INTRODUCTION
This is quite the departure from my other posts. And the reason for this lies squarely at the door of Covid. The pandemic and lockdown meant I wasn't getting out with my camera and as a consequence, my attention moved to projects I could undertake at home. This change of focus seemed quite natural to me - computers have been a part of my life since the 1980s and the urge to do something with that had always been there and the pandemic was the perfect opportunity to build on that. Literally.
When I decided to build a brand new Commodore 64, the first thing I did was hunt around the internet for any helpful guides to aid in the process. Whilst they may be out there, I didn’t manage to find a “one stop shop” of information. There are, however, a good number of separate resources which help.
My intention here is to pull together this information, as I understand it, to produce a simple resource for anyone who might wish to do the same or who simply has an interest in what it takes to build a 1980s 8-bit computer in the 2020s.
I will discuss the equipment required to undertake the build; the necessary parts that need to be obtained; where I bought them and total cost (correct at time of writing - I will include the actual price I paid – in the currency of supplier as well as a running total cost converted to EURO, GBP and USD using current conversion rates to give a broad idea of actual cost) as well as my honest thoughts and insights as the build progresses.
The first question to address is why? Why would I want to build a 40 year old computer now? The answer is simple: fun. I enjoy learning stuff in a practical way and I would get a real kick out of using a computer I had built myself.
DISCLAIMER
Everything was bought with my own money and I am not sponsored by any of the suppliers mentioned. I do not endorse any supplier mentioned here.
Where there is a % after a cost this means that I purchased more than one item from that supplier and the cost shown for shipping or tax is a percentage of the total cost of that particular purchase (e.g. if I bought two items from one supplier then the shipping cost shown against each item are 50% of total shipping cost).
BEFORE BUILDING
Before we start soldering anything, it’s important to understand what it is we’re actually going to construct and the limiting factors.
First we are limited by the parts we can obtain. We need:
- A case and accessories.
- A PCB.
- All the components for the PCB.
- A keyboard.
Let’s look at each of these in turn.
PART 1A. THE CASE
Whilst we might have a working bunch of electronics at the end of the day it’s neither practical, sensible or complete without a case and as I write this (in January 2022), there are presently only two options available which I would consider:
- A second hand, original case (Breadbin or C64C variant).
- A new C64C variant.
There are pros and cons to both but bear in mind the option you go for here, should dictate the next step which is the PCB you choose.
I wanted to use, at all stages, new parts where possible, but, contrary to what you may have heard or read it is NOT possible (at this time) to build a 100% new Commodore 64. However, it was my initial intention to keep salvaged parts to the absolute minimum.
With this stated, I will start the build by obtaining a brand new C64C style case:
Supplier: https://icomp.de/shop-icomp/de/shop.html
Cost of Case: €47.16 EUR
Additional Tax %: €8.96 EUR
Cost of Shipping %: €9.93 + €26.80 = €36.73 EUR
Total Cost of Item: €92.85 EUR
Running Total (in GBP, USD, EUR): £77.07, $105.85, €92.85
Personal Comments on Item.
Getting this case from the supplier in Germany to my home in Scotland was a costly exercise. There was a prohibitively high minimum order value to ship directly, caused by, the supplier says, new UK legislation following Brexit. In order to circumvent this I used the services of a German-based international shipping and forwarding company (myGermany) and thus incurred additional shipping expenses (which is why there are two values under costs of shipping - €9.93 from supplier to shipping company and €26.80 from shipping company to me). However, although very expensive and somewhat convoluted the process was swift taking only 8 days from ordering to taking delivery.
As regards quality of the product, I would describe it as fit-for-purpose. There are a number of quite noticeable and ugly marks on the case, this one in particular was prominent and quite disappointing, but it is merely cosmetic - not a crack:
However, in all fairness the supplier clearly states on their website:
“Due to the modern plastic, the choice of colours and the old molds, binding seams and sprues are visible for production reasons (see photos). This becomes most visible on darker colours. The desired variety of colours was more important to us and ultimately outweighed the perfection of the visual appearance. We would like to emphasize that the imperfections are not a sign of bad production quality, but of the genuine toolings that are now 35 years old. Detailed plastic flow analysis just wasn't invented in 1986!”
