English Amiga Board


Go Back   English Amiga Board > Support > support.Hardware

 
 
Thread Tools
Old 10 March 2020, 23:49   #1
Unicorn
Registered User

 
Join Date: Mar 2020
Location: Sydney, Australia
Posts: 49
A3000T Rebuild

So I have an A3000T that was given to me some years back.

Some users here have convinced me it is worthwhile to get it up and running again.

The machine seems to have the latest buster agnus etc, it seems to have 2MB chip ram and either 2mb or 4mb fast ram.

It has a standard sized PC power supply hiding inside the case of the A3000T power supply. The power connector is not connected to MB also the Battery was removed years ago.

The mains cable runs to the power switch on the front.

Unfortunately the keyboard switch fell apart when touched.

Does anyone know of a replace barrel switch.

Does anyone have a photo of the power connector colours to confirm the voltage is going to the right pins.

Thanks
Unicorn is offline  
Old 11 March 2020, 12:33   #2
mousehouse
Registered User

 
Join Date: Sep 2019
Location: Netherlands
Posts: 49
Hi!

Good project to bring an Amiga 3000T back to life, really nice machines IMHO.

Attached a photo of my 3000T where you can see the colours to the MB from the power supply. I also have the service manual somewhere that I could put in the Zone for you if you do not have it.

PSU pins should be : http://www.hardwarebook.info/Amiga_3000T_Power_Supply

As for battery, I soldered two wires to the bottom of the PCB on the battery pins and connected a 3.6V phone battery pack. Works like a charm. I'm sure I have pictures of that as well somewhere...
Attached Thumbnails
Click image for larger version

Name:	IMG_1585.jpeg
Views:	62
Size:	581.5 KB
ID:	66432  
mousehouse is offline  
Old 11 March 2020, 13:07   #3
Unicorn
Registered User

 
Join Date: Mar 2020
Location: Sydney, Australia
Posts: 49
Quote:
Originally Posted by mousehouse View Post
Hi!

Good project to bring an Amiga 3000T back to life, really nice machines IMHO.

Attached a photo of my 3000T where you can see the colours to the MB from the power supply. I also have the service manual somewhere that I could put in the Zone for you if you do not have it.

PSU pins should be : http://www.hardwarebook.info/Amiga_3000T_Power_Supply

As for battery, I soldered two wires to the bottom of the PCB on the battery pins and connected a 3.6V phone battery pack. Works like a charm. I'm sure I have pictures of that as well somewhere...
Great thanks.

I found a comparison of atx and A3000t pins but I just don't know who has done what to this machine. I don't want to kill the machine first go.

I am not sure what the white fuz is on the board, but I have to remove the board to find the bits of the keyboard lock.

I think I also have a cyberstorm MK I and MKII around somewhere.
Unicorn is offline  
Old 11 March 2020, 13:33   #4
mousehouse
Registered User

 
Join Date: Sep 2019
Location: Netherlands
Posts: 49
If you take the system apart anyway, probably a good idea to do the INT2 modification (run a wire on the back side of the motherboard between the CPU slot and another pin on the CIA's I believe). That way SCSI on the accelerators works ;-) Let me know if you need to know which pins, I have photo's from mine.
mousehouse is offline  
Old 11 March 2020, 14:18   #5
DarrenHD
Registered User
 
Join Date: Aug 2008
Location: London / Canada
Posts: 539
Quote:
Originally Posted by Unicorn View Post
Great thanks.

I found a comparison of atx and A3000t pins but I just don't know who has done what to this machine. I don't want to kill the machine first go.

I am not sure what the white fuz is on the board, but I have to remove the board to find the bits of the keyboard lock.

I think I also have a cyberstorm MK I and MKII around somewhere.
I recently got a used A3000 and it also had alot of white fuzz, lots around the CPU fast slot, and in other places. The battery had leaked in this A3000 and it also had green residue in many places. I cleaned as much of it off as I could. The white fuzz came off pretty easy with isopropyl alcohol. For the green stuff I used vinegar, distilled water, and isopropyl alcohol. Most of it came off. It's clear though that it's "old" and you can really see the metal fatigue/age on the chip pins. Luckily most of it still works - I have an issue with Amber(flickerfixer) not displaying some resolutions properly but that is probably easily fixed by replacing a few chips, and of course the clock doesn't hold time, although the system does find the clock (check with SysInfo, it should say "Clock Found!". I'm sending it out to be repaired as I've done as much as I can with it myself.

The MKII should work fine in the A3000(T), check for jumper settings - google it and you will find it.

Bottom line, be very careful and patient working around the board. Due to the age they are pretty fragile and the metal pins on the chips can easily break (I've broken pins off one of the chips myself . Also use the proper tools if you are going to be pulling chips out of sockets...otherwise there is a huge risk you will break a pin.

Darren
DarrenHD is offline  
Old 11 March 2020, 14:20   #6
Hedeon
PPC Hacker

 
Join Date: Mar 2012
Location: Leiden / The Netherlands
Posts: 1,216
Quote:
Originally Posted by mousehouse View Post
If you take the system apart anyway, probably a good idea to do the INT2 modification (run a wire on the back side of the motherboard between the CPU slot and another pin on the CIA's I believe). That way SCSI on the accelerators works ;-) Let me know if you need to know which pins, I have photo's from mine.
I only just now noticed that there is a lot of conflicting info on the presence of the INT2 signal at the A3000T CPU slot.
Hedeon is offline  
Old 11 March 2020, 15:41   #7
Jope
-
Jope's Avatar
 
