🚀 go-pugleaf

	I have been attempting to add EMS memory to my Z-159.  Silly me,
	I thought you could just add memory and flip a few switches.
	Here is actually what you need to do:

	From kent@uflorida (thanks!) there are missing chips on the old
	Z-159 memory boards (always wondered what was supposed to go there)
	and you need to add then in addition to the DRAM and flip the dips.

	Parts: U432,433 - 74LS670
	       U435     - 74LS244
	       U451     - 74ALS74
	       U455     - PAL ZDS P/N 444-499

	All but the last chip are easily available from Frys (or your local
	DRAM and Nacho Chip shop).  I talked to a zenith salesperson about
	EMS, he only could tell me what was on the sheet in front of him:
	a $113 memory board with the chips installed.  So I called Zenith in
	San Jose and asked about buying the chip.  After being on hold for
	several minutes, the rep told me that I could get a full chip upgrade
	(with 256K!!!) for the low price of $199.  No I insisted, I ONLY want
	the PAL.  "Are we installing it?"  No, I'll do it myself.  The PAL
	alone was $10.50, but there is a $100 Core charge if you don't give
	Zenith back your old PAL, BUT I NEVER GOT ONE IN THE FIRST PLACE.
	"Hmm, guess we're back to square one."  Yeah, ok, thanks...

	My next gambit is to find a repair center and connive them into
	selling me the chip.  Otherwise, could someone post the PAL source
	so I can burn one in myself (:-) 

-------

	John M Vinopal	banshee@ucscf.UCSC.EDU	ucbvax!ucscc!ucscf!banshee

In article <22275.25dc6dd8@kuhub.cc.ukans.edu>, arritt@kuhub.cc.ukans.edu writes:
> I'm in the market for a 386sx, and our state contract says "thou
> shalt buy Zenith and no other".  The Zenith 386sx has a 120 watt
> power supply, which seems unreasonably small.  The Zenith sales
> rep said they use some special chips which reduce the power

  Ack!  special chips?  I happen to have a Z386sx power supply here, the
ratings are as follows:

	+5v  14A
	+12v 4A
	-12V .5A

  Now lets look at the load of a typical computer.  First off, the main 
board, fully loaded with 8 megs of RAM, coprocessor, etc. proabably takes
around 4 amps of the 5V line with around 100 ma on the +-12v lines.  I'm
guessing on the high side here.  That leaves 10A @ 5V for the slots.  One
slot has a VGA card, less than an amp @ 5V.  That leaves you with slightly
more than 2 amps @ 5v per slot, plenty for most cards.  The drives take
small amounts of current @ 5v, maybe an amp for all three.  The drives
do require maybe 1.5 amps from the 12v line, more for startup.
  This just about fits the supply ratings above.

> Anyway, my questions to you fellow netters:  Does anyone have 
> experience with these units (or other Zeniths with very small
> power supplies)?  Is this a practical consideration?  What happens
> if I add a tape backup, a transputer board, maybe a few more
> megabytes of memory, or other electrical load?

  Well, I have a little experience with Zenith units ;^).  The 
transputer boards could draw quite a bit of current.  Most
other AT type boards will be okay.

> Ray Arritt                        | 



	Jeff Easton			Zenith Data Systems
	Systems Engineer		OEM Engineering
	easton@andrews.edu     --or--
	easton@zds-oem.zds.com
	 I'd rather be Water Skiing...
 

In article <1391@darkstar.ucsc.edu>, usenet@darkstar.ucsc.edu (Usenet News Account) writes:
> 
> 	I have been attempting to add EMS memory to my Z-159.  Silly me,
> 	I thought you could just add memory and flip a few switches.
> 	Here is actually what you need to do:
> 
> 
> 	My next gambit is to find a repair center and connive them into
> 	selling me the chip.  Otherwise, could someone post the PAL source
> 	so I can burn one in myself (:-) 
> 

  Call Heath parts replacement at 616-982-3571, give them the part
number.  They will be happy to sell you just the PAL.

> 	John M Vinopal	banshee@ucscf.UCSC.EDU	ucbvax!ucscc!ucscf!banshee


	Jeff Easton			Zenith Data Systems
	Systems Engineer		OEM Engineering
	easton@andrews.edu     --or--
	easton@zds-oem.zds.com
	 I'd rather be Water Skiing...