NOT FORGET TO SOLDER THE ARDUINO HEADERS IN PLACE
  • Repeat for Row 3
  • DO NOT FORGET TO SOLDER THE ARDUINO HEADERS IN PLACE
  • Repeat for for row 4
  • (Hopefully you didn’t forget to solder the Arduino headers in place?)
  • and finally the space bar

SWITCHES – STEP 2, Straightening

  • This is probably the most important step to getting a good looking keyboard with all the switches aligned. Spend some time getting this right, you have a handful of ‘spare’ switches so now’s the time to make mistakes and fix them whilst there’s only a single solder blob on them
  • I’ll post a few videos shortly but there’s a technique.
  • Hold the board in the air
  • Use your index finger to push in, and slightly down on each switch whilst soldering the previous blob. The goal is to move the whole switch slightly so that it’s slightly at the top, or the bottom of its footprint.
  • when you melt the solder whilst pushing in and down, the switch will move slightly, sometimes you’ll hear a little click or snap as the solder melts
  • repeat this for each switch, pushing in and down slightly – when you look at the final position, there’ll be some of the pad visible at the top of each switch
  • NOW IS THE TIME TO TEST EACH SWITCH FOR SMOOTH MOVEMENT
    • of the 5 keyboards i’ve soldered, I’ve had two defective switches, this is partly the reason why there’s a few extras in the kit
    • of the 5 keyboards i’ve soldered, I’ve broken 3 switches by either over-heating, or trying to remove after putting them in backwards. unless you’ve got a hot air gun, they’re tricky to remove intact, hence check NOW whilst there’s only one solder blob!
  • When you get close to one side of the keyboard, you’ll have to fiddle a bit to keep pushing the switches in the same direction. I’ve found that changing technique a little and ‘flip’ the board lengthwise works. hold the board against yourself and use your thumb to pull the switch down instead of push
  • repeat the alignment technique for ALL switches!

SWITCHES – STEP 3, Final soldering

  • This is the easy / relaxing bit!
  • DO NOT SOLDER MORE THAN ONE LEG OF EACH SWITCH AT A TIME
  • do it by rows, clusters, however works for you, but here’s what worked for me
  • Solder ONE pad of each switch, then move to the next
  • once all switches are done, start from the beginning
  • Solder another pad, etc etc
    • A SMALL CHEAT – You only actually need to solder 3 points. Two on the ‘bottom’ of the switch – these are the electrical contacts. ONE on the ‘top’ – this is for mechanical stability. As you look at the keyboard, the bottom two pins are the important electrical ones. Pick any on the top
  • on my prototype, I found soldering all 6 pins tiring, so on my second version I just soldered 3 and it worked perfect. Up to you, but DONT SOLDER MORE THAN 1 PIN AT A TIME

Arduino

  • Note the orientation of the Arduino by the Small USB socket and a mark on the PCB. Also the silk screen on the PCB will match the letters on the Arduino.
  • these need a little more heat to solder to the pins

Finished Keyboard!!

The Hub

Zx Spectrum Next Blinkenlights …inserts arrived!

Not a huge post this one, just a quick couple of photos

A bit more diffused! Still a bit more work to do
It’s tiny! That’s a British 1p. 8 LED’s
Lots of hand soldered inserts ready for the dev boards.

The inserts fit perfectly into the case also. I’m going to experiment a bit with diffusion methods, surface finishes and colours.

I picked up about 80 of the inserts so plenty to experiment with and get the dev boards done

C64Mini working keyboard – The Butchery Part 1

Time’s progressing and it’s still taking a long time to obtain a satisfactory print of my CAD keycaps. Some quotes have come in and…they’re quite a bit.

so, time to change focus for the short term to let me actually play games on the mini with all the keyboardy goodness that a working keyboard will allow

So, on to some butchering

The Plan….create a plaster of paris negative of the original keyboard – to hold the keys straight when attaching them.

Step 1 – Print out the case design from my last post

Fits like a glove……..or does it?

Step 2 – realise that I’m making a NEGATIVE and the keyboard needs to sit INSIDE the box, ‘upside down’ Redesign and re-print…

Better

Step 3 – Coat liberally in spray oil… Wife wasn’t too happy that I’d used her pricey artisnal olive oil from our trip to Italy, nothing but the best for my Mini though………

Step 4 – Knock up a batch of pancake batter Plaster of paris…About 50 grams of powder and 60ml water worked for mine….not too viscous.

fill the keyboard case just over 1/2 way to measure what you need

Step 5 – Fill up the mould

Screw on the keyboard – making sure the keys are aligned and straight with the F Keys and wait overnight…

Use the holes either side to top up the plaster so it overflows a little

Give the whole combo a dozen or so short sharp drops / knocks on the table to free up any air bubbles

Mmmmmmm….Keyboard Cake?

