Commodore Amiga A500 Repairs Part 9 (My A500, A500+ and RAM Expansion Problems)
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- Опубликовано: 10 фев 2025
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Another A500 / A500+ video in the never ending series...
Part 1 - • Commodore Amiga A500 R...
Part 2 - • Commodore Amiga A500 R...
Part 3 - • Commodore Amiga A500 R...
Part 4 - • Commodore Amiga A500 R...
Part 5 - • Commodore Amiga A500 R...
Part 6 - • Commodore Amiga A500 R...
Part 7 - • Commodore Amiga A500 R...
Part 8 - • Commodore Amiga A500 R...
#commodore #amiga #repair
Great video, I lost track how many A500 & RAM boards where faulty you have so many😉 will there be a part 10... please!
Gadget never give up saving consoles & retro computers, plus your eye for details too, your channel is the best thing on RUclips!!!
Retrobright I don't do anything just dump the cases etc in the sun, takes time but works a treat!!!
Thanks mate =D Yes, there will be a part 10,11,12,13 probably lol - bits waiting here for me to look at!
Another excellent vlog! Top tips for pcbexplorer: click all the traces you want to test, they get different colors, so you don't have to hover your mouse. Also go to settings (top right) and change the pcb color to 'proto', which is a kind of brown. It contrasts better with the colors the traces you're interested in are given. Rev 3 and rev 5 boards have the power led that goes off if the filter is turned off instead of go dim, like rev 6A and 8A boards. The amiga systest floppy alignment test is REALLY useful, you can usually align the lower head by loosening the stepper motor screws and turning it, until it reads 11/11 sectors on all tracks on a reference disk, and the upper head by loosening it's screws and doing the same :-) The A2000B mobo uses only 470uF caps for the video hybrid DAC Vcc, and still looks ok video wise. I'm not sure the 3300uF ones really improve things or it was a legitimate cost reduction..
Thanks =D I will experiment with that FDD test stuff when I get time!
@@GadgetUK164 you changed the cap for video hybrid for a 3300uf, was there any gain in the end ?
Great job as usual Chris. And yeah, empirically, the caps have to be changed even on A500. Those tend to dry more than they leak (once changed, the display regains its crispy clear aspect). This is what i noticed when i changed them on my A500.
Quelli smd dell'A1200 sono molto peggio
Hi Chris. I’d also change any (electrolytic) cap near a custom component, such as an ASIC (Agnus, Denise, Paula, etc…), that hybrid module, a PAL/GAL, custom-programmed microcontroller, or any chip that’s super expensive (or impossible) to source or (re)program. 😋
I keep thinking why noone use some kind of sealant after retrobrighting. Just lool at any old yellowed device that has had stickers on them... No yellowing on the plastic underneath the sticker. So in my mind dpraying it with some sealant would stop it from turning yellow again... ?
Great vid as usual. Same on the retrobrite.
Thank you for the great vid, just transplanted my 500+ to an a500++ few small probs, but up and running now, have 8mb fast ram, 1mb chip onboard, but would love 1mb slow ram on top, have 2gb hdd for work bench and 3 4gb for something lol, keep up the great work 👍
Have you considered building up an A500++ board? It was a total save for my A500+. I didnt save my Gary chip but saved everything else more or less.
Yes I have, but it's a lot of work and quite honestly I prefer to repair than build stuff!
Love your video's, very helpful. Do you have a video that shows all possible issues and fixes with A500 R5 not booting
Thanks! There are litterally way too many possibilities for one video! For example, one broken trace around one of the main chips would cause it to not boot. Common issues are CIAs, RAM, Fat Agnus Socket, Fat Agnus, Gary Socket or Paula Socket. It's rare for Gary or Paula to die from my experience, Agnus does though. RAM, CIAs or bad single wipe sockets are most of the problems with R5 boards.
Put the 500 out in the sun for an hour or 2 and the whiteness will disappear. I've recently discovered this.... also works with marbling on STs for example :)
What webservice do you use there at around 33min in? The one were you trace the board.
Amiga PCB Explorer
Ho visto tutta la serie dei 9 video,lavori abbastanza bene
Thanks =D
Yes but I thought the code would be looking for copy protection that has been circumvented. had the game copy protection to begin with?
I am not sure where you mean in the video?
It's difficult to tell in the video but is the Agnus seated properly? It looks a bit lifted on one side but hey it does seem to be working. ;)
Yes, it's in there properly =D
Do not put any grease on the rod of the floppy disk drive. The rod has a sintered bearing and dirt can now adhere and make the read head stiff.
Thanks, if it were new or had low usage, I would agree - but it's 30+ years old! Very likely any lubrication in that sintered bearing has run low.
Great video, thanks for posting!
my copy of bubble bobble never worked on anything except kickstart v1.3
RE: Cylinder. Yeah, it's a cylinder as it's the track on both sides of the disk. Or even better imagine that disk had several platters. The same track on each platter would look like a cylinder if you visualised them all on their own.
What about a add in board that would take 4x DDR4 RAM modules and see if that solves the problem.
You cannot just add DDR4 RAM to an old system like this! The problem was missing traces on the two different A500+ boards.
Hi Gadget any chance I can pay you to re cap my working a1200?
I cannot offer customer repairs sorry!
Nice work.
Thanks!
Just for reference..... The NTSC Fat Agnus is the number 8370, PAL Fat Agnus is 8371 and 8372A is the FATTER Agnus. Fat Agnus accesses 512K chip ram, and Fatter Agnus accesses 512K or 1MB Chip ram. At least here in the states, later sold versions of A500/2000s were sold with Fatter Agnus(8372A) installed but not enabled for 1MB Chip ram.
Where’s my fire? Where’s my Terrible Fire? Ha, just kidding. 🤣😂😆
Buy the mini ,
It looks nice, but no functioning keyboard - I would prefer a real Amiga I think! Good for people that just want to play a few games without the hastle though!
Sono d'accordo
@@GadgetUK164 i loved my amiga , I wish that I had done more with it other than play games , I had the hard drive with a 4gb hard drive i think it was .
@@GadgetUK164 pretty sure I have an amiga 500 and 1200 with original commodore grey monitor, external floppy drive and stacks of pirated games in my mum's atitic from when I was a kid. Only problem is I know literally nothing about electronics so would likely be just a hair pulling exorcise trying to get it all up and running again. Lol hopefully they make a maxi version of the new amiga thing and I'll just roll with that. (actually I think it was a 600 not a 500)