flemingt

DRAMS came in the post today and the U1MB, AV cable etc are due Thursday. Weekend project sorted! Some questions about the AV port on the PAL 600xl. Is it monochrome with mono audio? Are there any mods required to make best use of that port?

That would be great! I'm using freeCAD but I'm sure I can figure something out. If not I can chop up the stl on thingiverse.

looking really nice @mdivancic! Once my board arrives I can do some measuring up and see if I can knock something up for the 600xl.

Looking good. Conceptually very similar. I took a simpler approach to mine, partially due to CAD skills, but also to minimise support structure requirements. Eager to see how this turns out.

yes, U1MB ordered, along with a proper AV cable. Also, some cheap and cheerful ram chips from ebay to get it up to 64kb too. I will try, a lot to learn (and re-learn!). hopefully you have better luck on your next retro-brightening attempt.

that's great @mdivancic - I'm more than happy to share ideas and designs. Do you have any dimensions of the board? thickness, overall dimensions, hole spacings? I can start sketching something up. I have an idea that should be printable with no supports. edit: something like this, but once I measure or get dimensions for the U1MB I'll refine further.

Thanks, really happy with it. I even managed to keep the stickers on the underside of the cases intact. Though the aluminium model badges could do with some love. That bodge was done before I got the system (which I'm guessing was 1988?), so I assume it's factory or my uncles attempt to improve the display output as it's attached to the RF modulator. I'm sure more knowledgeable people on here can let us know. I've a bunch of parts coming from from the UK and Poland to upgrade the internals and finish it off. Really sorry to hear about that mishap!

ordered a bunch of stuff from lotharek.pl, now I wait...😀

yeah, you're right. I was being lazy. I ordered a pair from ebay out of the UK so they should be here in a week or so.

thanks @flashjazzcat OK, time to put my money where my mouth is... since I'll be after the U1MB anyway, instead of the 64kb upgrade per above, would it make more sense to use this: https://lotharek.pl/productdetail.php?id=291 so I can get them both at the same time and possible save on some shipping costs? while I'm at it I can pick up the AV cable and an SIO loader from the same store... thus spending more time and money on the system than it's probably worth 😅

Brill, though for the time and effort I think I found one on ebay. I'll see what the seller comes back with regarding compatibility. Good video series! Wow, notching the board, brave! It also looks like I'd need a finer tip soldering iron for that via work, but that's something new to try. I presume the RF shield doesn't fit after that. I'd probably just knock up a 3D printed adaptor and hook it over the mainboard. I have some ideas, based on some raspberrypi cases I've been printing. would something like this work for the 64kb upgrade? https://www.ebay.co.uk/itm/5PCS-Dynamic-RAM-IC-NEC-DIP-18-UPD41464C-10-D41464C-10-UPD41464C-D41464C/162784727849?hash=item25e6b9d329:g:VhYAAOSwovNaIkQx

I've been documenting my restoration of a 600xl on my twitter here: One of the first steps was retro-brighting using Neil from The Retro Mancave technique. It was my first time doing any sort of retro-brighting, and I'm really happy with the result.

thanks, PAL - Ireland. that thread link has lead me to here: https://lotharek.pl/productdetail.php?id=198 for an AV cable and I could remove the RF modulator. https://lotharek.pl/productdetail.php?id=291 for a 64kb upgrade https://lotharek.pl/productdetail.php?id=56 for a subsequent upgrade. Looks like it would be a tight fit. although this looks interesting too due to space constraints in the 600 chassis: http://www.van-radecke.de/SRAM/576KB_SRAM_600XL.pdf Has anyone experience with these?

Per earlier post I've checked that the keyboard presses come through for several of the keys. I've just finished continuity checking through the connector and from the connector back to the the nearest solder point / component / pass through. All good I did notice a factory (I presume) bodge over by the RF modulator. Just noting this for interest. Working under the assumption that the mylar trim back or replacing the 4051s will fix this aspect. I think it's time to consider upgrades before reassembling in the case and plugging the keyboard back in. I know that memory is a weak spot in this system. I also need to get a proper AV cable as opposed to using the antenna port. Any recommendations on where to source these items?

Snip snip

It's actually completely transparent, the black is the background! The traces have worn through.

Sure, transparent mylar membrane plugs straight into the pcb. Also, the worn leading edge.

I've been able to check several of the keys, using the very helpful diagram and a level of dexterity trying to do 3 things at once and they seem fine. However the contacts at the edge of the mylar look worn through. I presume it's ok to trim about 2.5 mm off?

Thanks for the input. It was my first time doing any kind of retro-brighting and the case was in a sorry state, so I had noting to lose. Over-the-counter hydrogen peroxide is restricted and/or expensive over here (IE) so I went with what was available. I just copied Neil from Retro Mancave. https://twitter.com/TheRetroManCave https://www.youtube.com/channel/UCLEoyoOKZK0idGqSc6Pi23w He is doing a series on the 800xl which inspired me to dig my 600 out. I massaged, topped up, and realigned with the sun every 20 mins, I'm really happy with the results! Do the silver keys (and break) run through those chips too? Now to break out the multimeter!

Thanks for all the great info. Definitely some probing to be done with the multimeter. I don't have the big DIN av cable, just the antenna one. I'll see if I can find a pinout and wire a speaker across it. I'd a cursory look at the solder joints and pins on the connector and they seemed ok, but I will test them too. I don't have a resistor board, the keyboard plugs straight into the logic board socket, maybe it's a version thing? The power led makes contact with the mylar just below the help key. It lights up when the system is switched on.

Thanks, I'll check continuity tomorrow. Given that the sound isn't working either I suspect that it's something more.

Hi everyone, I'm a complete n00b and I'm looking for some advice. I've dusted off my old 600xl which was a hand-me-down from my uncle back in the late 80s and decided that it would be a great project to get it back working again. Upgrade it and show it to my uncle, who's now in his 60s. its a stock 600xl, PAL region, membrane (mylar I think) keyboard. I've created a twitter thread here documenting my progress to date: So far I've given things a general clean and retro-brightened the case and that of the 1010 cassette deck. I've checked the PSUs, 600xl is fine but the tape drive doesn't work. I've sourced one that will do the tape drive from my parts bin. Everything went back together fine, hooked it up to the TV, turned it on and very surprisingly got the "ready" prompt. Unfortunately the keyboard isn't working with the exception of reset, option, select, start, and break. Thinking it was membrane oxidation, I stripped the keyboard back down and used a magic sponge to clean all the traces. I was surprised at how well that worked! I also swapped around the 2x 4051 chips and reseated C012294-19 (POKEY, I think) to see if that would make a difference. Unfortunately not, same as before only the silver buttons & break work. Those keys were enough to get into the diagnostics; memory checked out ok but no sound over the antenna cable. So I'm looking for a bit of guidance on where to go next. Pokey dead? I can imagine they're hard to come by these days. Some googling lead me to something called POKEYMAX. Keeping in mind that I'd like to upgrade the memory too, what options do I have? Advice and guidance welcomed! Thanks T