£40 well spent and a happy Hamster, a Wheely good use for a 3D Printer

Back a couple of years ago, I lucked out on a facebook marketplace post. Someone was selling an unassembled 3D printer kit, that was tatty and had missing parts………Woo!

I did a 30 mile detour on my voyage home from Wales and grabbed it. excitedly pulling all the bits out of the oversized, filthy box and….Putting them into a rather smaller, cleaner box for a couple of years whilst not doing much with it.

Well, today, that £40 investment paid off.

by hacking a chunk off the 8mm threaded rod, using a few bolts and washers, and a quick mod using a spare Hama-beads square that we had lying around, I was able to fix the broken hamster wheel!

or, in other words, I’ve massively over-engineered a fix by butchering a 3D printer (kit).

On the plus side, I’ve a happy hamster AND saved £2.87 by not needing to buy a new one!

Also, It’s gotten me thinking….HAMSTER STATISTICS.

How fast can they go?, how far do they run?

I’ve just picked up some of these – Hall effect sensors

i’ve already a handful of Arduinos and Raspberry pi’s. ………..

Something Different – a New laptop – Ryzen 4800U – A BEAST

I gone and got me one of these…..

My first new laptop in over a DECADE…

https://www.lenovo.com/gb/en/laptops/ideapad/s-series/IdeaPad-5-15ARE05/p/88IPS501393

A Lenovo Ideapad 5 15″

and it cost me pretty much bang on £500 GBP after discounts and cashback! (Thanks to HotUKDeals – Link here, well expired by the way)

What’s special you ask?, Why now, why not let my perfectly servicable ASUS Republic of Gamers Original I5 based laptop keep ticking for another few years?

Well, A Processor / APU Called the Ryzen 4000 series, codename Renoir by AMD caught my eye back late last year

IT’S A BEAST

I purchased a variant of the laptop with the Ryzen 4800U processor inside.

One of the first things I did was to run a Benchmark – This one

The result – Just a shade under 20,000 CPUMARKS

…………a laptop, costing just £500 outperforming Desktop processors that cost more!

This £500 laptop benchmarks in the top 11% of processors globally! it’s faster than almost 90% of other computers out there……..

And, here’s the Cinebench Benchmark. Note that it’s just above the Xeon E5-2697 v2 which still costs £200 on eBay

The i7-7700K is an interesting one though. This processor’s been a ‘gaming go-to’ for performance and overclockability for a few years now , that’s another £200 eBay processor

Something more modern to compare to?

This one’s 488 in single core and 3925 in multi-core

Go over to the Cinebench website and see –

Sort by Single score – sort by benchmark

The closest intel processors are the

i5-9600K (about £200) at 481

and the

i7-10700k (about £400-£450) at 497

Now for the Multi-core

The closest intel processors are the

i7-8700K (about £300-£400) at 3793

and the

i9-9900K (at least £420 ) at 4914

now, one more set of benchmarks – Here – (CPUBENCHMARK.NET)

Scroll down to 19884 – See just what processors are sitting in the same area – what their retail price was! – this processor sits at exactly the same position as the intel i7-10700KF

A 125W DESKTOP processor that costs £400 on its own on ebay right now. Add all the other stuff needed to make a fully functional PC and you’re getting close to a GRAND on a DESKTOP!

In summary – I’m besotted….This laptop’s happily rendering in REAL TIME what my old laptop took tens of minutes in Fusion360

if you’ve been holding off buying a laptop, you really can’t go wrong with the Renoir series of processors.

and, for games – seems to run Fortnight,Starcraft 2, and a few others just fine at maximum settings! performance apparently is about the same as the Geforce MX250 which isn’t sloppy considering this is integrated graphics and has just a 25W TDP when under extreme performance. The MX250 graphics card has a 25W TDP on its own for this benchmark!

Fawning over, normal service will resume shortly 🙂 – in the meanwhile, ask away any questions, happy to answer them

Spectrum Next – controller Board Iterations, 3rd and counting

I Purchased 10 controller boards with the SMT components ready assembled There’s a few small bugs……But, that’s what prototyping is for.

