Denial

I just noticed the Sixty Clone guy is listing the “Vicky Twenty” on Tindie. Not sure if he’s part of this forum or this has been posted already. I used the forum search and couldn’t determine if anyone else has posted this.

Great news though. Just need a VIC replacement now!

Have you got a link?

https://www.tindie.com/products/bobsbit ... b-replica/

I would have posted it first up, but didn’t want to seem like I was pushing a product.

The Sixty Clone boards are looking popular, hopefully these are built on whatever lessons were learned from that development cycle.

Very interesting, I didn't even imagine that replica boards were produced also for the VIC-20.
US based I guess though...

orion70 wrote: ↑Fri Feb 19, 2021 10:10 am Very interesting, I didn't even imagine that replica boards were produced also for the VIC-20.
US based I guess though...

Nope, UK by the looks.

This replica board is a great job, and probability its value is also because it's like as the original one....

Personally I would have implemented some tricks ....
1 ) the double mounting possibilities to be fitted ROMs as 2332/2364 or the 27C32/27C64
2 ) using 2x 8kram instead 2x2k+3x(1/2)k
3 ) using an xtal oscillator and not a resonant quartz that has to be tuned with special tools and a good frequency meter
4 ) using the power switch not for the power but for closing a mosfet that switch on the power (no power current on mechanical switch)
5 ) ESD protection on each line that could be connected with the external world
6 ) powering it with a 12Vcc (or with the 9Vac from original plug) with a 5V DC-DC converter inside
7 ) A better analog circuit for improving video quality
8 ) the extra tracks on CPU to be also fitted by 6502C "Sally" and W65C02S
9 ) extra "diodes" on 6522's /IRQ (and keyboard matrix) lines for permit the use of 65C02s and W65C22S

I'm bewildered why it has footprints for the original ROMs, they're one of the things that fail. Everything else (except the VIC itself) is easy to source.

I’m contemplating getting a board and the optioned components.

I’ve been looking, with no leads on a VIC repro, but I’m not completely in touch with the Vic 20 scene. Also waiting for the miracle of new breadbin cases.....

What components other than the VIC 6560 is needed for the NTSC configuration? I assume the crystal. Will this PCB work?

I was also thinking getting Run-Stop Restore's Vic part kit https://retro8bitshop.com/product/parts ... ore-vic20/ but I see they only have the pal Vic.

GaryM wrote: ↑Tue Oct 12, 2021 5:12 pm What components other than the VIC 6560 is needed for the NTSC configuration? I assume the crystal. Will this PCB work?

Yes, you will need to replace the crystal, and, also, the Kernal ROM. Here is an example of a Vicky Twenty with that PAL->NTSC conversion, so, yes, PCB seems to work ok in both modes:

https://youtu.be/0SmYOWz4hB4

Hi, I was wondering what diodes are used for the 65c22N, both for the keyboard and the interrupt pin. I get a lot of characters on the screen without touching the keyboard when I use my 65c22N. The NMI seems to lock up the computer when I try to load a program from the 1541.

Thanks everyone.
Happy New Year.

I've built a Vicky Twenty, and it is rock solid, zero problems with random characters showing up, and I've not observed any NMI problems. I built mine as a PAL version (I'm in the US and needed a PAL system, and this seemed to be the cheapest and most enjoyable way of getting one). I'm using 65C22s, so that's probably not your problem.

I guess I'd start looking for bad or missing solder joints, pins shorted together, that sort of thing. I use magnifying glasses for this and take my time.