DEC Computer Lab for sale

[Vincent Slyngstad]

On 5/30/2021 1:02 PM, Mike Stein wrote:
> What's the length and the diameters at each end of the pin? I've got 
> some cables for Burroughs patch panels that might be useful.

The pin diameter at the rounded tip is .093", a standard pin diameter. 
It flares to 0.102" or so, over about 0.34" of length.  The overall pin 
length (including the insulation crimp/strain relief) is about 0.65".

Also measured some patch cords (pin tip to pin tip):
Brown is 2.75".
Red is 4.75".
Orange is 6.75".
Yellow is 8.75".
Green is 16.5".
Subtract about an inch and a quarter for the length of the visible wire.

There was also blue, though I don't have one to measure.  My notes 
remind me that the blue looks about an inch or so longer than green, 
based on the cover photo of the manual. At that length it will 
comfortably reach across the device, whereas the green is just a little 
short for that.

Found in my old notes:
The DEC 12-03498 was a #41675 taper pin.
Similar AMP taper pins:
42107 "88" series will fit.
42279 is similar, though obsolete.

My old notes also suggest higher quantities for the patch cords; 100 of 
them all together:
B 20
R 30
O 25
Y 20
G 10
B  2

	Vince

> On Sun, May 30, 2021 at 3:40 PM Vincent Slyngstad via cctalk 
> <cctalk at classiccmp.org <mailto:cctalk at classiccmp.org>> wrote:
> 
>     On 5/30/2021 10:54 AM, Ethan Dicks wrote:
>      > On Sun, May 30, 2021 at 11:42 AM Vincent Slyngstad via cctalk
>      > <cctalk at classiccmp.org <mailto:cctalk at classiccmp.org>> wrote:
>      >> https://so-much-stuff.com/pdp8/computerlab/computerlab.php
>     <https://so-much-stuff.com/pdp8/computerlab/computerlab.php>
>      >> The photos get a little bigger if you click them.  Those bits of
>     stamped
>      >> brass or whatever they are made of were probably pennies each.
>      >
>      > I've thought about what it might take to manufacture a pair of steel
>      > rollers that could stamp those out but I haven't gotten very far with
>      > it.  Same idea for the backplane bus strip DEC used to sell on the
>      > roll.
>      >
>      > Depending on level of detail, either a small CNC or possibly a wire
>      > EDM could make the dies.
> 
>     I thought about machining a ram to deform an existing modern pin (or
>     even just tubing) to create the taper.
> 
>     I also tried to cast some out of solder, but they had bubbles and
>     were a
>     little too soft (tin-lead solder).  Also, with a solder connection you
>     really need a good strain relief.  At some point it's too much work for
>     what you're accomplishing (and still not very authentic).
> 
>              Vince
>