First major annoyance – I’d goofed and left VCC on the arduino as 3.3v in the schematic. so, the board wouldn’t power up inside a next. Quick fix is to short RAW – to the VCC pin on the Arduino

(RAW is a 5V OUTPUT when plugged into USB, or 5 and a bit Volts INPUT to power the Arduino)

This has the potential downside of back-powering the Next via USB via the 5V Line when it’s sitting inside a Next and someone uploads a sketch

Another change needed – The Arduino’s USB port fouls the case when fitted inside. With a USB cable in, the lower part of the keyboard inlay blocks the port. – it’s ‘just’ about bodgeable however if you really wedge it in there. But, not ideal So, i’ve tried with soldering the arduino ‘upside down’ on the wrong side of the board – that seems to work. The board’s mounted just far enough ‘up’ into the case that a USB cable can sit under it.

For the production version i’ll re-arrange the board completely

Another further change –

Removing the RAW pin entirely from the Arduino and shorting the Next 5V directly to the VCC pin on the Arduino

That’s about it for these pictures,

From top to bottom –

Original board – has a resistor bodged in and the RED led installed on the wrong side. Also has my ‘impossible to solder straight’ PCB fingers.

Third board – upside down mounted arduino with missing RAW pin

Second board – my ‘go to’ working one right now – also has the first run of my ‘quick fit’ connectors……i’ve done about 20 cycles of inserting now and they’re still working!

Spectrum Next Blinkenlights…More progress Insert PCB’s and first (second) light!

Now with 8 LED’s worth of goodness!

Due to my previous goof-up of having made the old LED insterts ‘backwards’, I designed new ones!

They’ve arrived and are all round much better

  • Slimmer – just 2.2mm wide
  • 8 LED’s!

Here’s what they look like – the features are a bit too small for JLCPCB to handle on their mass production – their mill uses a 1mm bit – guidelines are minimum of 3mm between milled out slots

I’ve ordered 50 of these – should be plenty to fill up the 10 prototype control boards i’ve gotten made and leave a few over for experimentation / errors

There’s a small problem however with mousebites this small – each board takes a good five minutes or so of dremmeling to get ready!. I can do about 7 boards to a charge of my battery powered cutting tool….I’ve ordered 50 prototype PCB’s so that’s lots of minutes of work ahead! good thing we’ve a handful of N95 facemasks picked up from back in March just as the world went loopy!

Here they are in all their glory, powered up the RIGHT way round on a controller PCB.

I hand soldered all 4 of them using some new (expensive) solder paste,d 3 worked first time! the last one had two LED’s mis-aligned…Quite a good improvement!

Each insert so far on the prototype is taking easily 20 minutes from receipt of parts to working device. Each new controller PCB is taking over an hour of soldering and wire cutting for the quick contacts. That should come down quite a bit once i’ve figured out a process.

First Light INSIDE a Next!

Yeah, spot the mistake 😛 Still, quite chuffed – these are powered up and working INSIDE the next! –

There’s no control YET – this is just a single routine that runs upon powerup in the Arduino….

IT’S ALIVE!!

And, just as a final superb moment – look at these results of a quick i2c Scan (there’s a lot of numbers due to using an HDMI monitor)….That 3rd Device at address 0x45 – That’s the Spectrum Next Super LED Blinkenator 2000 just waiting for a .DOT command to control it 🙂

C64 Mini Keyboard Progress..

Rev 2 PCB’s have arrived – 15 of them!

Now waiting on enough Arduino Pro micros and switches to start making kits up!

Each DIY kit will probably contain the following – i’ll firm up with pictures once i’m done test populating a rev2 board

  • 70 Standard switches
  • 70 Diodes – Through hole (possible SMT option also depending on price)
  • 1 USB Hub
  • 1 PCB – Rev 2 or later
  • 1 USB cable
  • two small pieces of heatshrink tubing
  • a couple of pieces of wire
  • 1 Arduino Pro micro – Pre-programmed with QMK firmware and custom Keymaps
  • Some instructions
  • a set of FDM – Filament printed keyswitches – These probably won’t be ‘perfect’ so i’ll be chucking them in as effective freebies as I won’t be releasing the keycaps as a digital file.

About that last part – I’ve spent countless hours on creating these keycaps, and still have more to go. I’ll eventually release them as a Digital file, but for now, you’ll be able to at least use the freebies to see if new keycaps are for you.

