Nice, if only I had this video about 2 years ago. :) Interesting, I too used the Mean Well power supply. Yes, it's simpler using a 555 timer, instead of supplying 60hz signal with additional transformer & logic.
There was no need to drill through the label. Three standoffs would have been enough. You can attach a little block of rubber under the unsupported corner, for peace of mind.
Doesn't the C128 derive its TOD clock similarly to the C64, from the grid frequency? If so, a miniature transformer and half-wave rectifier would also do the trick. AFAIK the 64 doesn't need the clock for much and would mostly be fully DC operable with relatively minor mods, save for some expansions that may want to derive special voltages form the 9VAC. For another thing, I have been wondering if there is any way to track the vertical blanking of the VIC by hardware as an alternate source for a clock pulse.
What? You drill a hole in the case like you're a caveman from the stone age? You could have just 3d printed an adaptor fitting for the existing holes. This is totally irresponsible to destroy original Commodore hardware.
Plus one on the printed adapter. I also wonder what the failure of the original PSU was. As the B128 is pretty rare it might have made sense to send it off to someone with knowledge about SMPS.
You’re not wrong. I have prior experience doing a complete rebuild of the PSU in my CBM 256-80 (far more rare than a b128) when I replaced every component inside with new parts. That lasted me another couple years until it began to fail again, at which point I replaced it with a modern Mean Well also. Christian Forstreuter identified a design flaw in these power supplies which cause the issues. I think he documented it in his schematic.
Nice, if only I had this video about 2 years ago. :) Interesting, I too used the Mean Well power supply. Yes, it's simpler using a 555 timer, instead of supplying 60hz signal with additional transformer & logic.
29:25 💨
There was no need to drill through the label. Three standoffs would have been enough. You can attach a little block of rubber under the unsupported corner, for peace of mind.
Be that as it may, the hole cannot be un-drilled :)
Love your work! Was wondering if that clock gen board design was available? I'd like to get a few of those made up
Thanks!! Steve is going to make it available on his website, cbmsteve.ca/ once I confirm the 60Hz part.
Steve added info to his webpage: cbmsteve.ca/cbm2clock/index.html
You can also do this with a 1541.
Doesn't the C128 derive its TOD clock similarly to the C64, from the grid frequency? If so, a miniature transformer and half-wave rectifier would also do the trick. AFAIK the 64 doesn't need the clock for much and would mostly be fully DC operable with relatively minor mods, save for some expansions that may want to derive special voltages form the 9VAC. For another thing, I have been wondering if there is any way to track the vertical blanking of the VIC by hardware as an alternate source for a clock pulse.
So, true. Both the C128 & C64 utilizes the 9VAC for the clocks signal. However, the specifications for the B128 has this signal at 5V.
@@marcuswilliams3455 I was confuscated.
What? You drill a hole in the case like you're a caveman from the stone age? You could have just 3d printed an adaptor fitting for the existing holes. This is totally irresponsible to destroy original Commodore hardware.
Hahah! No doubt! I’m mostly glad the flames shooting out of the old PSU didn’t destroy it worse
Plus one on the printed adapter.
I also wonder what the failure of the original PSU was. As the B128 is pretty rare it might have made sense to send it off to someone with knowledge about SMPS.
You’re not wrong. I have prior experience doing a complete rebuild of the PSU in my CBM 256-80 (far more rare than a b128) when I replaced every component inside with new parts. That lasted me another couple years until it began to fail again, at which point I replaced it with a modern Mean Well also. Christian Forstreuter identified a design flaw in these power supplies which cause the issues. I think he documented it in his schematic.