Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!RADC-LONEX.ARPA!koziarzw
From: koziarzw@RADC-LONEX.ARPA
Newsgroups: comp.sys.zenith.z100
Subject: (none)
Message-ID: <8807151829.AA02236@radc-lonex.arpa>
Date: 15 Jul 88 18:29:06 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
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Mail to:	info-hz100@radc-tops20.arpa	Date: Fri Jul 15 14:28:15 1988
From: koziarzw@radc-lonex.arpa
Sender: koziarzw@radc-lonex.arpa
Subject:	HZ100+Z217 with OLD power supply
cc:		none
Message:

I thought that some of you other Z100 persons might find this item of benefit.
Some time ago, Gern posted a description of the HZ100 power supply and mentioned
that there was no (apparent) difference between the old (BLACK CASE) and
the newest (GOLD CASE) powersupplies, except that the older supplies lacked
the four conductor cable leading to the Z-217 card.

If you have access to a Winchester, a Z-217 controller, and data seperator
but your Z100 has an old power supply, you can add the cable required.  BE
SURE YOU ARE CAREFUL WHEN WORKING ON THE POWER SUPPLY, THEY ARE VERY EXPENSIVE
TO REPLACE!!!!!!!!!!!!!!!!!  Using Gern's posted power supply description,
the power supply schematic, the Z100 technical manual and good judgement
and common sense procede as follows:

1)  Remove the power supply from the Z100

2)  Remove the power supply cover

3)  Locate the area of the power supply circuit board to which all the RED
    WIRES lead, this where you will add one or two wires.

    a)  Using a SMALL drill, (to accomodate a 18AWG wire) drill two holes
        in the SAME AREA OF COPPER AS ALL THE OTHER RED WIRES are soldered
        to.  Alternatively, you can drill one larger hole to accommodate
        one 12AWG wire.

    b)  Using STRANDED wire, solder one or two pieces into the holes you
        just drilled.  They should have RED insulation!!!!!

    c)  Locate the two EMPTY circuit board holes for GROUND wires.

    d)  Insert and solder one piece of BLACK INSULATED 18(or larger)AWG wire
        into each of these empty holes (you may first need to clean the holes
        of solder; use a 'solder sucker', a solder wick, or any other de-solder
        tool that you might have) 

4)  You have added two ground return wires (BLACK INSULATION) and one (12AWG)
    or two (18AWG) RED insulated +5V. wire(s)

5)  Re-assemble the power supply cover and re-install the power supply in
    the Z100.  BE CAREFULL TO AVOID SHORT CIRCUITS!!!!!!!!!  PUT NEW HEAT
    GREASE ON THE SMALL VOLTAGE REGULATORS THAT FASTEN TO THE POWER SUPPLY
    HOUSING!!!! 

6)  Obtain from any local electronics supplier the necessary connector. 
 
    a)  The wires are installed in RED, BLACK, BLACK, RED into the connector.

    b)  Turn on the computer and verify +5V at the RED wires.  

7)  If any part of this discussion does not sound like something you want
    to, then DO NOT DO IT!!!!!!  This should be performed only by persons
    familiar with printed circuit board modification/maintenance procedures.

I hope that this description is sufficient to allow those with old power
supplies to add winnies to their systems,  I did indeed perform the addition
described here-in on my own machine with no ill effects.  Please bear in
mind that I have printed circuit board experience (I am E.E. and Elec. Tech.)

Cheers,

Walt K.