Hi, i got one A500 with extra memory. It says A501. when i opne the trap door, it has a metal cover, i cannot see it, i would have to remove all the metal stuff to access to the memory, it still has the original Commodore seal. I didn't remember to see A500 with 1 MB ram inside metal shell like this. It's not a 500+, it's an old A500. Did they release a lot of them like this?
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Yes, the official Commodore trapdoor ram expansions were encased in metal shielding. It will be a standard 512KB fast ram expansion for the A500, giving the A500 a total of 1MB.

The A501 was A500 specific and should have a RTC battery backed clock included. Whereas the A501+ ram expansion was for the A500+ and didn't as the A500+ already has a clock built in.

It would be worth you removing it and opening it up as the clock battery is the type that can leak and cause damage, so it is worth checking this and removing the battery with some wire snips if it is leaking.
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ok, must check it, but look like the metal shielding is coneected to the major sheild, didnt look to be indipendent. I dont know now if i can remove just the shiled from the expantion or i need to remove all the shield. but, my other Miggys dont have any shiled at all...
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I open it Today:


tha A501:


How do i open this case? I do not have experience with soldering to remove that clip, i am thinking in cuting with a cut pliers...
will i damage anything, doen't look to have any circuit near that clip...

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Oh, I'm not sure. My A600's A601 ram expansion just has some clips to unbend to open it. Not seen one exactly like that. Are the top and bottom of the shielding separate? If so could you just bend the top up and not need to desolder the joint? I'm wondering if that is like that to ground the ram card to the shielding...

BTW, the motherboard of the A500 itself looks in great condition. Nice purchase.
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I does not open if i not remove the solder in that pin... i think it does not have any think that could be broken in that area.
I will try tho cut it gently
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I open it today,
it looks like it has a bit of leak ...... help please !!! What should i do?
i found a real bug inside.... did a nice macro of it:

images of A501 with leak(?) and the real bug i found (it is in the last photos)
http://lobodias.com/html/a501_ram_expansion.html
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As the battery is leaking, you need to remove it as the acid can eat into the pcb. If you don't have a soldering iron just use some wire cutters to remove it. The memory will still work fine, just without the rtc. If there is any acid on the pcb you need to clean this with some cotton buds and alcohol or vinager. You can replace the battery with a coin battery and diode if interested.
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Ok,
some cotton buds and alcohol or vinager..... witch is better?
the coin battery, what is the specs for it? can you tell me where i can buy them? and the diode?
how to assemble them?
I guess the battery is connected to the pcb in 2 points... so should be a + and a - the coin is the same has a + and -, but what about the diode? must i place it where? before the +? the - ?
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