Please be standing for the SX20
Who else would build a truly portable Commodore VIC20 than the chap that made the C64p?
For those of you not playing along at home, back in 1826 (shortly after tea time, but before Eastenders).. I ‘knocked up’ a bunch of C64p’s made from old 7″ craptops, custom PCB’ery.. and of course, the right flavour of C64DTV.
Not only were the C64p’s super cool. But they were in fact how and why ‘The Future was 8bit’ happened. You see, all those Millions of years ago, NOBODY was selling ‘SD2IEC’ or the like. Maybe you’d find a blank PCB via a seller on Ebay, but it really was a completely different ‘Retro Landscape’. Anywho, to cut a long story short, I used my overdraft to pay for some custom PCB’s and a few parts. Sold the left overs on ebay.. And ta-da all these years later I’m still flogging 8bit kit from a silly little island somewhere off the coast of Europe.
Anywho, back to the SX20. The SX20 idea sprang into my mind that day I bashed my leg into yet another busted up SX64 (In my kitchen IIRC). I quite often kid around about low serial number donors in my builds.. But this one(s) really were scrappers. One looked like it had been recovered from a car crusher, the other was a mix of broken bits. These included a ‘modified’ disk drive (see broken) a broken monitor (see modified) missing handle, smashed keyboard. Basically your average ‘Grade A’ SX64 ebay listing.
Maybe it’ll come back to me, but I don’t know how I managed to have more SX64 than people with a lot of A4000’s would consider too many but late night ebaying used to be a fun thing. Let’s leave it at that.
Anywho, lets get on with this shall we. The first evidence never ending project are pics from 2018.
So, lets delve into all these old pics and try and make some sort of timeline.. and all this while I try and get the SX20 finished. Afterall, it’s been fully working for years and years.. but I feature creep & my own spare time (something I don’t have a lot of coz RL and TFW8b) gets in the way.
BTW, do keep coming back to this page for updates, it really will take me a while to get all this sorted and by the end of it, I really do want my SX20 to be finish FINISHED!!
GET ON WITH IT..
Ok Ok, but be warned.. If you start a project in 1826 then try and to a write up on 2026.. well you will have forgotten things.. and you may well have forgotten to take ‘important’ pictures.
So what I’m probably going to do (for the most part).. is show you pics in the order they were taken and try and join the dots with waffle on the way.
SX20 Pic 1 - 21 Dec 2018 - An scrapper Commodore SX64
No1. The Larch – It’s 21st Dec 2018 and this is one of the donar SX64’s
SX20 Pic 2 - 22 Dec 2018 - SX64 Monitor PCB
Science says it’s day two of the SX20 build.. And it looks like I’ve harvested a monitor PCB? Either that or I’m just eyeballing the PCB as I know how bad SX64 Monitor 2 is. Yeah, it’s that!
SX20 Pic 3 - 22 Dec 2018 - Dust, anyone.. No? Dust..
Oh this pic will go down well, yes it’s the infamous SX64 that propped an door open for One Million Years!
And for those playing along at home, it was savoury with a nutty aftertaste 😋
SX20 Pic 4 - 22 Dec 2018 - Ah yes, el'dusto has been 'modified' (see broken)
Yep it all makes sense now, el’dusto was a very brroken SX64.. Monitor, Disk, Disk PCB, Keyboard cable all hacked about.. all knackered and hencely it became a door stop (my bad I know)
SX20 Pic 5 - 22 Dec 2018 - el'dusto innards
Some of the bodgery is obvious (RED taped monitor wiring bodge).. but much of the other bodging / brokenness is still hidden
SX20 Pic 6 - 22 Dec 2018 - Who did this to you! 🥹
You see, I told you these SX64’s were minty mint. So much butchery, even Hilary Bliss would be ashamed. In a previous life, this was the external keyboard interface cable 😭
SX20 Pic 7 - 22 Dec 2018 - The Donor VIC20
It may say ‘not broken’ but IIRC it did have the classic cartridge port fault.
