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Author Topic: What on earth is going on here ?  (Read 255 times)

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Offline scuzzb494Topic starter

What on earth is going on here ?
« on: January 16, 2018, 10:28:09 PM »
Hi

I am bewildered somewhat with what I discovered today lurking inside an Amiga 500. It is either a work of Amiga art or a mess. I cannot fathom myself. The switch to the arrangement doesn't appear to do anything.

http://www.scuzzscink.com/amiga/scuzzblog_january18/scuzzblogdjanuary18_1603.htm

If you have any ideas at all maybe you could share them with me so I can update the webpage.

Many thanks

Offline UberFreak

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Re: What on earth is going on here ?
« Reply #1 on: January 17, 2018, 12:57:02 AM »
That looks like a 1.5MB expansion.
The Gary adapter is required to access the additional 1MB, thats a typical setup like any other >512K expansion I've seen so far.
 

Offline Vlabguy1

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Re: What on earth is going on here ?
« Reply #2 on: January 17, 2018, 01:06:44 AM »
Quote from: scuzzb494;835064
Hi

I am bewildered somewhat with what I discovered today lurking inside an Amiga 500. It is either a work of Amiga art or a mess. I cannot fathom myself. The switch to the arrangement doesn't appear to do anything.

http://www.scuzzscink.com/amiga/scuzzblog_january18/scuzzblogdjanuary18_1603.htm

If you have any ideas at all maybe you could share them with me so I can update the webpage.

Many thanks


Cool stuff.  At least she works.

R.
 

Offline magnetic

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Re: What on earth is going on here ?
« Reply #3 on: January 17, 2018, 01:16:04 AM »
lol that is what you call a butcher job... man only amiga guys lol
bPlan Pegasos2 G4@1ghz
Quad Boot:Reg. MorphOS | OS4.1 U4 |Ubuntu GNU-Linux | MacOS X

Amiga 2000 Rom Switcher w/ 3.1 + 1.3 | HardFrame SCSI | CBM Ram board| A Squared LIVE! 2000 | Vlab Motion | Firecracker 24 gfx

Commodore CDTV: 68010 | ECS | 9mb Ram | SCSI -TV | 3.9 Rom | Developer EPROMs
 

Offline scuzzb494Topic starter

Re: What on earth is going on here ?
« Reply #4 on: January 17, 2018, 02:29:52 AM »
Quote from: magnetic;835070
lol that is what you call a butcher job... man only amiga guys lol


Odd really. I kinda get the card and the Gary, but the wires to the right and the sticky glue on everything. And I can't still fathom what the switch does.. cus nothing happens.

Offline Castellen

Re: What on earth is going on here ?
« Reply #5 on: January 17, 2018, 07:16:47 AM »
Quote from: scuzzb494;835073
Odd really. I kinda get the card and the Gary, but the wires to the right and the sticky glue on everything. And I can't still fathom what the switch does.. cus nothing happens.




Given that the capacitors providing negative feedback to the op-amps have been cut, as have the capacitors in the anti-aliasing filter, you get the impression that someone didn't really know what they're doing.  The wires running to that switch suggest some attempt to make the anti-aliasing (low pass) audio filter switchable.  But given that some of the components the filter needs to work have obviously been cut, I doubt if it would work as expected.

The wires running to the memory expansion are probably address lines as required by the additional memory.

The hot glue on the PLCC socket is some bad attempt to fix the socket after someone has tried removing the IC using a crowbar.

And the hot glue covering everything else is anyone's guess.....
 

Offline bbond007

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Re: What on earth is going on here ?
« Reply #6 on: January 17, 2018, 06:32:52 PM »
Quote from: Castellen;835077
Given that the capacitors providing negative feedback to the op-amps have been cut, as have the capacitors in the anti-aliasing filter, you get the impression that someone didn't really know what they're doing.  The wires running to that switch suggest some attempt to make the anti-aliasing (low pass) audio filter switchable.  But given that some of the components the filter needs to work have obviously been cut, I doubt if it would work as expected.

The wires running to the memory expansion are probably address lines as required by the additional memory.

The hot glue on the PLCC socket is some bad attempt to fix the socket after someone has tried removing the IC using a crowbar.

And the hot glue covering everything else is anyone's guess.....

What a mess with all that hot glue...

Perhaps the resistors for the audio are inside the shrinkwrap? Maybe it works...