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Vicky Twenty - building a Vic-20 from (mostly) new parts. So it begins.

W

ith the successful sixtyclone under my belt, I was delighted that Rob Taylor decided to work his magic with the Vic-20. The Vic is very close to my heart; not my first computer but the one I spent years with. My board arrived on 25 Feb and it's absolutely beautiful.

At first I thought this project would involve more 'pulls' than the sixtyclone, because there are fewer modern replacements for the key components. However, I was delighted to find that not only is a 6502 manufactured today, but the same goes for the 6522s. So that's three out of the four most important chips available as freshly-manufactured parts. Real chips too - not modern boards with header pins to fit the original footprint.  Here's my 65C02 in its engagement ring box! 
It's the same chip that I have in my Mini Pet. It's an improvement on the 6502, adding a few new instructions, so I'm really chuffed about that.

The fourth of the 'big four' chips is the VIC itself. Once again, I was delighted to find that it's easy to buy 'new old stock' VICs. The 6561-101 is the last revision (6561 is the PAL version). 1987 seems very late - am I reading that date code correctly?   
It is allegedly brand new and unused and that appears to be true.  The 'bits' on the surface are from my acetone-soaked cotton bud (it passed). We can only wait and see whether it works. 

Rob bas made a BOM available as a spreadsheet that you can upload to Mouser and populate your shopping cart. (As you can see in the picture, they don't seem to mind packing small components individually for you!)  This was a real time saver. With my sixtyclone I had looked forward to searching for the right parts with the right footprint but to be honest I didn't enjoy that part at all. 

Bob's list doesn't seem to include all components. I simply ordered what was on the list.  There were some items out of stock too. When I've put what I have onto the board I'll see what I still need.  
So here's where we are today. I still have loads of components to put on the board but I've made a start. The resistors (that lie flat) are in place, as are all IC sockets. 

Where we go from here  

Some small components still to buy, because they weren't on the BOM or because they were OOS when I ordered. Same goes for the logic chips and RAM. Many hardware items (DIN sockets, cartridge port) weren't on the list but I guess can be sourced. Other hardware items such as the cartridge cover and the metal box around the VIC obviously aren't available today. I'm not sure whether to simply leave those off, or harvest them from a dead Vic20.

I'm thinking about the case. I have some Vic20s, one isn't working, so I could take case, keyboard and maybe some components from that without feeling too guilty.  One plan I like is to take my mankiest case and spray it pale pink (Rob calls this clone the 'Vicky Twenty'). Or maybe attempt retrobrighting / spraying to something like original colour.  Another option is to design a clear plastic enclosure like the one I have for my Mini PET. 




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