RE: differential probes

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

Hi Jimmy,

Cool!

R13 to R11  and R14 to R12 seems too "thin".

R12 to the MOV seems to have a small place where the traces are thin too.

The ground pad of TVS11 does not seem to have a via to the ground plane.

The traces for LED31 and R31 seem thin.

I don't think the ground for the MOV on R22 is right.

We may be able to just put the fuses between the PC board and the actual 
banana jack connectors on the plastic case.

I am thinking about using F211-ND fuses from digi-key.  They are non-stock 
but they have 480 of them.  Pigtail fuses would eliminate fuse holders but 
the fuses could also go in insulated in-line fuse holders too.  So 
basically, I don't think we should worry with putting the fuses on the 
board.  They are probably better off somewhere between the board and the jacks.

Thanks a bunch for doing all this!!!    It should be really cool!!

Cheers,

         Terry

At 04:44 PM 7/17/2003 -0700, you wrote:
>Hi Terry,
>
>I fixed the changes you mentioned, but probably
>created just as many new ones.
>
>I put banana jacks for the input, and BNC for the
>output, is that what you wanted? It was tough to get
>enough clearance, so Ill just have to chop the boards
>up. I think The MOVs have to go on the back, I hope
>thats OK. Here are the new files
>
>www.hot-streamer-dot-com/chunkyboy86/diffprb3.jpg
>www.hot-streamer-dot-com/chunkyboy86/diffprb4.jpg
>www.hot-streamer-dot-com/chunkyboy86/diffprb2.pcb
>
>If I can fix the rest of the problems by 11:00 AM
>tomorrow, then I will order them tomorrow.
>
>--- Tesla list <tesla-at-pupman-dot-com> wrote:
> > Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>
> >
> > Hi Jimmy,
> >
> > At 11:36 AM 7/16/2003 -0700, you wrote:
> > >Hi,
> > >
> > >I used expresspcb for the layout. There are some
> > pictures of it here:
> >
> ><http://www.hotstreamer-dot-com/chunkyboy86/diffprb.jpg>www.hotstreamer-dot-com/c 
> hunkyboy86/diffprb.jpg
> > >www.hotstreamer-dot-com/chunkyboy86/diffprb2.jpg
> > >
> > >You can also download the software, and change the
> > layout yourself.
> >
> ><http://www.hotstreamer-dot-com/chunkyboy86/diffprb.pcb>www.hotstreamer-dot-com/c 
> hunkyboy86/diffprb.pcb
> >
> > >
> > >
> > >I haven't fixed any of the problems Terry pointed
> > out yet. I am waiting
> > >for the new design.
> >
> > I think you should go ahead and make the changes and
> > get the boards.  I
> > have thought about the spark gaps and all, but I
> > think the MOV design is
> > the way to go.  The fuses could be 1/4 x 1-1/4 low
> > current pig tail
> > fuses.  That would be as good as anything.
> >
> > We simply are not going to be able to protect
> > against "everything" but we
> > can do a lot and this design:
> >
> > http://hot-streamer-dot-com/temp/DiffProbe-5p.gif
> >
> > does just about all that can reasonably be done.  So
> > I think it is time to
> > go for it!  Things may change, but we need the
> > boards to do actual
> > testing.  We are not going to be able to "think
> > through" the remaining
> > unknowns.  We actually have to try it.
> >
> > I don't know how much having the boards made costs?
> > This would probably be
> > a "prototype" and a final design turn would be
> > needed.  I don't know if you
> > wanted to spend money on an totally unproven design?
> >  I can certainly help
> > with the cost of these unknown boards if you want.
> >
> > Cheers,
> >
> >          Terry
> >
> >
>
>
>=====
>Jimmy
>
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