Due to a recent flurry of interest/argument on MAPUG recently, here are the pinouts of the Meade Lx200 DEC cable. Also shown are images of the RJ45 ends and how they are pinned. I have successfully made cables this way, they work great.
Step one: forget what the cable is called! Everyone has their own terms for an Ethernet cable, a 'crossover' cable, a 'straight-through' cable, a 'rollover' cable, or a 'patch' cable, etc. While I am sure that somewhere there is a spec for exactly how these are pinned out, no one is using that standard in everyday language. I work in the computer field and just about everyone means something different when they use these terms (and they all 'know' they are right)! Use the pinouts when describing the cables and you will always be correct, no matter what the cable is called.
The DEC cable can be made yourself from CAT5 Ethernet cable or 8-wire flat phone-style cable using industry standard RJ45 ends. It can also be ordered from Digikey using the part numbers listed at the bottom of the page.
1-8, 2-7, 3-6, 4-5, 5-4, 6-3, 7-2, 8-1
End-to-end the view is thus:
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1-8
2-7 3-6 4-5 5-4 6-3 7-2 8-1 |
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Note that the pin #'s are opposite each other but the wire colors line up.
If you prefer a side-by-side comparison:
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12345678
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12345678
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Note that in this comparison, the pins match each other from left to right,
but now the colors are reversed.
RJ45 Pinouts
Here is an image of the RJ45 end and how the pinouts are laid
out (the cable would come out the bottom of the image, the tab is on the back):
Here is an image from the 'end-view' (cable coming out the back of the
image, away from you):
Part numbers courtesy of MAPUGer Roy Gillard - Thanks Roy!
These are black coil-cord similar to the original. Also available in white or silver. See online catalog (page 86) for details at www.digikey.com
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Part Number
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Length
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Price (1/11/01)
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H1882-05C-ND
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5'
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$7.52
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H1882-07C-ND
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7'
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$7.28 *
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H1882-10C-ND
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10'
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$9.16
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H1882-14C-ND
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14'
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$9.88
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(* the lower price for the 7' compared to the 5' reflects
a different vendor from within Digikey and is the correct price as of the
date posted)
more to come
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Copyright
2001 © Anthony J. Kroes.
Last updated 03/28/01
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