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Re: Sporniket's log on hardware stuff
Posted: 23 Jul 2022 12:55
by Cyprian
@sporniket are you going to recreate 260ST motherboard?
Re: Sporniket's log on hardware stuff
Posted: 23 Jul 2022 13:30
by sporniket
@Cyprian that's the plan.
edit: the sheet mention it is 260 and 520 ST.
edit 2 : just to be clear, I plan to have complete schematics and pcb, but I don't plan to build.
Re: Sporniket's log on hardware stuff
Posted: 24 Jul 2022 07:33
by sporniket
Placing and routing done. Some route are provisionnals as the vias are in fact the legs of the shifter...
The
github repository is up to date.
Next session will happen around end of july/begining of august, as I am trying again to manage several projects simultaneously.
Capture d’écran du 2022-07-24 08-09-09-32c.png
Capture d’écran du 2022-07-24 08-12-54.jpg
Re: Sporniket's log on hardware stuff
Posted: 30 Jul 2022 07:32
by sporniket
The shifter, composite with or without modulator, and the video port... I almost overlooked that the modulator get red/green/blue directly from the transistors directly, and not after the resistors like the video port.
subsheet_102-U31-Shifter ; J6-Video port.png
Re: Sporniket's log on hardware stuff
Posted: 08 Sep 2022 07:53
by sporniket
Going on a little bit. The previous sheet was not complete, with missing numbering and one description missing.
I also reworked the layout in order to visually link Q3~Q5 to their regulated power rail instead of using a label.
subsheet_102-U31-Shifter ; J6-Video port.png
Now working on this part of the PCB...
edit: github is up to date
Re: Sporniket's log on hardware stuff
Posted: 08 Sep 2022 09:06
by rubber_jonnie
nice work @sporniket, your STE schematics were a lifesaver when I was fixing @BrettRogersUK machine, I'm confident that these will be just as awesome :)
Re: Sporniket's log on hardware stuff
Posted: 08 Sep 2022 09:36
by sporniket
rubber_jonnie wrote: 08 Sep 2022 09:06
nice work @sporniket, your STE schematics were a lifesaver when I was fixing @BrettRogersUK machine, I'm confident that these will be just as awesome :)
Thanks, and I hope so too. At the very least, the schematics will not be mixed with the 1040ST : in the scanned document I found (a field/service manual) there was a bunch of half pages mixed together that looked like left part then right parts, but in fact when printing each page, I then played a game of "which side goes with which ?). And no more deciphering of handwritten notes. The epitome of satisfaction would be that the PCB reconstitution "just works", but it's very unlikely that I order one and do the build.
Re: Sporniket's log on hardware stuff
Posted: 08 Sep 2022 10:25
by rubber_jonnie
sporniket wrote: 08 Sep 2022 09:36
rubber_jonnie wrote: 08 Sep 2022 09:06
nice work @sporniket, your STE schematics were a lifesaver when I was fixing @BrettRogersUK machine, I'm confident that these will be just as awesome :)
Thanks, and I hope so too. At the very least, the schematics will not be mixed with the 1040ST : in the scanned document I found (a field/service manual) there was a bunch of half pages mixed together that looked like left part then right parts, but in fact when printing each page, I then played a game of "which side goes with which ?). And no more deciphering of handwritten notes. The epitome of satisfaction would be that the PCB reconstitution "just works", but it's very unlikely that I order one and do the build.
Yes, I can completely understand that, I've had a few machines (Dragon 32, 600XL, others too) which have all had multi part or left/right side schematics, it's a bloody nightmare tying stuff together.
I usually end up printing the pieces out and joining them together, but the Dragon was particularly frustrating, as there were 3 parts, 2 differing schematics and a separate one for the PSU!
Also, they were jpegs and not the best quality.
Re: Sporniket's log on hardware stuff
Posted: 22 Sep 2022 08:14
by sporniket
After adjusting the PCB size and the positions of the holes (see
viewtopic.php?f=23&t=5773 ), I finished to place the components around the shifter.
I had a hard time to find :
- the location of R127 as the pictures of motheboards I use as help are contradictory I used the scanned pcb from the service manual to decide
- the location of the group around Q10, that appears nowhere on the pictures. Again, I found some traces that are matching beside the video port.
atari-520ST-wip.jpg
Now it's time to do some routing
Re: Sporniket's log on hardware stuff
Posted: 23 Sep 2022 19:50
by sporniket
Enough routing for today. Next month I will do the EPROMS.
Capture d’écran du 2022-09-23 20-35-38.png
Some eye candies...
Capture d’écran du 2022-09-23 20-37-44.jpg
Capture d’écran du 2022-09-23 20-39-35.jpg
As usual, the github repository is up to date.