gEDA-user: Hello, Bills missing transistors and Attribute questions

[Mark <markzb@xxxxxxxxx>]

Hi Everyone

Thanks so much for looking!

My names Mark and I am from Malaysia. Im a newbie and
recent convert to the world of gEDA and have been
really struggling trying to understand it all! I must
have put in about 2 solid weeks of reading most of the
gschem documentation. Slowly slowly I am figuring it
out! I think one of the big problems is more that I am
from a mechanical background and have little to non
experience with EDA.

Having said that, I really like the interface of
gschem and hope to be able to get to use it well!
Anyhows.... I am writing in to you all with the hope
that some kind souls could help with a few things...

The first thing is that when one looks thru Bill
Wilson's really helpful gsch2pcb_Tutorial, there is a
link to a library of transistor symbols and elements
that Bill created. The URL is in the "Custom File
Elements" section of the document:
http://www.geda.seul.org/docs/current/tutorials/gsch2pcb/gsch2pcb-libs-20040110.tar.gz

Unfortunately it leads to an object not found page.
Would anyone have a copy of this library? 

This library is of particular interest to me as Bill
discusses the problems of correlating all the various
TO92 pin outs in gschem with PCB.

My next question is about the Symbol Attributes.

Lets say I wish to make a symbol for a BC550
transistor. As I would be using this particular device
a lot, I would like to make this symbol as correctly
as I can.

So, if I have a BC550 NPN GENERAL PURPOSE TRANSISTOR,
what are the preferred values to give:

Device=?
Description=?

My guess is that:

Device=NPN TRANSISTOR
Description= BC550 NPN GENERAL PURPOSE TRANSISTOR

Would this be correct or would you suggest some other
values?


My next problem is with the pins. I think what is most
important is that the pin numbers of the symbol pins
match the physical pin numbers of the particular
transistor when placed inside the PCB. Difficult with
TO92 as there are lots of em ;)

As you know... these small package transistors have
specific manufacturer numbered legs. In the case of my
BC550, I have a Leg #1 (Collector), Leg #2 (Base) and
Leg #3(Emitter).

Does it matter say if pinseq=1 is where transistor Leg
 #2 goes? Can we attach any Leg # to any pinseq#?

On the subject of pinnumber, what would a better
approach be? Should I use values of 1, 2 and 3? Or
would it be smarter to use values of E, B and C for my
transistor symbol?

On the subject of pintype for transistors, what should
I be using? pas? I am uncertain how open collector and
emmiter fit into the picture here. As I might wish to
one day run spice... I would really appreciate some
info on what values I should be setting for the E, B &
C legs on my transistors.

For pinlabel, would it be correct to say that I do not
need to include this attribute unless I am connecting
a particular transistor leg to another schematic
somewhere else? Or do I need to include this
attribute. If so.. what would I label them for the E,
B & C legs on my transistors?

Well guys... thank so much for your time going thru
this. Really appreciate it!

Regards

Mark















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