Geoff, Abd-ul Rahman or others following this thread,
        first I am curious about the comments on routing to a single layer
unplated pad. I have single layer unplated pads in most everyone of our
designs and find no problem routing to them, what is your comment based
upon, I just don't see it under my circumstances.
        Secondly there are sometimes valid reasons for single-layer pads w/
unplated holes. In our case we have 'feed-thrus' which pass signals from one
machined cavity in our assembly to another, a board may have up to a dozen
of these which are soldered after placing the PCB in place. They are made
unplated to allow easier de-soldering during assembly, test and servicing of
the units. I can't imagine having to remove one of these boards if the holes
were all plated, you could virtually never do it without damaging at least
one hole. Secondly the nature of the feed-thrus and the PCB carrier mean
that we cannot have any solder flowing through to the bottom side of the PCB
or our reliability with thermal extremes goes out the window because of
solder shorts. Now this problem is unique to our microwave designs but it
means that I used unplated single-sided pads in most every PCB design.
        The only shortcoming that I know of in Protel with the use of these
pads shows up in P99SE where some rocket-scientist at Protel decided that a
single-sided (non-padstack) un-plated or plated hole is not a valid drill
point and shouldn't be included in the drill drawing symbol generation. This
had worked in previous versions until P99 or P99SE. I have to experiment
over the next few days and see if I can adequately accomplish all my needs
with a multi-layer padstack and still get a drill symbol. I can't understand
why someone at Protel would decide that a drill is not a drill and so not
generate a symbol.
        During the interim I have had to temporarily change these pads to
multi-layer while generating the drill drawing, yuck, I hate doing these
sort of things. If we forget to change them back we have many other errors
which may pop up in the next set of edits to the design.

Sincerely,

Brad Velander
Lead PCB Design
Norsat International Inc.
#100 - 4401 Still Creek Dr.,
Burnaby, B.C., Canada.
V5C6G9.
voice: (604) 292-9089 (direct line)
fax:    (604) 292-9010
email: [EMAIL PROTECTED]
www: www.norsat.com


-----Original Message-----
From: Geoff Harland [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, March 13, 2001 7:23 PM
To: Protel EDA Forum
Subject: Re: [PEDA] Use Pad Stack


> At 11:17 AM 3/14/01 +1100, Geoff Harland wrote:
<SNIP>
 If you have the right equipment, and keep it in proper
order, de-soldering such components is less of a hassle than is otherwise
the case.)
<SNIP>
I concur that this method should work, but my sentiment is that it should
not be necessary to have to use two pads; I would prefer that I could
configure just *one* pad as required.

> Or one could use a single padstack with pads defined in a similar way.

If the pad's plated property is set false, I think that there would be
problems with routing to it. 
<SNIP>

Regards,
Geoff Harland.
-----------------------------

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