I will deal with, and disguise, this ugly mark later in the build. Also included are 8 screws to mount the PCB and two white rubber feet. I will be replacing both the screws and the feet. The screws seem poor quality and the feet… Well, I’m definitely not using white feet!
PART 1B. KEYBOARD MOUNTS
AND POWER LED
If I had been using a second hand Breadbin case, keyboard mounts would not be necessary. But we’re not. So it is. This is an essential element to our build and should be considered part and parcel of the case as it is used to screw mount our keyboard securely within. There are several options available here:
- Buy salvaged part
- 3D Print a new part
- Buy a new part
As the same supplier I purchased the case from also supplies keyboard mounts, I made life simpler for myself by purchasing these at the same time as the case. Costs shown below are calculated via % of total cost of order.
Supplier: https://icomp.de/shop-icomp/de/shop.html
Cost of Mounts: €14.42 EUR
Additional Tax %: €2.74 EUR
Cost of Shipping %: €3.03 + €8.20 = €11.23 EUR
Total Cost of Item: €28.36 EUR
Running Total (in GBP, USD, EUR): £100.6, $138.18, €121.21
Personal Comments on Item
These are very sturdy, excellent quality steel mounts which will easily outlive the computer, and me. They are a perfect fit in the selected case. Screws to mount the keyboard are supplied but strangely, rather than a more common Phillips head, these are hex screws requiring an Allen Key (also supplied) to fit which seems like one more thing to lose.
Power LED
Traditionally the Breadbin C64 had a red power LED. The C64C appears to have come with either green or red LEDs probably depending on the PCB that was used (my conjecture). For this build we are departing from tradition and going with my preference which is blue. Modern replacements in all hues are available from any number of suppliers but again my selection was simply a personal aesthetic decision.
Supplier: https://www.retroleum.co.uk/
Cost: £3.50 GBP
Additional Tax %: -
Cost of Shipping %: £0.27 GBP
Total Cost of Item: £3.77 GBP
Running Total (in GBP, USD, EUR): £104.37, $143.34, €125.73
PART 2 – THE PCB
The Commodore 64 was in production between 1982 and 1994 and during this time, both the case, and the PCB inside, underwent some fundamental changes. As intimated in Part 1, the case changed from the familiar and iconic breadbin design to the sleeker, but arguably less beloved C64C design, whilst inside the PCB also went through a number of iterations, driven, ultimately, to reduce costs by reducing the number of components.
In recent years, some of those PCBs have been recreated, with the specific intention of reviving broken machines and undertaking new builds. It’s not my intention to list every PCB variation Commodore produced for the C64, nor to list all of the new variants which are now available as there are many: from straight reconstructions of the originals to modern interpretations with added functionality. My thinking was to keep things as simple for myself as possible and of all the variants available I decided on the 250466 PCB design. This has the following benefits:
- It was originally designed for a C64C case
- It has a reduced chipset minimizing both cost and troubleshooting
- It’s a longboard so still has all the chips I’m familiar with
- It’s a popular board and as such there is some helpful information available
Supplier: https://www.tindie.com/products/bobsbits/sixtyclone-commodore-64-replica-pcbs/
Cost of PCB: $35.00 USD
Additional Tax: -
Cost of Shipping: $6.50 USD
Total Cost of Item: $41.50 USD
Running Total (in GBP, USD, EUR): £134.67, $184.84, €162.25
Personal Comments on Item
I would describe this “Sixty Clone” board as a work of art. With the black soldermask, white silkscreen and gold contacts it wouldn’t be out of place in a frame on the wall. It’s robust, chunky and the solder pads are a joy to work with, in my limited experience. The silkscreen is clearly marked for all components. The part of the PCB at the cartridge connector is too wide and some of my cartridges don't fit – the PCB will require filing down by a millimetre or so on each side. A surprising issue and one I'm not alone in encountering.
