Mini-DIN Audio Input Connector for a SparcStation-1

[William J Carpenter]

In article <1484 at brazos.Rice.edu> jipping at cs.hope.edu (Mike Jipping) writes:

> Has anyone successfully wired a microphone-to-audio-input adapter for the
> SparcStation-1?  The 4.0.3 Release Notes manual has the pins required for
> a do-it-yourself version of this adapter...
> ...but where does one find the Mini-DIN plug in the first place?  I can't

What I did (after looking around in the right places for the right thing
and coming up dry) was to look in a place not expected to be sophisticated
enough.  In other words, a regular old cater-to-the-masses computer store.

Turns out that some Apple equipment (I forget which) uses these 8pin
mini-DINs (note: *not* regular size 8pin DIN available at Radio Shack and
everywhere else).  So, I just bought some kind of printer cable or
something that had a connector on both ends, cut it in half and was ready
to solder up two Sparcstation audio I/O cables (no, sorry, you can't have
one of mine :-).

Although the Sparcstation docs tell you which signals go on which pins,
they don't tell you which pins are which on the mini-DIN.  Of the two
cables I made, one has really bad hum (since I skipped the shielding
stuff) but works in both directions; the other works only for
microphone/line input, but is clear of hum (I figure a bad solder
connection or something).  Since I was only interested in input anyhow, I
haven't bothered to screw around with them.

We recorded a bunch of stuff off a CD player this way until we got bored
with using up all that disk space (8k/sec) and went back to work.

Here's what I surmised:

================================================================
Here is the pinout for the 8-pin mini-DIN connector on the back of a
SPARCstation 1.  BTW, "8-pin mini-DIN" is not the same thing as "8-pin
DIN", although I believe the pinouts are the same.

  Cable connector                 Pizzabox connector

        v                                 v

    6   8   7                         7   8   6

    1   2   3                         3   2   1

      4   5                             5   4


The "v" is the key on the top of the connector.  The left picture is
looking into the connector on the end of a cable, and the right picture is
looking into the connector on the back of the box.  This is actually the
pinout for 8-pin DIN.  I am sure it is right for the four wires we use on
8-pin mini-DIN, since I made a cable and it works.  The others could be
off since the 8-pin DIN has a different physical placement of the pins and
I had to guess which corresponded to which.

Here is the excerpt from p 89 in the SPARCstation release notes:

   Mini-DIN 8-pin end        Phone jack

         Pin 3           Microphone Tip (center connection)
         Pin 6           Microphone Ring (also connect to shield)
         Pin 7           Speaker Ring (sleeve)
         Pin 8           Speaker Tip (center connections -- not stereo)

The jazz about connecting pin 6 to shield is important to keep out
hum.

   Bill Carpenter         att!ho5cad!wjc  or  attmail!bill