Info on the 74LS138 fault.. Tynemouth Software – The VIC that did not like Cheese and Onion – Tynemouth Software – VIC20 Repair
SX20 Pic 8 - 22 Dec 2018 - VIC20 in the nuddy
VIC PCB removed.. offered up to the SX64 chassis and it’ll clearly never fit.. unless 🪚
SX20 Pic 9 - 23 Dec 2018 - Well that's about the size of it
With the OG SX64 PCB on top.. How many smallers do I have to make an original VIC20 PCB? 2.5 Inch’s and that’s Numberwang!
Yep, I’ll need to remove everything past the 1ft mark.. For those of you with a weak constitution, maybe you should look away now.
SX20 Pic 10 - 23 Dec 2018 - Look away now!
Well how else did you think I’d get it to fit? Mind you I should probably pointed this out earlier. The whole project was supposed to be made with things I have lying around. Otherwise, I may well have spun out a custom PCB.. Anywho, with a bit of help from Stanley, I scored the PCB on both sizes (after clearing the area of components) and snapped it off super close it it’s heart, the 6502 🫨
SX20 Pic 11 - 24 Dec 2018 - Top lopped
It wasn’t just the right hand side of the PCB that had to loose a few inches.. I also had to lop off the top of the PCB and a little from the left hand side. Can you imaging now many traces got ‘interfered with’. That’s right, One Million. But in all (if any) seriousness, I didn’t just lop away.. I used a bright light and documentation to see what I was harming, before the loppage commenced.
SX20 Pic 12 - 24 Dec 2018 - Test tails
Jumping ahead a little. I’ve S-Video Modded the VIC and ‘temporarily’ connected Joystick & IEC for basic aliveness testing.
BTW.. People often tell me to S-Video Mod my VIC20.. not knowing that I do have a modded VIC all along. But rather than trying to describe how its done, check out Tynemouth Software’s VIC20 S-Video Mod here
SX20 Pic 13 - 25 Dec 2018 - Merry bloody Xmas!
Well bugger me, it’s alive! And only 55 seconds into Xmas day! IIRC it wasn’t perfect, I’ve had to remove and reverse the cartridge slot, this and cut tracks meant a bunch more repair tails got added on the way.
SX20 Pic 14 - 26 Dec 2018 - Tidy up and test
Jumping a bunch of wire tiding up pics, this is the new placement for the VIC20 Cartridge port. Upside down, now you turn me, inside out and round and round. And yep. That’s a Penultimate+ #Vintage 😉
SX20 Pic 15 - 26 Dec 2018 - SD2IEC & S-Video connected
Penultimate+ installed, next up it’s time to test keyboard and IEC using an SD2IEC classic 😀
SX20 Pic 16 - 26 Dec 2018 - Alive alive, cockles and mussels oh!
Not a great pic, but yep.. Reversed Keyboard, PU & SD2IEC confirmed as working. Now I just need to cut the PU+ to fit 🪚
SX20 Pic 17 - 26 Dec 2018 - Pinch an inch
If only I ever completed my time machine, I’d know by now that the reversed Cartridge Port and shortened Cartridge PCB would be a thing of the past.. VIC20 Riser Cables FTW.. In about 3-4 years 😉
SX20 Pic 18 - 26 Dec 2018 - Chip tube insulation?
It’s time to squeeze the VIC20 PCB into the SX64 chassis. it’s tight and it’s very metal, so I need to insulate the ends of the PCB.. I seem to remember the keyboard end is super tight. Anywho, I used left over chip tubes 😀
SX20 Pic 19 - 26 Dec 2018 - It fits perfectly 😉
It was a bit of a squeeze, but without the need of lube I managed to slip it in. Mrs.
SX20 Pic 20 - 26 Dec 2018 - The mistreated 115v PSU
Ooof.. Bad things have happened to the 115v PSU. Transformer loose, caps snapped off and glue. Luckily I only need the chassis. But I did put it back together and it now lives in the SX64 scrap box.