PART 3A – PCB COMPONENTS.
There are basically two ways to obtain the parts required to start this build – the hard way, and the easy way:
- The hard way is to track down each component individually.
- The easy way is to buy a pre-prepared kit.
For this build I initially took the easy way and this did not turn out well. I am not going to name the supplier (though there are a very limited number of companies that provide build kits of this type) and I have emailed to let them know of the problems I encountered and they have advised they will investigate stock from same batch which is fair enough. It is not my purpose here to bad mouth anyone, simply to relate my experience. Many others have had a positive experience and the company receives almost universal good reviews, so perhaps my experience was a one-off but I will speak about this later.
Supplier: not named
Cost of Pack: €82.45 EUR
Additional Tax: -
Cost of Shipping: €9.00 EUR
Paypal buyer security fee 5.4%: €5.12 EUR
Paypal Fee: €0.50 EUR
Transaction Costs: €0.50 EUR
Total Cost of Item: €97.57 EUR
Running Total (in GBP, USD, EUR): £215.65, $296.07, €259.82
Personal Comments on Item
The package itself should contain everything except the large ICs (Integrated Circuits) to complete the build, including all resistors, capacitors, filters, connectors and logic chips.
The pack I received was missing a 390 ohm resistor meaning I incurred an additional expense of £1.24 (pack of 20) to complete the set. Not a disaster and I didn't bother to complain to the supplier about this, but merely state this as fact. This brings our running totals to:
Running Total (in GBP, USD, EUR): £216.89, $297.77, €261.31
It is very difficult to say if this pack was value for money. What I can say with certainty is that buying this pack, from this supplier made the job of sourcing many disparate components ridiculously easy and (though I have not done the math) I suspect, after factoring in shipping costs of sourcing individual parts myself, buying the pack would be the most economic method. I am unsure as to the quality of the materials received not being overly familiar with them. The resistors in the pack were 5% tolerance and had I sourced these myself I would have sourced 1% tolerance. However, if we look at the parts list from the original service manual it states:
So what I’ve been supplied is exactly to spec.
There were a few inconsistencies worth mentioning with items received versus items listed in the BoM. The BoM specified 5% tolerance Inductors at L1 and L5, what was received were 10% tolerance; and the Timer IC LM556 specified was replaced with a NE556. None of this is problematic.
The round pin IC sockets I was supplied were an absolute disaster. Given what transpired later in the build I should have gone with my initial gut instincts which certainly had me questioning their quality simply based on their quite rough appearance, but having never compared a “quality” IC socket with a “standard” IC Socket I was ignorant of the consequences and I will pay for this ignorance later on.
PART 3B – MAIN ICs
To complete the PCB Build I still needed to obtain:
- 2 x CIA
- Basic, Character and Kernal ROMs
- 6510 Microprocessor
- VIC-II
- SID
- PLA
There is no lazy way to obtain these and each must be sourced individually. This is easy enough though and supplier, costs and additional info are itemised below:
CIA (COMPLEX INTERFACE ADAPTER)
There is no as-yet-available modern replacement for these and so they must be obtained from salvage. I am keeping my eye on the progress of both the XIA project by Jim Drew at cbmstuff.com, and the J-CIA project by Jani Laatikainen at 1nt3r.net/j-cia/. These projects looks like they will eventually produce a modern replacement for our CIAs but the ongoing chip shortage is delaying progress significantly.
Supplier: https://www.retroleum.co.uk/
Cost: £35.90 GBP
Additional Tax %: -
Cost of Shipping %: £2.79 GBP
Total Cost of Item: £38.69 GBP
Running Total (in GBP, USD, EUR): £255.58, $350.78, €307.74
ROMS (BASIC, CHARACTER AND KERNAL)
Modern replacements for these are plentiful. I merely chose these as I really like the aesthetic.
