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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Dr. Chef on August 08, 2014, 03:07:07 AM

Title: A501 RAM expansion not working?
Post by: Dr. Chef on August 08, 2014, 03:07:07 AM
I thought I only had 512k of ram, but opening up the trapdoor, I found out that it had a A501 ram expansion. When I boot up the Amiga it shows the time (probably a dead clock, since it shows 1970's) while loading, but when I remove the ram expansion, it shows no time, but once I'm on the Workbench (1.3) it shows 371752 bites of free memory, or If I remove the card, it shows the same amount. Is it dead Jim? Should I buy another card, or is there a way to get the Amiga to recognize the card fully?
Title: Re: A501 RAM expansion not working?
Post by: sm3 on August 08, 2014, 04:21:37 AM
Quote from: Dr. Chef;770572
I thought I only had 512k of ram, but opening up the trapdoor, I found out that it had a A501 ram expansion. When I boot up the Amiga it shows the time (probably a dead clock, since it shows 1970's) while loading, but when I remove the ram expansion, it shows no time, but once I'm on the Workbench (1.3) it shows 371752 bites of free memory, or If I remove the card, it shows the same amount. Is it dead Jim? Should I buy another card, or is there a way to get the Amiga to recognize the card fully?

 Check to see if there a switch on it. Most of trap door expansions have a switch to turn on/off the RAM expansion.
Title: Re: A501 RAM expansion not working?
Post by: Jiffy on August 08, 2014, 11:07:09 AM
The A501 doesn't have a switch.
Title: Re: A501 RAM expansion not working?
Post by: danwood on August 08, 2014, 11:26:17 AM
The battery probably leaked and corroded the board, common in these old battery-backed expansions.  Open the metal shielding and see the extent of the damage, it may or may not be repairable.

http://www.commodore-amiga-retro.com/amiga/car_0807/scuzz_501_01.jpg
Title: Re: A501 RAM expansion not working?
Post by: ddniUK on August 08, 2014, 12:44:48 PM
Quote from: danwood;770592
The battery probably leaked and corroded the board, common in these old battery-backed expansions.  Open the metal shielding and see the extent of the damage, it may or may not be repairable.

http://www.commodore-amiga-retro.com/amiga/car_0807/scuzz_501_01.jpg

(http://i.imgur.com/ZvIoJxm.png)
Title: Re: A501 RAM expansion not working?
Post by: Dr. Chef on August 08, 2014, 04:49:44 PM
Should I buy another one, or are there better ram expansions for the A500?
Title: Re: A501 RAM expansion not working?
Post by: som99 on August 08, 2014, 10:51:09 PM
Quote from: Dr. Chef;770615
Should I buy another one, or are there better ram expansions for the A500?


Kipper makes some nice ones for teh A500 :)

http://kipper2k.com/amigaforsale
Title: Re: A501 RAM expansion not working?
Post by: magnetic on August 08, 2014, 10:55:27 PM
Dr Chef did you open the case as instructed? If that batt leaked it may still be possible to recover.
Title: Re: A501 RAM expansion not working?
Post by: Dr. Chef on August 08, 2014, 11:58:17 PM
I'll try when I get home from work.
Title: Re: A501 RAM expansion not working?
Post by: Oldsmobile_Mike on August 09, 2014, 12:11:49 AM
You should still get a replacement if you plan on doing the 1M chip ram modification.
Title: Re: A501 RAM expansion not working?
Post by: Dr. Chef on August 09, 2014, 01:33:49 AM
I'll open the A501 later, right now I'm copying games to floppy for my Amiga. I want to be able to play games like Super Frog that require 1mb of ram. I don't want anything fancy or complicated to setup.

Thanks for the replies.

Edit again: What do you think about this (http://www.ebay.com/itm/Commodore-Amiga-500-Plus-half-meg-ram-expansion-tested-working-/121219580165?pt=UK_VintageComputing_RL&hash=item1c39400105) or this (http://www.ebay.com/itm/Commodore-Amiga-500-Plus-half-meg-ram-expansion-tested-working-/400611806249?pt=UK_VintageComputing_RL&hash=item5d46530c29)? I want something that isn't going to have battery issues.


Edit: I got the shielding off with all my brother help.

Here are pictures of the ram. I see what looks like damage around the battery.
http://imgur.com/a/GQF01
Title: Re: A501 RAM expansion not working?
Post by: sm3 on August 09, 2014, 05:02:55 PM
If you want a RTC and don't want to mess with soldering a replacement battery on, you might want to look for one that has the replaceable button battery on it.

Some trapdoor expansions have a soldered in rechargeable battery I think, but still, if the battery dies, you have to solder a replacement in or a battery holder for a new button style battery.

I'm sure others will have additional suggestions.

Maybe something like this: http://www.ebay.com/itm/311016244763
Title: Re: A501 RAM expansion not working?
Post by: magnetic on August 09, 2014, 10:50:23 PM
Quote from: Dr. Chef;770643

Here are pictures of the ram. I see what looks like damage around the battery.
http://imgur.com/a/GQF01


It is actually not bad at all. The batt may not be the problem...
Title: Re: A501 RAM expansion not working?
Post by: Dr. Chef on August 10, 2014, 07:08:25 AM
Quote from: sm3;770668
If you want a RTC and don't want to mess with soldering a replacement battery on, you might want to look for one that has the replaceable button battery on it.

Some trapdoor expansions have a soldered in rechargeable battery I think, but still, if the battery dies, you have to solder a replacement in or a battery holder for a new button style battery.

I'm sure others will have additional suggestions.

Maybe something like this: http://www.ebay.com/itm/311016244763

Will a standard 512k ram expansion be enough to play Super Frog and/or use Protracker?
Title: Re: A501 RAM expansion not working?
Post by: sm3 on August 10, 2014, 07:33:19 AM
Quote from: Dr. Chef;770697
Will a standard 512k ram expansion be enough to play Super Frog and/or use Protracker?

 I believe most games for the Amiga 500 were created for a 512k machine.
Title: Re: A501 RAM expansion not working?
Post by: som99 on August 10, 2014, 09:02:47 AM
Quote from: Dr. Chef;770697
Will a standard 512k ram expansion be enough to play Super Frog and/or use Protracker?


Yeah 512KB chip and fast and you have a 1MB machine and most games will run :)

There is a decent amount of 1MB games out there :)