4 Wire Turntable Output

[Frank Myers]

I have a classic Bang and Olufsen Beogram tangental arm turntable. The
five pin DIN plug has completely broken off while in storage and I
need to resolder it.

Unfortunately, I am unfamilliar with the wiring convention for
equipment of this type. Can someone please help?

There are four insulated wires, red, blue, brown and yellow, plus the
earth shield.

All wires carry an audio signal relative to earth. I looked inside an
they are all connected to the PCB.

Why are there FOUR live wires when only two are required for stereo?

How can I determine which two go the the phono input of my amp, and/or
what the remaining two wires are for?

Frank Myers

 

[Frank Myers]

On Tue, 15 Feb 2011 23:28:59 GMT, [email protected] (Frank
Myers) wrote:

Please ignore my previous questions. I found this on the B&O forum
that seems to expalin it all.

http://forum.beoworld.org/forums/t/37710.aspx

Frank

 

[Sjouke Burry]

I have a classic Bang and Olufsen Beogram tangental arm turntable. The
five pin DIN plug has completely broken off while in storage and I
need to resolder it.

Unfortunately, I am unfamilliar with the wiring convention for
equipment of this type. Can someone please help?

There are four insulated wires, red, blue, brown and yellow, plus the
earth shield.

All wires carry an audio signal relative to earth. I looked inside an
they are all connected to the PCB.

Why are there FOUR live wires when only two are required for stereo?

How can I determine which two go the the phono input of my amp, and/or
what the remaining two wires are for?

Frank Myers

Two pairs of wires connected to two pickup coils.
Use an ohmmeter to identfy the pairs, there should be
something like 100 to 1000 ohms resistance for each coil
and the resistances should be equal for both coils.
Each coil is one of the stereo channels.
Th fifth wire should be shield, and show about 0 ohms
between wire and the metal of the tone arm and pickup element.
If there is a pre-amplifier inside, only tracing the wires
will show what they did.
If so, check the circuit board for markings, there might be
a balanced two wire output for each channel.
My B&O is of the simpler type, and without pre-amplifier.
I am not going to open it up however.