Supplier: https://diychris.com/index.php/shop/
Cost: $45.00 USD
Additional Tax: -
Cost of Shipping %: $18.59 USD
Total Cost of Items: $63.59 USD
Running Total (in GBP, USD, EUR): £302.00, $414.37, €363.7
6510 MICROPROCESSOR
Edit: since writing this, Jani's project mentioned below is now (Nov-2023) nearing completion and is stated as having no stability issues and passing all Lorenz test suite programs.
There is no as-yet-available modern replacement for these and so they must be obtained from salvage. There is an interesting project which allows you to use a 6502 microprocessor but for this build I don't want to simply replace one old chip for another. A project I definitely do have my eye on though is the J-CPU project, again by Jani Laatikainen, details of which can be found at 1nt3r.net/j-cpu/, but it looks like it will be 2023 or 2024 before anything transpires.
Supplier: https://ebay.co.uk/
Cost: £19.95 GBP
Additional Tax %: -
Cost of Shipping %: £2.36 GBP
Total Cost of Item: £22.31 GBP
Running Total (in GBP, USD, EUR): £324.31, $444.93, €390.47
VIC-II (VIDEO INTERFACE CHIP II)
Edit: At the time of writing, there was no as-yet-available modern replacement for the VIC-II so they had to be obtained from salvage. The VIC-II Kawari project was coming very close to being a viable replacement but had been delayed by the global chip shortage. The Kawari eventually became available in November 2022 and I have since installed one in my SixtyClone. Read about that here.
I believe the 250466 would normally have been populated with the 6569R5 variant but at the time of build I was unable to track down an R5. For now I have settled for the R3 variant.
Supplier: https://ebay.co.uk/
Cost: £24.95 GBP
Additional Tax %: -
Cost of Shipping %: £2.36 GBP
Total Cost of Item: £27.31 GBP
Running Total (in GBP, USD, EUR): £351.62, $482.35, €423.24
SID (SOUND INTERFACE DEVICE)
There are a plethora of modern replacements available for the SID. One of the most respected is the ARMSID which has received almost universal praise and also has the added benefit of coming with a software utility which can very easily change the behaviour of the chip to mimic either the 6581 or the 8580 variations of the original. This is very useful if playing demo’s or games which were written with a specific variation in mind.
Supplier: https://www.retrocomp.cz/eshop
Cost: €31.00 EUR
Additional Tax %: -
Cost of Shipping %: €8.90 EUR
Total Cost of Item: €39.90 EUR
Running Total (in GBP, USD, EUR): £382.25, $524.41, €460.14
PLA (PROGRAMMABLE LOGIC ARRAY)
The original variation of this chip has a very high and well documented failure rate. As a result, this is another chip which has a great many modern replacements available. Of these, one which has received a great deal of positive feedback is the PLAnkton which appears to have no compatibility issues at all. My only criticism: it’s on a green PCB and is going to stick out like a sore thumb on my board: I really would like to see these in black.
Supplier: https://www.retroleum.co.uk/
Cost: £12.50 GBP
Additional Tax %: -
Cost of Shipping %: £1.75 GBP
Total Cost of Item: £14.25 GBP
Running Total (in GBP, USD, EUR): £396.50, $543.94, €477.24
PART 3C – ADDITIONAL REPLACEMENTS
It was stated in PART 1A that, where possible, I want to use new parts rather than salvage. This is important to me as I don’t want the building of new machine, to mean sacrificing an old one. As it stands however, with the VIC-II, the CIA and the CPU there is simply no alternative currently available and salvage is the only recourse. There are currently projects on-going to produce modern alternatives for all of these but some appear to have stalled and given the global chip shortage currently being experienced, it’s not clear to me when these will see the light of day.
That said, there are a few more modern replacements I can throw at this build to ensure I am sticking with my original intent. These are:
- MOS 7701/8701 Replacement
- SRAM Memory Replacement
- 5v and 12v DC Switching Regulators
- RF Modulator Replacement (for Audio and Video Out)
I discuss these below but I do have more to say on this in a future post so stay tuned for my ramblings.