If you wanted a professionally printed set, i’ll be arranging something with a printing bureau somehow… It’s also likely i’ll be able to source reasonably costed SLA resin prints of these…watch this space

And for the money shots…….I’ve finished the top row of key text!

Now I’ve gotten the first row done, the next three should be significantly quicker.

The text is recessed into the key by about 0.4-0.6mm – between 2 and 6 layers of 3D print, not really enough to be clearly felt – but enough to be ‘seen’

After that, there’s the optimisation for printing – Filleting the edges – trialling depths and generally finding out what actually works, looks and feels good

Spectrum Next Blinkenlights – PCB’s arrived and First Light

A christmas tree creation for a JLC PCB competition

and i’m well chuffed to say – they’re almost alive!

There’s a few teething problems however,

My ‘excellent’ idea as can be seen on my last post – https://bleughbleugh.wordpress.com/2020/05/19/spectrum-next-light-strips-more-first-light/

to use some PCB grounding spring contacts to provide a quick fit connection didn’t really pan out – the contacts simply didn’t solder on easily, too difficult to align correctly and quite weak – I tore a few pads off trying to get them aligned and correctly ‘grippy’ on the insert.

multiply that by 16 each board – the first one took me about 2 hours to get to be in an ‘ok’ state – Not really acceptable for a mass production product – not that this’ll be mass production but I’d rather not spend half a day on each of these getting them ready for sale……..

The second slight issue – See the photo below

The PCB is laid out on top the next board in the position it’ll be installed in.

There’s a prize for someone that spots the goof-up

Have a further look at the PCB powered up………..

First Light! – The board works 🙂

Yeah, I got the inserts ‘back to front’ – That’s the result of working on a bottom mount PCB from the bottom…….

There’s two ways I can fix this

Simply rotate each LED by 180 degrees on the PCB and install a bodge wire to swap the input and outputs around………

OR….

I can simply re-design the LED insert and improve upon it!

a few reasons to re-design,

The first 6 LED version still has a bit of point brightness – I fear that even with the SLA printed inserts it won’t be diffuse enough..

Some statistics

8 LED’s – This should spread out the light more, reducing the hotspots a bit

0.4mm Slimmer – this lowers the LED’s further into the case, allowing much more plastic to sit above. I’m hoping this will de-focus the light more

Reversed connections to match the reversed controller board!. reversed is the new non-reversed now 🙂

New insert PCB’s are on order and should be here in a couple of weeks, I’ve bitten the bullet and ordered FIFTY….Also a few hundred more LED’s and a large tube of solderpaste.

Doing these first 10 dev boards is going to be fun – 320 1.5mm LED’s to be hand soldered!

The Controller board fits inside the case almost perfectly

I’ve slightly offset the J15 connector on my PCB to the one on the next. This offset gives a lot of friction, but needs some long term testing – the standard header I installed on one of my boards seems to work well as a friction fit. BUT, i’m not convinced that 32 LED’s, each pulling 5-20mA, (depending on which datasheet I refer to) – or between 160-800mA total depending on how I end up setting the brightness…..800mA is a LOT to pull

I’ve purchased a new gadget – A Riden RD6006 Benchtop ‘power supply’ so once i’m set up, i’ll charaterise the LED’s and current draw to set the software limits appropriatley

I doubt i’ll take nearly an amp on this board 😛

One further small mistake on the dev board –

That 3V3VCC – it should say just VCC

When originally designing this controller board, I was to use a 3.3v Arduino to make it compatible with the Next’s 3v3 i2c.

For a few reasons, I’ve changed to using a 5V arduino and putting on-board a level translator device – this gives a 5V buffered i2c output that anyone can easily plug into

I forgot to change the net names….The board still ‘thinks’ the Arduino is either powered from RAW (it’s ‘unregulated input’) or 3V3 VCC…

The RAW input drops a few volts through a voltage regulator on the arduino to give the arduino a nice regulated 5V.

The next output is 5V….it’s not enough to power the Arduino through the RAW pin…

Took me quite a while – and a bit of soldering hackery to figure that one out as the speccy picked the board up perfectly when patch wired in place..

USB powered, it works perfectly

in the Next it doesnt….

The fix – I think I can just short the RAW pin to the unconnected VCC pin on this first batch –

and, finally

See that i2c device, found at address 0x45………..That’s the Blinkenlight 2000 PCB :-), alive and inside the Next!!!

