Help! anything about a 3000T

[danbeaver]

I assume the Key-switch had an Open-Closed connection (Closed locks out the keyboard and mouse) and a Reset connection built in (closed causes a hardware reset). I've not run across such a combination; good luck on finding that one... But no, they have no bearing on the PSU; rather than find an exact replacement have you thought about: 1) having that one repaired (it is old school tech and a TV repair place should be able to fix it), 2) replacing the insides with a new, and smaller PSU, or 3) finding a similar "box" and grafting the wiring harness?
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Amiga 3000T Power Supply Connector

This is a description of the power supply connector ON THE MOTHERBOARD of the Amiga 3000T
series.



PIN Description PIN Description
1 TICK 13 FAIL
2 -12V 14 +12V
3 -5V 15 +12V
4 GND 16 +5V USER
5 GND 17 GND
6 GND 18 GND
7 GND 19 GND
8 GND 20 GND
9 +5V 21 +5V
10 +5V 22 +5V
11 +5V 23 +5V
12 +5V 24 +5V

Taken from the Amiga 3000T Schematics in the back of every Amiga 3000T manual.

These voltages are found on standard AT power supplies. Tick is not found on modern PSU’s and a motherboard jumper (J300 on an A2000) sets it to internal

Pictures can be found here:
http://www.allpinouts.org/index.php/File:Connector_amiga3000tpower.png

http://aijaa.com/img/b/00601/5622021.jpg

http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=998

http://media.bestofmicro.com/Power-Supply-Fundamentals,8-2-312626-13.jpg

[tone007]

http://amigakit.leamancomputing.com/catalog/product_info.php?cPath=39&products_id=1164

This would be nice if it were for the 3000T, unfortunately the 3000 desktop PSU has a different connector.

I ended up wiring up an AT PSU (fit nicely inside the original 3000T PSU's case) using the pinout in the previous post and it worked fine.

edit: I could be mistaken (it's been a couple of years,) but I believe the actual connector on the 3000T board is the same used for 24-pin ATX power supplies. I seem to recall buying a brand new harness to use instead of cutting the old one off of the original PSU.

[mdivancic]

If you can find a European supply, it can be converted to US voltages:

http://www.amiga.org/forums/showthread.php?t=22791

[Castellen]

If you're confident working on electronics and mains voltages, these power supplies are easy enough to repair.  These switchmode supplies all operate on the same principle of rectifying the mains to a DC voltage then pulse width modulation switching it through a high frequency transformer.  Often different makes/models have common issues of input bridge rectifier and/or switching transistor failure, which usually fail to a short circuit state.  Equivalent parts are usually cheap and easy to source.  I've written various notes on generic power supply repair on this page under 'A3000 power supply common faults'.

Those notes are written around 230VAC supplies.  For 110VAC, reservior capacitor DC voltages should be around (110V/sin(45))-1.2 = 154V.

When you say the supply is dead, I gather the fan is not running and there's no 5V output to the main board?

As for the keyswitch, it won't prevent booting if it's in the locked state.  It only disables keyboard input and mouse movement (not mouse buttons).  If unsure, disconnect the keyswitch connector at the main board which leaves the machine in an 'unlocked' state.

[VingtTrois]

After more than a year, I am able to solve the problem about the Keylock

This keylock is a piece of "poop" ! It can open itself at any time and PINs may fall into the Amiga. Replace it asap if you can. Otherwise, in the meantime, if you want to enjoy your AMIGA while the keylock is broken, here are the details below.

[size=+3]The schematic of the A3000T[/size]



[size=+3]The keylock: the front panel of the A3000T (front)[/size]


Click to enlarge the picture


[size=+3]The keylock: the front panel of the A3000T (rear)[/size]


Click to enlarge the picture


[size=+3]The keylock: cable from the motherboard[/size]




[size=+3]The keylock: 2 wires for Keylock On/Off and 2 wires for Reset[/size]




[size=+3]The keylock: connector details[/size]


((Blue wires connected to the motherboard on connector named CN302))

[size=+2]Connect the Red & Black wires (at the center) to enable AMIGA. Shorting the two wires (at right) each time you want to make a Reset.[/size]