Can anyone explain what each wire on an audio output transformer (1k ohm center tapped to 8 ohms) is for?

Question

The transformer is a RadioShack mini Audio Output Transformer, and on the circuit i am using it in, all the wires on it lead to something except for the blue wire, and i cant figure out if this is a vital wire or not.

what exactly is the center tap for? BTW there are 5 wires.

Answer 1

If your circuit isn't asking you to use the center tap, then it isn't vital. However, you shouldn't connect it to anything -- it is there for other possible circuit configurations and if you do connect it (like to ground), it can mess up your circuit's operation.

The center tap on the 1k ohm side is used in different circuit configurations. You may have a single transistor/amplifier driving the transformer, so you'd have the output go to one lead and ground the other, leaving the center tap open. Another circuit could have two transistors/amplifiers (a push-pull system), so one amp could be connected to the top half, one amp connected to the bottom half, with the center tap grounded.

It's easy to put a center tap in when you make a transformer, so the product is useful for many more projects than just a regular two tap transformer. Since you can use the center-tapped transformer without connecting the center tap to anything, it can easily be used in those two tap transformer projects. That lets the manufacturer make more of one thing, which brings their costs down, and hopefully yours, too.

Answer 2

4 wires right ? 2 are primary[input] 2 are secondary similar to a power trfmr.test continuity with meter ,battery or soundusing lowest power test. part # 273--1380 has 1kohm center tapped primary and has 8ohm center tapped secondary. All vital