Newsgroups: sci.electronics.misc
Subject: Re: Circuit Diagram Needed
References: <[email protected]>
"Dr. HackenSack"  writes:

> Hi group I would like some help if possible please.
> I wish to take a standard 3.5mm jack stereo lead from the "line out" of my
> PC sound card and then via a switching unit of some sort, reroute  the
> signal to any one of three outputs, hi fi, pc speakers, or headset, 1 in and
> select any one of 3 outs. I have been to Maplins but everything they have
> does it the other way round , 3 sources in and 1 out.

If those "3 sources in and 1 out" usnit you are referring to are 
just complete passive machnical switch units, then thy work 
without any problems in the opposite way: one input and three selectable 
output sources where signal can go one at time. 

> I have decided to try and make something up myself but i do not know the
> best and most efficient way to wire this all up.
> 
> Can anybody help me with a circuit or give me some advice as to where i
> might be able to buy a small unit
> 
> It doesnt matter whether its a rotary switch or push switches as long as i
> can easily select the output destination without having to rummage round the
> back of the PC and keep switching leads over

Simplest solution is to use this kind of existing ready product 
mentioned earlier and use it on the opposite direction. 
You can make one yourself if you want. 
Just keep the grounds of all connectors together. 
Switch the signal wires using 2 x 1 to 3 mechanical switch 
of your choise. Build the whole thing to a small metal case 
that is grounded to signal connector ground to keep the 
inteferences away from your circuit. This is how many 
commercial audio switchers are built.

-- 
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/