SX20 Pic 21 - 26 Dec 2018 - More bodgery
Yes I’ve found more bodgery. This time it looks like someone may have ‘hard’ installed a joystick or extension cable.. and busted a track while they were about it. Mostly sure I’ll never use this in the SX20 due to reasons.. So it’s another part for the scrap box.
SX20 Pic 22 - 1 Jan 2019 Smoke Test 1
Maybe I didn’t take any pics, but all of a sudden here we have the ‘power pcb’ in not charging mode..?
SX20 Pic 23 - 1 Jan 2019 - Smoke Test 2
.. and in charging mode? Something like that 😀
SX20 Pic 24 - 1 Jan 2019 - Just say no
Oh my.. I’ll say this again, the SX20 was born from things I found behind the fridge. I am not proud of this level of bodgery.. but it did work! And some time later this was all swapped out for a less scary PCB!
SX20 Pic 25 - 3 Jan 2019 - Oh look an Plus Deck 2c
I picked up this Plus Deck 2c sans interface cables
SX20 Pic 26 - 3 Jan 2019 - Plus Deck 2c Nude
Terrible terrible things have happened and un-happened to this tape drive. They are quite brittle things, so I spend much of my time repairing it as trying to use it. Spoiler.. it lived 😀
SX20 Pic 27 - 12 Jan 2019 - Little bits
Wow, those SX64 end caps must be worth One Million Pounds in 2026 money
SX20 Pic 28 - 14 Jan 2019 - Time to repair past monitor bodgery
You can’t blame me for this one as this is how one of the scrap SX64’s came.
SX20 Pic 29 - 14 Jan 2019 - It's had it
Yeah, that’s no good.. but I don’t have a spare connector
SX20 Pic 30 - 14 Jan 2019 - But I had an idea
I’ve not done this sort of thing for a while, but you can ‘re-pin’ these sorts of header connectors by inserting pins from something else
SX20 Pic 31 - 14 Jan 2019 - Connector sorted
So I did that, soldered it in and that’s another Job jobbed.
SX20 Pic 32 - 14 Jan 2019 - SX20 is J2 Compatible
In the fuzz of the background you might be able to make out the header I added to the VIC20 PCB to make the video out circuit J2 (SX64 Monitor) Compatible.
SX20 Pic 33 - 14 Jan 2019 - Double Sided Sellotape for speed
This is were things get excellent. Cramming a bunch of lead acid batteries where a big old transformer once lived, using things I found lying around 😀
SX20 Pic 34 - 14 Jan 2019 - It's like it was meant to be!
Sticky tape, foam pads (and some extra electrical insulation).. and I’ve got the feeling that Commodore may have once thought of this!
SX20 Pic 35 - 16 Jan 2019 - 12v Wired up and ready to go
Fused and ‘insulated’ these Lead Acid batteries should have no trouble running a CRT Monitor. A real computer doesn’t need LCD and Lipos ;D
SX20 Pic 36 - 16 Jan 2019 - Lime Flavoured
The standard test of using a 20w car break light bulb to eliminate some green flavoured jelly.
SX20 Pic 37 - 17 Jan 2019 - Video Nasty
And other than the filthy screen.. we’m good. Lead Acids FTW!
SX20 Pic 38 - 18 Jan 2019 - Connectoring
So far much of this build has been bodge wired just to get things to work. The power PCB now has a mix of ‘real’ connectors and temporary tails (DC Jack)
SX20 Pic 39 - 18 Jan 2019 - Power PCB installed
Top down view.. That’ll do and those with a keen eye will see the SX20 JiffyDos Kernal. Noice!
