Do I need to connect the metal horseshoe with RCA plugs for my turntable to work?

remove rca plugs from speaker wires and wire the speakers to speaker connections on the back of receiver. The receiver may already have a phono input for a turntable.

If the receiver doesn't have a Phono input, you will need to turn on the Pre-Amp and connect the turntable to another input. Connect the Red and White RCA cables to the left and right audio inputs on the receiver. Connect the RCA cables to the audio outputs on the back of the turntable

If your receiver only has a mini plug in you will need a phono pre amp that takes phono in and pit line level out. Then you can use an rca to mini adapter to plug into your reciever.

Fortunately for you somebody on a forum did rebuild this turntable to working order, without the rest of the system. This is what they wrote:
"A 2x10 V 10Watt transformer to the wires ( white connected to the center tap ) and the TT came to life. The TT doesn't contain a preamp but the cartridge is connected to the small PCB covered by a metal shield ( you can put RCA connectors in the back like I did )."

Connect the RCA phono plug wires usually red and white wires with plugs to a receiver or amplifier in the back of it to phono in. New receivers will not work unless you have a phono preamp. Best to buy a vintage stereo receiver or amplifier with the correct connections. Make sure you connect the ground wire which is usually a small black wire coming from the turntable to an receiver or amplifier. Turn the stereo receiver on phono. Connect it to any screw attached to metal on back or look for a ground screw. If you do not attach it it will hum.
http://www.hardwaresecrets.com/imageview.php?image=357

plug the RCA phono plugs from tuntable into preamp in & then plug the preamp out to an open RCA plug on your amp or receiver like tape 1 or CD or aux.

Use a flat screwdriver to pry it off.

hi,
Here is the wiring of the turntable RCA plug ( RCA wire will have 4 connections like red and its outer wire then White and its outer wire.). connect these as follows.

For right channel

Red wire from the turntable to the red center wire of the RCA plug

Green wire from the turntable to the outer wire with red wire of the RCA plug

For left channel

White wire from the turntable to the white center wire of the RCA plug

Blue wire from the turntable to the outer wire with White wire of the RCA plug
OK

Hello,
You don't need the original ground wire for Technics SL-BD20D turntable,
any plain cable can be used for this purpose...
you should connect turntable to your pre amp,should be a "phone" input at the back...
here are some suggestions for grounding....
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Plug in a surge protector to the outlet, and then plug all the components into that surge protector

Connect a ground plug to the surge protector and then plug the ground plug into the main outlet. A ground plug is available at any hardware store, and turns a three prong connection into a two prong. Ground plugs help eliminate 60 cycle hum.

Connect the ground wire from your turntable to the ground wire connection on the receiver. If this doesn't work, looking on the back there should be a grounding point,

Unplug your receiver.. Split a wire and attach one of the splits to the receiver where you will see the text, "ground" or something similar. Attach the other end to something metal such as a pipe that goes into the ground. Secure with electrical tape. Plug in.
connect the ground wire to a screw on the electrical outlet.

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Hope this helps!

The USB turntable is likely a USB data connection and not a USB audio connection, so you will need to take the audio output from your Mac G4 to your Sony Mini Hi Fi...

You will likely need a stereo mini-plug (3.5mm or 1/8-inch) to stereo RCA plug cable (red and white RCA plugs). This is often referred to as a "stereo Y-cable."