[Elecraft] Barrel plug specs for K1 power

[Tom Hammond NØSS]

Lloyd:

>I'd appreciate some help in finding the plug to fit
>the power input jack on my impending K1, and advice on
>wiring it up. I'll probably be using a bench power
>supply with binding posts, for the other end. Thanks!

 From the reflector, a while back:

Rod Cerkoney, N0RC, wrote:
>The plug is 5.0/2.1mm OD/ID respectively. RS has them, but I don't
>have the P/N. In store packages have size marked on them. The part
>Elecraft supplies is from Switchcraft and is available from Digikey
>part number: SC-1052-ND (I think the Switchcraft item is of superior
>quality).
>
>The Connector in the radio (probably Switchcraft) is Digikey item:
>SC1155-ND
>
>Digikey online page for these items is:
>
>     http://info.digikey.com/T013/V5/177.pdf

More info:

    Switchcraft #S760, Mouser part #502-S-760

    Technical specs:  ID  .080" (2.03mm), assume 2.1mm
                      OD  .218" (5.5mm) See NOTE below
           Barrel Length  .375" (9.52mm)

Note: Switchcraft does not list a 5.1mm (0.20") diameter
       barrel coaxial power connector. It appears that ALL
       of their coaxial pwr connectors are 5.5mm (0.218")
       in diameter.

       I used a caliper to confirm the outside diameter of
       the barrel of the plug I'd received from Elecraft.
       0.218" (5.5mm) on the button.

For more info on this Switchcraft connector, go to:

    http://www.switchcraft.com/

and search for "S760". The plug dimension specs are at the bottom of this 
page, and if you click on selection #2 (760/S760) from the list at the top 
of the page, you can download a single-page PDF which shows to detailed 
engineering drawing of the plug, with references which will match to the 
specs on the page noted above.

I believe this to be the power plug which we are using on our K2s and K1s. 
They ARE better quality than the plugs available from R/S, if for no other 
reason that the fact that the center cunductor of the Switchcraft plugs is 
slightly recessed within the insulator, thus making it more difficult to 
accidently short the positive lead to ground.

The apparent R/S equivalent (at least with regard to dimensions, NOT 
quality) is their 274-1569 (5.5 x 2.1 mm).

The apparent DigiKey part #'s are:

      Plug SC-1052-ND (as Ron has stated)
    Socket SC-1153-ND (the SC-1155-ND is SMT)

NOTE that the 1998 DigiKey catalog from which I got this info had the 
Switchcraft part #'s for the plug and jack SWITCHED. However the DigiKey 
web site (www.digikey.com) had everything listed correctly.

Users are urged to RETAIN this information for the future when you will 
surely need it. And WILL eventually need it... almost guaranteed!

Thanks Ron,

Tom Hammond   N0SS