SX20 Pic 40 - 18 Jan 2019 - Power PCB installed 2
It fits perfectly ;D
SX20 Pic 41 - 18 Jan 2019 - Helping, not helping 😀
Nice to find a pic of my old cat ‘helping’ (not helping) in my workshop/office. A bruiser of a rescue moggy that unfortunately didn’t get much older. RIP Spartapus 🙁
SX20 Pic 42 - 19 Jan 2019 - Back to the horror show
Who did this too you! Donor SX64 had it’s keyboard wires cut?!?!
SX20 Pic 43 - 19 Jan 2019 - And more bad things
.. have happened to the monitor controls
SX20 Pic 44 - 19 Jan 2019 - Moustache
Everybody had a moustache in the 80’s.. so why not your 1541?
SX20 Pic 45 - 2 Feb 2019 - Spectrum 128k to the rescue
For ‘reasons’ I happened to have a bit of speccy lying around.
SX20 Pic 46 - 2 Feb 2019 - Spectrum 128k who knew!
And it turns out, with a bit of minor fettling..
SX20 Pic 46 - 2 Feb 2019 - Spectrum 128k the perfect battery braket
.. makes a fantastic SX20 Lead Acid battery holder ;D
SX20 Pic 46 - 30 Dec 2019 - Time passes, battery last'es
RL takes over and it’s now the tail end of 2019. And the good news is, the SX20 still has all of it’s volts
SX20 Pic 47 - 30 Dec 2019 - It lives!
Filthy but working.. Just how I like it ;D
SX20 Pic 48 - 31 Dec 2019 - Old langs 74xx
And in the dying hours of 2019 I’m resurrecting the SX64 1541 controller PCB.. as you do
SX20 Pic 49 - 1 Jan 2020 - This is it
Did something happen in 2020? coz I’ve only got two SX20 pics and this is the better one.
SX20 Pic 50 - 28 Dec 2022 - Nothing but smeg in 3 years?
Maybe I’ve lost a bunch of pics, or maybe I didn’t touch the SX20 for nearly 3 years. Either way, it had gained fresh deposits.
SX20 Pic 51 - 28 Dec 2022 - That's better.
Looks like the 2nd donor SX64 had a better internal keyboard tail..
SX20 Pic 52 - 28 Dec 2022 - So rather than build my own
Finding this meant, rather than building my own custom cable.. Maybe a conversion will be possible. #Spoiler, it is ☺️
SX20 Pic 53 - 28 Dec 2022 - It's a tight fit
It’s a bit of a bugger getting all these tails on.. The pitch isn’t what we’d call ‘standard’ in 202x But it’s a done thing. Tick in the box!
SX20 Pic 54 - 28 Dec 2022 - And the other end
And best of all it works a treat.. So that’s the ‘keyboard’ done.. Next up.. feature creep!
SX20 Pic 55 - 28 Dec 2022 - This was not a good idea!
Oh noes.. If you want to point a finger on why the SX20 had such a slow birth, the PlusDeck 2 is probably one of the main culprits. That and 3d printing chassis parts to make it fit. But right now, I just put it in and thought.. good it doesn’t fit and anyways I’ve removed the tape interface and installed JiffyDos.. So no tape loading for you.. He said 😕
SX20 Pic 56 - 28 Dec 2022 - And a little bit more bodgery
I think at some point in the SX64’s past a joystick extension was hard soldered to the back of the I/O PCB.
SX20 Pic 57 - 30 Dec 2022 - Front panel thoughts
My thinking was this. SD2IEC + Power Buttons + Joystick Port
SX20 Pic 58 - 30 Dec 2022 - Backlit obvs
Early attempt at front panel PCB
SX20 Pic 59 - 31 Dec 2022 - One Million 3d Prints later..
I do love my 3d printers.. they may give you the option to prototype.. and you’ll end up with a nice thing.. Just don’t count the hours you spent waiting for the next minor revision charge to print.
SX20 Pic 60 - 31 Dec 2022 - And with all this messing about..
And with all this messing about..
SX20 Pic 61 - 31 Dec 2022 - Ultimately, it's something I never used
Feature creep eventually killed this layout.. but I think it would have been fine if I left it like this.