utilizing this wall wart i found at work

[guitarhacknoise]

hey folks,
I found this power supply at my work, its from an old floppy drive.
let me describe then let me ask.
this is what the pin out looks like:

x                                 V
                            1o      o3
                            4o      o5
x                                 o2              
            - i edited to put the x's in to keep my
                                                                       "janktankerous" layout alligned. which is not working, sorry!

well, imagine that it is more circular and that the v is the notch to line the plug up with the female jack on the drive.
now, pin 1 =common
         pin 2 =ground
               3 = +5vdc@1.2a
               4 = -12vdc@0.2a
               5 =+12vdc@0.2a

first, what does the pin labled "common" do?
second, if i just want the +& - 12v. what do i do with pins 3 and 1?
want to use it to power my c.a. ring mod and other +/- circuits.
any advice would be appreciated.
-matthias :shock:

[Peter Snowberg]

Very cool.

+/- powered effects have three wires.... +, -, and ground (a.k.a. common).

In this case, I'll bet that "ground" connects to the outlet ground prong while common is the member of the low voltage outputs.

If you're using only the +&-12, just don't connect the +5 line to anything... or use it to power a BTL power amp chip.

[guitarhacknoise]

thanks peter,
but still, would i then use the common as the circuits ground ( i believe so) and if so do i not worry about pin 2 ground? or maybe use that in conjunction with the +5v  for  the power amp idea or whatever else? or could that common ground be used for both power applications? what about ground loops or am i way off?
-matthias

[Peter Snowberg]

I assume that "common" is the ground for the +12, +5, and -5 supplies, so I would wrap the "ground" connection up in heatshrink to avoid a ground loop. Leave pin 2 disconnected.

You can always use your meter to see if pin two connects to the AC plug.

[guitarhacknoise]

peter wrote:
                   You can always use your meter to see if pin two connects to the AC plug.
thanks a bunch, yes I could and yes it do!
what is this type of jack called?

[Peter Snowberg]

what is this type of jack called?

I'm going to guess by your picture that it's a DIN-5. Is it the same jack that MIDI uses?

[guitarhacknoise]

yeah, the same type o' jack.
I was thinking about scavanging the female end from the floppy drive, well actually it's a diskette, but seems like lately i've been running into cool stuff that has been robbed of this and that. I kinda want to keep the karma gods on my good side! (my dad is into building old cars and that's been his phillosophy) so if it aint broke don't steal it!
anyway, thanks, now i'll order a new one.

[Peter Snowberg]

No problem.

I think you might even be able to get those sockets at RadioShack if you're in a pinch.

I understand your Dad's phillosophy, but disk drives are on the way out forever and I'm under the impression that right now isn't fast enough. I have lots of old gear that I don't want to see tossed, but I have to face reality as a surplus collector too. I say any use you can get from old things is great! Recycle recycle recycle! :mrgreen: