[comp.sys.nsc.32k] anyone have thoughts re ...

news@daver.bungi.com (05/29/90)

1) whether the pc532 can get by without a fan
   (if not, what's recommended air flow ?)

2) how much trouble a pc532 causes with respect to EMI
   (Is a tightly sealed metal chassis necessary, or can I get away with
   a chassis built from popsicle sticks ?)
   The only working pc532 I've seen (Jon Loeliger's) was surrounded by so
   many other EMI generators that it was almost impossible to gather
   any meaningful data regarding EMI.

3) unexpected problems during assembly and troubleshooting ?  I've seen a
   few mentioned on this list, but given the apparently low percentage of
   pc532 owners with significant hardware experience, it seems likely that
   there are some tales worth telling.  If nothing else, I'd expect at least
   a few DOA chips, given the total number of components installed in pc532
   systmes to date.

4) Anyone have recommendations/sources for the misc. stuff (power supply,
   fan, chassis, terminals, cables, disks, etc.) that's not been included
   in the group parts buys ?  I'd be especially interested in comments about
   what to look for re power supplies. I suspect there's a fair amount of
   junk on the market, and would prefer not to find out the hard way.
   If you recommend suppliers, please include address and phone number.

Thanks!

loeliger@convex.com (Jon Loeliger) (05/29/90)

> 2) how much trouble a pc532 causes with respect to EMI
>    (Is a tightly sealed metal chassis necessary, or can I get away with
>    a chassis built from popsicle sticks ?)
>    The only working pc532 I've seen (Jon Loeliger's) was surrounded by so
>    many other EMI generators that it was almost impossible to gather
>    any meaningful data regarding EMI.

Now, now, now, he explained, tongue firmly planted in cheek, I used to
have this classic hacker scene on my desk.  You know, a real *distributed*
computing environment, everything kludged together, nothing packaged,
loose wires and cables all over the place, the hip-bone connected to the
thigh-bone and the turbo charger installed.  That was back when it worked.
Now-a-days, I've got it neatly packaged in an AT case, my own, unborrowed
power supply, almost proper cabling, and no extra trash.  It looks real clean.
That's when the disks stopped working...

> 3) unexpected problems during assembly and troubleshooting ?  I've seen a
>    few mentioned on this list, but given the apparently low percentage of
>    pc532 owners with significant hardware experience, it seems likely that
>    there are some tales worth telling.  If nothing else, I'd expect at least
>    a few DOA chips, given the total number of components installed in pc532
>    systmes to date.

Not exactly an answer to the queston, but, perhaps it is time to drag the
updated version out of fluxes and distribute it so you know who to bug
directly!

Here's Jon's definitive list of claimed working systems:

	The Few, The Proud, The Living
	------------------------------

	Who			Really Who
	---			----------
	John Connin		tarpit!manatee!johnc
	Sverre Froyen		mips!fesk.seri.gov!sverre
	Bdale Garbee		bdale@col.hp.com
	Jordan Hubbard		jkh@meepmeep.pcs.com
	Ron Irvine		ron@hcr.com
	Robbin Johnson		rjohnson@kiwi.mpr.ca
	Jon Loeliger		loeliger@convex.com
	Peter P			pp@prosys.se
	Dave Rand		dlr@daver.bungi.com
	Fred's Schneider	K0YUM
	Karl Swartz		uunet!apple!zygot!ditka!kls
	George Scolaro		george@wombat.bungi.com
	Desmond Young		des@dtg.nsc.com
	Bruce Culbertson	culberts@hplwbc.hpl.hp.com>

	some other German board noted by Jordan (who's?)

As usual, if you aren't on the list and you want to be and your board
suddenly springs to life one dim 3 AM, send me a piece of mail or post
your exuberance to the pc532 list and I'll add you to the list of The Few,
The Proud, The Living.




jdl

bdale@col.hp.com (Bdale Garbee) (06/02/90)

> Here's Jon's definitive list of claimed working systems:

> 	The Few, The Proud, The Living
> 	------------------------------

> 	Who			Really Who
> 	---			----------
> 	John Connin		tarpit!manatee!johnc
> 	Sverre Froyen		mips!fesk.seri.gov!sverre
> 	Bdale Garbee		bdale@col.hp.com
> 	Jordan Hubbard		jkh@meepmeep.pcs.com
> 	Ron Irvine		ron@hcr.com
> 	Robbin Johnson		rjohnson@kiwi.mpr.ca
> 	Jon Loeliger		loeliger@convex.com
> 	Peter P			pp@prosys.se
> 	Dave Rand		dlr@daver.bungi.com
> 	Fred's Schneider	K0YUM

Fred is reachable as k0yum%winfree.uucp@col.hp.com, though the packet radio
link that forwards his mail to him is down right now.  He and I have been
getting together pretty regularly on Sundays to dink with things...