MOS 7701/8701 Replacement
The 7701 (NTSC) or 8701(PAL) is the chip which generates the dot and color clocks for the VIC-II. The original has a reasonably high failure rate which has driven demand for a modern replacement and there are many now available. The particular one I selected was chosen for no other reason than convenience (I was buying other items from that supplier) and aesthetics (let’s keep it to black shall we?). However, as you will discover later, this particular variant did not work properly.
Supplier: https://diychris.com/index.php/shop/
Cost: $17.95 USD
Additional Tax: -
Cost of Shipping %: $7.41 USD
Total Cost of Item: $25.36 USD
Running Total (in GBP, USD, EUR): £415.01, $569.30, €499.56
SRAM Memory Replacement
One of the most significant differences of the 250466 PCB to older variants is in the RAM. Where older PCBs utilised eight 8kByte RAM ICs, the board I have selected requires two 32kByte RAM ICs. And again, with time and age these chips fail. New old stock is still available and I am utilising these for the moment as my selected replacement (pictured) did not work. I initially selected a variant based on my “keep it black” aesthetic and no other reason, however come final construction it was clear this had fatal problems which I will discuss in future. However, for now my outlay was as follows:
Supplier: not named
Cost: $18.00 USD
Additional Tax: $4.30 USD
Cost of Shipping %: $3.50 USD
Total Cost of Item: $25.80 USD
Running Total (in GBP, USD, EUR): £433.85, $595.10, €522.26
5v and 12v DC Switching Regulators
This is perhaps the most controversial replacement being made in this build. The original parts 7805 and 7812 are no longer manufactured but can still be obtained as salvage or new old stock. Direct replacement parts are still available but after having undertaken some research and heard about modern replacements which do not generate anything like the same amount of heat my interest was piqued. I am not going to criticise the original parts – they are still in my original Breadbin and still working perfectly well after 38 years – there’s absolutely nothing to criticise! But for this build I’m in a position to try something new. The modern 5v Regulator (pictured) will not require a heatsink. For absolute clarity, the parts obtained were:
- Recom R7812-0.5
- Recom R-78B5.0-1.5
Supplier: https://uk.rs-online.com/web/
Cost: £15.06 GBP
Additional Tax %: £4.00 GBP
Cost of Shipping %: £4.95 GBP
Total Cost of Item: £24.01 GBP
Running Total (in GBP, USD, EUR): £457.86, $627.99, €551.08
RF Modulator Replacement
We need some way to get video out of the computer and the original Commodore 64 did this via an RF Modulator which processed the signals generated by the VIC-II and SID chips and modulated them, directing the signals to both the A/V out port and the RF out port.
The RF out port is all but redundant now – this took the signal from the computer and fed it into the aerial socket of your TV. You would tune your TV into the signal and this is how many people used their Commodore 64s in the 80s.
In 2022 I would never, ever use this method and only require use of the A/V socket which carries a composite signal and an early form of S-video signal. In the future we may not require this either but at the time of writing, the composite and S-video signals are all I require to ensure the build works and for initial testing. There are many and varied modern replacements for doing this but I have no need for anything complex at this time. Once again the basic RF Mod replacement I selected came down to simple aesthetics.
Personal Comments on Item
I have used this variant of RF Mod replacement before and I feel it important to point out that if you are using Composite out with these don’t expect a quality picture! In my experience they are worse than the original RF modulator and introduce heavy jail-bars. S-Video is much improved, but still a long way from perfect and jail bars are still a blight, especially with certain colored backgrounds - red for example is a horror show. Such are the tribulations of old tech. There is much talk of the "lumafix" which is supposed to further reduce jailbars but as this sits between the socket and the VIC chip i doubt there is enough clearance in the C64C case and honestly, I'm just not that bothered. It's good enough.
Supplier: https://www.ebay.co.uk/
Cost: $18.00 USD
Additional Tax %: $4.30 USD
Cost of Shipping %: $3.50 USD
Total Cost of Item: $25.80 USD
Running Total (in GBP, USD, EUR): £476.69, $653.79, €573.78
PART 3D – ADDITIONAL SUNDRY ITEMS
Finally, these items were purchased not because they were necessary to have a working machine but simply to “improve” the build:
- Replacement Screws for Case and PCB
- Heatsink and Thermal Adhesive
- Black Rubber Feet for case
- Bespoke Case Sticker
- Male and Female Pin Headers.
