Steve,
I'll try this again. I went to answer this AM and my computer froze.
We use an SMT adhesive or something that is more or less made for this type
of situation, like Dymax 911, among others. In every case we only use
materials that we have tested for corrosion by chloride ion test, copper
mirror, SIR and electromigration. The latter is done with the solder mask.
I don't have the background to comment on your routing question.
I was going to have a snappy comment about you "working" on a Saturday, but
that would be a little ridiculous, seeing as when I am answering this.
regards,
Bev Christian
Nortel Networks
613-967-5407
> -----Original Message-----
> From: Stephen R. Gregory [SMTP:[log in to unmask]]
> Sent: Saturday, February 27, 1999 3:16 PM
> To: [log in to unmask]
> Subject: [TN] Assy: Jumper wires, Bifilar wire to be precise...
>
> Hey Ya'll...
>
> I'm at work today (big suprise there I'll bet...), working on doing
> the
> visual aids for that rework job I was asking about a week or so ago.
>
> I just ran into a little suprise that I didn't notice when I was
> first
> doing the quote. I've got 16 of the 85 jumper wires that are done with
> Bifilar
> wire, and they are done in pairs. One jump will be with the green wire
> from a
> pin on a IC to another pin on another IC, and the jump with the red wire
> will
> go from a pin on the same IC that the green wire originated from to a
> totally
> different IC than where the green wire terminated at. For instance, here's
> one
> step:
>
> Green: From U21 pin 19 to U49 pin 2
> Red: From U21 pin 20 to U133 pin 2
>
> Now I do know that both wires need to be as close to the same length
> as
> possible and any excess length coiled up or zig-zagged on the way to it
> destination, that's because in each of these Bifilar jumps the signals are
> paired or matched to take the same time to travel, but should you route
> the
> jumpers straight as a crow flies, or make them esthetically pleasing
> following
> a pattern like the traces in a board are routed? What about securing them
> down? Any special way I should tack them down to the board, or anything I
> should avoid using?
>
> Boy, you live and learn when doing quotes...THAT's for sure!
>
> -Steve Gregory-
>
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