Bdale

bdale@col.hp.com (Bdale Garbee) (06/05/90)

> 1) whether the pc532 can get by without a fan
>    (if not, what's recommended air flow ?)

We mounted our PC532 boards in PC tower cases, which normally have fans on the
power supply only, exhausting air from high in the box.  The CPU/FPU seemed
to be running warm, so I added a 12V, about 25CFM fan to the bottom front of
the box, in a space apparently intended for this purpose (holes in the right
places, physical perfect fit between the sheet metal of the case and the plastic
front, etc), and everything runs *much* cooler now.  I would suggest some form
of airflow inducement over the CPU/FPU combo.

> 2) how much trouble a pc532 causes with respect to EMI
>    (Is a tightly sealed metal chassis necessary, or can I get away with
>    a chassis built from popsicle sticks ?)
>    The only working pc532 I've seen (Jon Loeliger's) was surrounded by so
>    many other EMI generators that it was almost impossible to gather
>    any meaningful data regarding EMI.

Ditto for mine, plus I've not yet run it with the cover on, and am not likely
to in the near future... my "Bit Basement" is an RF nightmare anyway, with
transmitters on at least 3 amateur radio bands going 24hrs/day, and loads of
computer gear...

> 3) unexpected problems during assembly and troubleshooting ?  I've seen a
>    few mentioned on this list, but given the apparently low percentage of
>    pc532 owners with significant hardware experience, it seems likely that
>    there are some tales worth telling.  If nothing else, I'd expect at least
>    a few DOA chips, given the total number of components installed in pc532
>    systmes to date.

No DOA chips on the two boards I have been involved with (mine and Fred 
Schneider's)... but as reported earlier, we did get some bad 50Mhz oscillators.
That was easy to find, as the first thing I checked when nothing worked was
the osc, and it was flatlined... am running a 40Mhz osc right now, no incentive
yet to buy a 50Mhz part.

In my case, at least, there's lots of hardware knowledge.  But the design of
the board is good enough that it's a non-issue.  Other than a bad osc, we used
my normal board assembly practices, and everything just works great!

> 4) Anyone have recommendations/sources for the misc. stuff (power supply,
>    fan, chassis, terminals, cables, disks, etc.) that's not been included
>    in the group parts buys ?  I'd be especially interested in comments about
>    what to look for re power supplies. I suspect there's a fair amount of
>    junk on the market, and would prefer not to find out the hard way.
>    If you recommend suppliers, please include address and phone number.

Buy a PC tower case with supply, and you're set.  Any of the AT cases and power
supplies should work fine.

Bdale

levy@nsc.nsc.com (Jonathan Levy) (06/05/90)

In article <9006042014.AA14006@hpcsbg.col.hp.com> bdale@col.hp.com (Bdale Garbee) writes:
>> 1) whether the pc532 can get by without a fan
>>    (if not, what's recommended air flow ?)
>We mounted our PC532 boards in PC tower cases, which normall. In all
>power supply only, exhausting air from high in the box.  The CPU/FPU seemed
>to be running warm, so I added a 12V, about 25CFM fan to the bottom front of

I have worked with systems which incorporated the 532, GX32,
and GX320 (yes, the newly announced CPU, code name Barracuda). In
all the CPU/FPU tend to get very hot to touch, 
but none the less, work flawlessly
at room temperature with no fan. The 532 on my desk used to work
for days on end at 30Mhz with no problems. We also have a GX32 
system running MicroSoft/Bauer Postscript compatible PDL at 30Mhz 
with no fan. This system is very reliable. 

This is not to say that a fan is not a good idea, but to reasure
you that it is quite normal for the 532/381 to get hot. 

Jonathan

gs@vw25.chips.com (George Scolaro) (06/06/90)

[In the message entitled "Re: anyone have thoughts re ..." on Jun  5, 16:37, Jonathan Levy writes:]
> 
> and GX320 (yes, the newly announced CPU, code name Barracuda). In
> 
> Jonathan

Why not tell us more about the new chips - I wont even call it advertising!
Besides, I'm sure you're dying to.....

thanks,

-- 
George Scolaro (gs@vw25.chips.com)	Chips & Technologies
+1 408/434-0600 X4556 work		3050 Zanker Road
					San Jose, CA  95134