exxos's Atari, Amiga & retro forum

A1200 accelerator clock is now a happy bunny after being switched off for an hour over lunch:


OK, so just waiting on the caps for the A1200 PSU and the RAM for the A500.

Hey Jon, was just wondering what booster card you have in the A500?

I know I dont get on here much lately, but unless Im mistaken, I didnt see any mention of it earlier in the topic thread.

mrbombermillzy wrote: 30 Jan 2025 13:32 Hey Jon, was just wondering what booster card you have in the A500?

I know I dont get on here much lately, but unless Im mistaken, I didn't see any mention of it earlier in the topic thread.

I don't have a booster at present and I'm not sure I will get one. I kind of feel like while it's nice (I have one in the A1200 and in two of my STE's) but I don't know if what I'm planning to do with it will fit in with the need for a booster.

Of course that doesn't mean I won't :)

My mistake! :roll: I got mixed up with a post referencing your A1200.

But while Im here, there are lots of goodies available to the A500; depending on what you want to do, of course.

Did you have any specific plans for it?

Im a big fan of the colour boosting boxes (like DCTV,HAM-E,Colorburst) as they are pretty much unique to the Amiga, being that they use the additional RGBI outputs from the monitor sockets to encode compressed high colour images.

'Only the Amiga makes it possible', I guess, as the ST doesnt have the dual signal output on the monitor pins.

mrbombermillzy wrote: 30 Jan 2025 14:58 My mistake! :roll: I got mixed up with a post referencing your A1200.

But while Im here, there are lots of goodies available to the A500; depending on what you want to do, of course.

Did you have any specific plans for it?

Im a big fan of the colour boosting boxes (like DCTV,HAM-E,Colorburst) as they are pretty much unique to the Amiga, being that they use the additional RGBI outputs from the monitor sockets to encode compressed high colour images.

'Only the Amiga makes it possible', I guess, as the ST doesnt have the dual signal output on the monitor pins.

I have only had the A500 a few days so need to figure out what I want to do with it. I don't have any specific plans other than to use it like I did back in the day :) I guess we'll see.

And the A500 RAM expander is here:


As suspected the CR2032 is flat as a pancake so I'll pop in another, but aside from a few dust bunnies it's all good.

The connector on the A500 does seem to have a few green crusties on the pins, but I'll give it a quick clean and get testing :)

That's a pretty large board!
But good for it not to have any battery damage.

I'm a bit worried to hear about the green on the pins though... maybe it had an expansion card that had leaked before I got hold of it...it didn't have one fitted when it was added to my collection.

Sorry about that @rubber_jonnie

JezC wrote: 30 Jan 2025 18:18 That's a pretty large board!
But good for it not to have any battery damage.

I'm a bit worried to hear about the green on the pins though... maybe it had an expansion card that had leaked before I got hold of it...it didn't have one fitted when it was added to my collection.

Sorry about that @rubber_jonnie

No need to worry, I understand these things aren't perfect. TBH it seems to be entirely restricted to the pins, however it isn't seeing the extra RAM despite being super clean with no obvious corrosion. Everything on the pins cleaned up fine and that really is as far as any corrosion got. The RAM board does have a jumper on it but it seems to make no difference. All the ICs on the RAM board do have power but I haven't checked for anything like RAS or CAS on them yet.


I can't tell if the problem is the add in board or not though. There is space as @stephen_usher mentioned to add in another 512KB ram on board so I'm also looking at that and the 8MB/IDE board from Lotharek that was mentioned earlier.

I may desolder the pin header and drop it in the ultrasonic cleaner and make sure all the solder joints are good.

It does look like a Rev.6 so you should be able to add 512K of CHIP RAM.

In the meantime if you can get Amiga Test Kit on a floppy you can test the SLOW RAM expansion. I can't remember what the address range is though.

stephen_usher wrote: 30 Jan 2025 21:13 It does look like a Rev.6 so you should be able to add 512K of CHIP RAM.

In the meantime if you can get Amiga Test Kit on a floppy you can test the SLOW RAM expansion. I can't remember what the address range is though.

Yeah, I'm going to very likely do the onboard RAM expansion, looks like 4 RAM ICs, 4 decoupling caps and a couple of SIL resistors for pull ups, but I'll go and get the full SP from the interweb.

Good idea about Amiga Test Kit, I'll look into that too.