Re: Microdigital TK2000-II PSU

[mjmahon@aol.com (Michael J. Mahon)]

Richard Kilpatrick replied:

>On 3/8/04 6:55 pm, in article 20040803135530.23951.00003103@mb-m28.aol.com,
>"Michael J. Mahon" <mjmahon@aol.com> wrote:
>
>> I'm a bit suspicious of your identifications.  The provision of three +12
>> lines and only two +5 lines is strange, since the +5 current is usually
>> higher than the +12.  And there is no -12v!  Real Apples need -12, and
>> if a negative supply is omitted, it is usually -5, since it can be easily
>> produced by regulating down from -12.
>
>Errr, there is -12v. Pin 4. There are two +12v, I've marked three +12v and
>two +5v because I think that where soldered, there are either pins on that
>connector that are siamesed to accept different types of DIN connector, or
>the soldering is crap. I suspect the former.
>
>What the motherboard actually gets is -12v, 2 x +12v, one ground, one +5v :)

Ack.  Presbyopia + small font = missed "-".  ;-)

Still, try measuring continuity from the slot connector and you will
have an unambiguous reference.  (You will also probably find a 7905
regulator on the board.)

On the slot connector (which is numbered from 1 to 25 from front to
back on the right side of the connector and from 26 to 50 from back
to front on the left side--with the keyboard end toward you):

25 = +5
26 = Gnd
33 = -12
34 = -5
50 = +12

If those check out, then you should feel confident about connecting
power.

-michael

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