[net.micro] Search for Jumpers ?

clark.wbst@PARC-MAXC.ARPA (09/30/83)

Someplace I have seen... does anybody know where I can get this, or something like it?

... A short jumper to go between wire-wrap pins.  A short (1/4"?) cylinder
slid over the pin, and the pin went right through, out the top.  A wire
went to another sleeve for the other pin.  The result was that the whole
deal did not stick up higher than the top of the wire-wrap pin.

What I need to connect is the NPG continuity jumper on a UniBus backplane.
To get from one pin to the other you go up 0.125" and left 0.125", so it is
0.177".  I can't imagine anyone making a little jumper with that fixed
distance, but...

I want to be able to remove and add it very easily, without playing with
wire-wrap wire, yet do not want something kludgy like a piece of bent
solid wire, since it will be done by non-hardware types. 

Any help would be greatly appreciated !

--Ray Clark

   Clark.wbst
   Clark.wbst@parc-maxc
   EEvax.clark.wbst@parc-maxc
   allegra!rocksvax!clark
   depending on where you are....

RBENTLEY.ES@PARC-MAXC.ARPA (10/01/83)

I am the tool coordinator for PSD and part of the Xerox Multinational
Tool Committee. currently we use jumpers for backplanes for
troubleshooting but could just as well be used for your purposes.  They
may not be as short as you require but you can check them out anyway.
They are orderable through National Distribution Center in Compton
California.  they are as follows;

600T1046           Jumper Wire 3"
600T1047           Jumper Wire 6.5"
600T1048           Jumper Wire 10"
600T1049           Jumper Wire 27"

A local contact in Webster would be Bob Metz. This jumper works so well
and is so easy to use that the it is used quite a lot.

Hope it helps you.

Roy Bentley

dmmartindale@watcgl.UUCP (Dave Martindale) (10/11/83)

My favourite way to put in a temporary NPG jumper while a Unibus DMA card
is removed is to take a blank Flip-Chip card (DEC used to sell these,
maybe they still do) and wire the foil at positions A1 and B1 together.
Then you plug this into the backplane in the row just above the
grant continuity card and you have provided continuity for NPG as well.

Even better, I believe that one of the DEC-lookalike vendors (Able?)
makes a card which plugs into rows C and D, providing the function of both
the ordinary grant continuity card plus the NPG card described above.
Also, it is the length of a normal card and has handles on it
so you can insert and remove it without mangling your knuckles!
I think this would be the way to go for non-technical people; it makes it
much more difficult to short together the wrong pins, and it also eliminates
the danger of putting the continuity card in upside-down or in the wrong
row.  (I'm sure I'm not the only one who's done this...)

	Dave Martindale
	allegra!watcgl!dmmartindale
	decvax!watmath!dmmartindale

twt@uicsl.UUCP (10/18/83)

#R:watcgl:-94400:uicsl:7000028:000:220
uicsl!twt    Oct 17 20:18:00 1983

	DEC now uses a "grant card" like the one mentioned above in the 11/24's
and 11/730's. The DEC part number on the handle is G7270. I don't know if you
can get it from DEC or not.

	Tom Todd
	...pur-ee!uiucdcs!uicsl!twt

smh@mit-eddie.UUCP (Steven M. Haflich) (10/18/83)

I cannot recommend the following kludge without reservations, but
have used it in years past when expedient without difficulty:

A Unibus NPG jumper can be constructed from a miniature SPST slide
switch wire wrapped to the appropriate backplane pins.  The leads
must be kept short, of course, and the biggest difficulty is
affixing the switch and wires *securely* so they cannot become
caught on anything.  This latter is partcularly important if your
backplane s mounted on slides!

Steve Haflich, MIT Experimental Music Studio

hoffman@pitt.UUCP (Bob Hoffman) (10/27/83)

DEC now has a dual-width, extended length "double-grant"
continuity card.  It's part number G7273 and it plugs into
the C and D connectors of a hex SPC slot.  I had never seen one
until last week when our new 11/24 was delivered.  It's certainly
an improvement over the old G727 cards.

	---Bob Hoffman, U. of Pitt Computer Science.