Amiga 500 trapdoor 0.5/1.0/1.5/2.0 MB memory board (DIY A501)

[PeteAU]

Hi Amibay,

I have some A500 trapdoor circuit boards for sale. They require some DIY soldering to complete, but are reasonably easy for 512 KB, but more difficult if you want more RAM.

In summary, what you can do with this board is:
* 512K for A500, this can be CHIP or SLOW depending on Agnus.
* Real time clock with coin cell battery.
* 2MB for A500 with gary adapter, adds 0.5chip + 1.5slow, machine total becomes 2.5MB.
* 1MB additional chip RAM for A500+.

The bare minimum to get this working are these parts:
1. The board.
2. A 2x28 right-angle 2.54mm female header (or get a 2x40 and cut it).
3. One or two 0805 100nF capacitors (I can include them, just ask).
4. One SOJ42 memory chip. Pull them off old 1990's SIMMs or search for "SOJ42" on AliExpress.

There is a further development thread on EAB, which you could search for.

Price: AUD$15 per board (this is around €10,70 euro) by Paypal 'friends & family' payment. Postage is at your risk, unless you want to pay for tracking.

Australia Postage:
AUD$1.00 for small letter - 1 board only (one stamp).
AUD$2.40 for "large letter post" (two stamps) + small cardboard 20mm box.
Add 50c for a priority label.
AUD$7.60 for a parcel - probably over-kill, but it's your option.

International Postage:
AUD$2.95 for letter post (in an envelope, taped to a postcard, one board only).
AUD$8.00 for large letter (in a bubble bag).
If you prefer a parcel, let me know, but it's a lot more expensive.

PM with your country and I'll give you details. If you send me an extra $1 I'll include the capacitors (tell me how many you want).

[Cmaxwellau]

Hi mate,

* 2MB for A500 with gary adapter, adds 0.5chip + 1.5slow, machine total becomes 2.5MB.
* 1MB additional chip RAM for A500+.
I'm interested in these. I'm in VIC

[PeteAU]

Hi mate,

* 2MB for A500 with gary adapter, adds 0.5chip + 1.5slow, machine total becomes 2.5MB.
* 1MB additional chip RAM for A500+.
I'm interested in these. I'm in VIC

PM sent with Paypal details. I assume you want two boards? They are all identical, you just set different jumpers or put different amounts of DRAM chips on them. I suggest you go for the $2.40 post for two.

[EzdineG]

Interested, pending shipping to the United States. Looking to add to a rev 5 A500 w/IDE68k.


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[sebmacfly]

Interested, pending shipping to France, sending PM.

[PeteAU]

Payment received & boards sent to EzdineG, Rupture.

Shipping cost is the same for any country ($2.95 or $8.00, please see first post.

P.S. I have a variant of the board that takes SOJ40 memory instead, if you prefer that.

[DesktopDynamite]

Interested..pm follows with questions..

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[sebmacfly]

Interest withdrawn, don't have the right tool to solder DRAM chips. Thanks

[Rupture]

Thanks PeteAU. I Got my boards today.

[PeteAU]

If you can't solder, I have complete & finished boards in another thread (search it). They are a miniaturised 1MB version.
But it's fun to DIY.