Very little needs to be said about the majority of this list. The screws are simply to replace the poor quality ones received with the case; the heatsink will be required by the VIC-II – it’s the only component left that will generate much heat and the black rubber feet are necessary because the white rubber feet supplied with the case would simply look ridiculous.
Total Cost including Shipping: £6.96
Running Total (in GBP, USD, EUR): £483.65, $663.33, €582.13
Of the two remaining items in that list, some more detail:
BESPOKE CASE STICKER
Supplier: https://www.stickersinternational.co.uk/
Cost: £16.00 GBP
Additional Tax %: £3.99 GBP
Cost of Shipping %: £3.95 GBP
Total Cost of Item: £23.94 GBP
Running Total (in GBP, USD, EUR): £507.59, $696.12, €610.86
The purpose of this is my attempt to disguise the nasty moulding marks on the case. This is a design I created myself but with fairly obvious influences! It is 66mm x 35mm on a brushed silver background. It achieves its intended purpose and I’m very happy with the look. Quite how durable it is remains to be seen but as the minimum order was four stickers, I have spares.
Male and Female Pin Headers
Supplier: https://www.amazon.co.uk/
Cost: £2.49 GBP
Additional Tax : £0.50 GBP
Cost of Shipping %: -
Total Cost of Item: £2.99 GBP
The sole purpose of these is to mount the RF Modulator Replacement and to make it easy to remove should other options come along in the future. With these I can simply lift it on and off with ease and they’re tight enough to hold securely in the meantime. At this price definitely not the best quality but easy to replace if this is a problem.
Running Total (in GBP, USD, EUR): £510.58, $700.22, €614.45
This concludes sourcing and purchase of all the PCB components, chips and miscellany.
PART 4 – KEYBOARD
The timing of my build is, perhaps, a little unfortunate. If I were to be writing this at the same time next year (2023) then my options may be a little wider but as things are right now, I have two sensible options as far as a keyboard is concerned:
- Mechboard64
- Salvaged original keyboard.
The Mechboard64 is a magnificent piece of work, utilising a bespoke PCB, a bespoke aluminium bracket, 3D printed key adapters, standard Gateron microswitches and (and this is the unfortunate bit) salvaged, original keycaps or 3D printed keycaps. This final point makes building a Mechboard64 pointless for me. I’ve not seen 3D printed keycaps of sufficient quality that I’d want to buy them and I would have to buy a keyboard, to obtain the keycaps, to build the Mechboard so… yeah, I’m buying a salvaged keyboard.
There are plans afoot for new keycaps as well as a completely new keyboard (Blingboard 64) to be manufactured at some point in the future but these are/will be crowdfunding campaigns and like all crowdfunding ventures, we cannot guarantee they will ever see the light of day. Indeed, reading the updates from Jim Drew on his keycap campaign over at Indigogo has been excruciating as problem after problem rears its head, however to be fair, Jim does appear to be handling every issue diligently and keycaps are finally getting out to backers. But given the scale of issues faced it seems likely this campaign will be a one off and once they're gone, they're gone. Future builders will be shit out-of-luck getting these new. And the Blingboard is years away from being produced, if ever. Thus, if I ever want to be able to use this machine, then a salvaged keyboard is my only sensible option at the moment.
Supplier: https://www.ami64.com/
Cost: £39.00 GBP
Additional Tax : -
Cost of Shipping %: -
Total Cost of Item: £39.00 GBP
This completes the sourcing and purchase of all initial components. Of course additional costs will be incurred as upgrades and chip replacements become available.
TOTAL COST OF PARTS
Grand Total (in GBP, USD, EUR): £549.58, $753.65, €661.25
of which £101.93 ($139.83, €122.74) was simply on shipping.
In Phase 2, I start the build and encounter some show stopping issues.