Join Date: Jul 2003
Location: Helsinki / Finland
Age: 39
Posts: 7,771
INT2 was not present in my A3000T at least.
Jope is online now  
Old 11 March 2020, 18:03   #8
mousehouse
Registered User

 
Join Date: Sep 2019
Location: Netherlands
Posts: 49
Quote:
Originally Posted by Jope View Post
INT2 was not present in my A3000T at least.
Same here... Did the fix when I got the machine ~8 years ago (?)
mousehouse is offline  
Old 11 March 2020, 18:54   #9
Hedeon
PPC Hacker

 
Join Date: Mar 2012
Location: Leiden / The Netherlands
Posts: 1,216
See for example https://www.bigbookofamigahardware.c...uct.aspx?id=22

Which says:

INT2 Modifications

Certain accelerators, primarily those with onboard SCSI may require the INT2 modification to function fully. The A3000's CPU Fast Slot does not contain the INT2 signal as found on the A3000T, A4000 and A4000T. An INT2 modification guide can be found here.

Well, I guess one has to check.
Hedeon is offline  
Old 12 March 2020, 06:45   #10
Unicorn
Registered User

 
Join Date: Mar 2020
Location: Sydney, Australia
Posts: 49
Quote:
Originally Posted by Hedeon View Post
See for example https://www.bigbookofamigahardware.c...uct.aspx?id=22

Which says:

INT2 Modifications

Certain accelerators, primarily those with onboard SCSI may require the INT2 modification to function fully. The A3000's CPU Fast Slot does not contain the INT2 signal as found on the A3000T, A4000 and A4000T. An INT2 modification guide can be found here.

Well, I guess one has to check.
Now I have to wonder does the 3000T have the INT2 mod. My guess is this machine was well looked after until the power supply failed. So I guess it would have been done if needed.

It has the latest IC's on it. The funny fail seems to be that someone did all of the work to build a new power supply. Looking at the wire colours referenced earlier it looks good. BUT, the power supply does not reach to the connector. I think it was a FML moment that stopped the repair of the machine.

So I can possibly just get an ATX extender to bridge the gap.
Unicorn is offline  
Old 12 March 2020, 19:17   #11
Wrangler
Registered User

 
Join Date: Sep 2015
Location: London, UK
Posts: 317
I've tried using an ATX power supply (with significant amps on the 5v line) with an A3000T via an adaptor I made, but the machine struggled to get enough power even to display the insert floppy screen without video corruption! I have a feeling the power socket on the motherboard had corroded a bit so that is something to watch. Curious whether it's OK or not for you.
Wrangler is offline  
Old 12 March 2020, 22:16   #12
Unicorn
Registered User

 
Join Date: Mar 2020
Location: Sydney, Australia
Posts: 49
My A4000 converted to a tower has been running many years trouble free on an ATX power supply well 2 one died and was replaced.

That machine has 16MB ram plus Power PPC +128MB of ram, BVision, AriadneII, Vlab Motion, Tocatta, Emplant and 5 9GB SCSI drives.

I pulled the power supply out of A3000T to see if I can get it to reach the connector. I can also research its model and ratings.

I could hack the hole the standard A3000T power cables come out of to get the length right.

My guess is that this is a an AT power supply with the A3000T 24 pin connector on it.

Pin 1 seems to be wrapped into the cables but not connected, this I assume is the tick.

I wil get the board out and clean it over the weekend.
Unicorn is offline  
Old 14 March 2020, 04:11   #13
AmigaHope
Registered User
 
Join Date: Sep 2006
Location: New Sandusky
Posts: 642
Treat that machine well. A3000Ts are rare and are probably C='s finest hour in Amiga design.
AmigaHope is offline  
Old 16 March 2020, 01:18   #14
Unicorn
Registered User

 
Join Date: Mar 2020
Location: Sydney, Australia
Posts: 49
I actually found the A3000T power supply from this machine. The person who owned it had desoldered the A3000T connector from the powersupply.

I noticed it due to commodores orange leads on the molex plugs.

The question then is should I rebuild the original power supply or try and adapt a PC power supply.

I also found 10 Milk crates of big box Amiga Programs. Who says hoarding can't be fun.
Unicorn is offline  
Old 16 March 2020, 02:38   #15
dalek
Registered User

 
Join Date: Nov 2014
Location: NSW/Australia
Posts: 363
I'd recommend Ian's ATX adapter and a new PC ATX PSU transplanting the internals in to your old 3000T PSU housing. I've used Ian's adapters in a few projects now and they are by far an away the best solution.

http://www.ianstedman.co.uk/Amiga/de...x_adaptor.html
dalek is offline  
Old 17 March 2020, 04:19   #16
Unicorn
Registered User

 
Join Date: Mar 2020
Location: Sydney, Australia
Posts: 49
Quote:
Originally Posted by dalek View Post
I'd recommend Ian's ATX adapter and a new PC ATX PSU transplanting the internals in to your old 3000T PSU housing. I've used Ian's adapters in a few projects now and they are by far an away the best solution.

http://www.ianstedman.co.uk/Amiga/de...x_adaptor.html
Unfortunately it seems ordering is not available for the moment.

I might be able to use an extender for the moment.

Darren
Unicorn is offline  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
CD32.co.uk - the rebuild project earok project.CD32 Conversion 44 02 March 2019 12:57
Please help me rebuild a amiga 600. bytestorm support.Hardware 7 06 December 2017 18:49
My A4000 rebuild RMK Hardware pics 10 07 February 2012 02:36
my 1200 tower rebuild johnim Hardware pics 8 20 July 2011 23:58
Got to Rebuild my A1200 Parsec support.Apps 0 15 July 2003 00:09

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 20:43.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Page generated in 0.24295 seconds with 14 queries