Hello Alfonso,

Auto junctions can be a good time saver as long as you understand where Protel will 
apply them.
I use them all the time.
Basically if a line touches a 'nodal point' of a pin - or other line then auto 
junction will place a junction dot.
I've never had it happen with a clean crossing, so you may be able to unclutter your 
diagrams a bit.

What looks like is happening with DXP is that 'end-to-end' lines are being 'auto 
cleaned up' so removing the junction that 'was' there - even if it was intentional. 
(not what you would expect to happen)

I personally avoid the 4-way junction, coming from a drafting background it's 
considered poor practice.
(star points usually end up at angles other than 90 deg anyway)
The 45 degree entry that you mention is preferred when you want to show circuit 
elements in line, as in a classic transistor biasing arrangement. The 'signal' line to 
the base being the one kept straight. (I remember transistors...they used them in 
'wirelesses' instead of valves didn't they?...  :) )

I always find it better when the PCB designer has the knowledge and background to 
produce the circuit diagram for the 'circuit designer' (EE) This lets the EE 
concentrate on engineering design issues rather than on the correct drafting of the 
circuit to whatever standard is appropriate and removes the 'over-the-wall' process 
that can occur.
The PCB designer also gains an in depth insight into the design with input into the 
CAD schematic based on downstream requirements. (Yes, I know that some places don't 
like to work that way.)
If only I could chip away at the traditional wall between mechanical engineering and 
electronic engineering some more..

regards,

Phil.



-----Original Message-----
From: Alfonso Baz [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, 15 October 2002 12:43 PM
To: Protel EDA Forum
Subject: Re: [PEDA] WARNING!!! Junctions at + points can disappear in
DXP


What gets me is why anybody would use auto junctions in the first place.

I'm guilty of using 4 way junctions, mainly because the circuit makes more
sense (an RC charging node for example) as opposed to staggering components.
If seeing the dots in a printout is a problem, make them bigger. (try faxing
someone an A3 schematic reduced to A4 and see if they can tell the
difference between a cross and a junction 8-)

Within 10 minutes of using P99SE's schematic capture I was on the hunt for a
way to turn it off.
I found that it was inconsistent in placing it's junctions, sometimes it
would place one where you wanted it and other times it wouldn't.

I was aware of the problems associated with 4 way junctions and at school
they told us to use 45 degree offsets on wires approaching a similar net
from opposing sides.... something like this

        |
___/______
         /
        |

and it cone be done quite easily in P99SE

Being a programmer myself, I have very little faith in software and even
less in the people that write it, as such I still worry about different nets
crossing at 90 degrees and resort to placing net labels on and near the
crossing.
Has this ever been known to be a problem? I hate cluttering up schematics,
they're complicated enough without having to worry about the PCB design as
well.

This brings me to another point. Shouldn't the circuit designer concentrate
on the circuit design and the PCB designer on the PCB design? and if so who
is responsible for the intermediate stage of converting the drawing from a
circuit design to a "wiring" schematic?... automated cad software?




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