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From: bdale@col.hp.com (Bdale Garbee)
Newsgroups: comp.sys.nsc.32k
Subject: Re: anyone have thoughts re ...
Message-ID: <9006042014.AA14006@hpcsbg.col.hp.com>
Date: 4 Jun 90 20:14:33 GMT
Sender: news@daver.bungi.com
Lines: 51
Approved: news@daver.bungi.com

> 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