C64 Mini – Keyboard – More CAD…

Had quite a few odd issues with my old f1 key and trying to make a full keyboard from it using the same technique

…The main problem is that I can’t really remember what I did and in what order, and there’s some odd non-parallel lines that really should be – so I’ve started again from scratch

Turns out also that there’s a few types of keyboard out there, the C64-Mini isn’t quite 50% of the keyboard i’ve been referencing

Differences are only minor – BUT it does mean that an exact 50% scale won’t fit

So, Firstly I start with the side profile sketch again.

My revised Side View – I’m ignoring the space bar right now as it’s ‘different’

C64 Mini Keyboard – Some progress!

Not much really – Shift Lock keys just arrived off the slow boat. The pinouts are confirmed, I’m going to hit ‘go’ to manufacture after another quick check on the PCB

Also, from a bit of researching, i’m not so sure the Diodes are needed.

I may have to make two batches of board, one with, one without

 

Spectrum Next – Blinkenlights Part 3

LED Strips!

https://www.alibaba.com/product-detail/Arbitrarily-Cut-Ultra-Narrow-Board-1_62369796191.html?spm=a2700.12243863.0.0.6d933e5fkghAZf

They make TINY super thin LED strips –

tiny strip 2

Great, I could shave down the underside of the insert and then I could shove a bunch underneath the insert –

The problem……….

tiny strip 1

The Pixel density isn’t so good 😦

the Inside radius of the arc of the insert is about 17.1mm…see picture below…

That gives us a total circumference of about 108mm for the circle. hat gives us about 27mm for a 90 degree sweep of the arc. There’s actually a bit less than 90 degrees, so lets say that we have 25mm of length along the arc where the white dots are.

Spectrum Next LED Insert - PCB First Test

25mm of length and LED’s spaced 6.3mm apart only allows us 3 LED’s along the arc……and based on previous experiments, that won’t be enough to give a nice looking line of light……

I’ve messaged the manufacturer to see if they can do anything with more LED’s – at least double, maybe 8 for the 25mm length about 1600 per meter ;-)…who knows!

 

So, onto another idea……maybe a small PCB?

Looks like I can probably fit a bunch of 0603 LED’s inside!

Some quick outlines in EASYEDA

To the left is a bit of a trial to see if I can maybe get a Flexi-PCB in alongside the Insert….and another trial spacing to see if I can maybe get some degree of control of the LED’s – instead of a long block of 6 or 8 LED’s in parallel, why not 3 or 4 pairs of LED’s?

That way I can have a winking left/right status and a solid status…you could get some very basic animations going on all 4 LED’s split into 2 segments each – 8 individual lights…

 

 

Speaker enclosure dimensions – oops

Folded - Oops

The pipe with the new 53mm straight lengths comes a little short of the planned box enclosure end……

I’d calculated the ‘missing’ 57.5mm length based upon the centre path of the diameter  having a diameter of 95mm……

The pipe itself has a diameter of 85mm

So, the actual pipe itself will need an additional 42.5mm either side of the path it follows………..

Which means, a new sketch………Something like this.

 

folded6

  • R47.5 is the 95mm diameter of the centre of the pipe
  • R90 is the outer diameter of the 85mm diameter pipe
  • 10 is the thickness of the speaker enclosure

Finally, we have at least one outer enclosure dimension sorted! – 200mm – Err, that’s a bit bigger than planned! – The speaker itself is only 98.2mm diameter……Looks like some more iterating needed, BUT, now I understand the dimensions, I can experiment a little with the Tube’s cross sectional area and therfore diameter…….

In hindsight, the speaker enclosure dimension was fairly obvious…….

  • enclosure thickness ( 10mm ) +
  • Transmission Line Diameter ( 85mm ) +
  • enclosure thickness ( 10mm ) +
  • Transmission Line Diameter ( 85mm ) +
  • enclosure thickness ( 10mm ) +

= 200mm!

The smallest enclosure possible has a Transmission Line area the same as the speaker – i.e.

  • SD of 28.3 gives a Diameter of 6cm….
  • 10mm + 60mm + 10mm + 60mm + 10mm

Smallest possible size = 150mm

More fun to follow………..

Lets look

 

Something new backed! LEGO sorting :-)

Piqabrick

https://www.kickstarter.com/projects/piqabrick/piqabrick

Sorry no updates of late, real life’s taken over, haven’t used the printer in some time.

Have found a new way to procrastinate though whilst actually doing something useful….And plan a future build of a fully automated LEGO sorter!!

(Gotta use up them spare 3D printer bits somehow!)