How to DIY Car Audio Isolator for RCA Interference?

If your car's screen has been switched to low-level RCA output but you're still experiencing severe interference, even after changing the isolation power supply, what should you do? You might consider DIYing a four-channel car audio isolator.

Here's what you'll need:

· 4 Siemens Pomona alloy transformers (600:2K4 ratio)

· 8 pure copper gold-plated RCA female connectors

· An aluminum alloy enclosure

· Perforated board

Drill 8 holes with an 11mm diameter in the perforated board. If you don't have a drill bit this large, you can start with smaller holes and manually enlarge them with a reamer.

The dimensions should fit perfectly.

For soldering, use silver-plated wire.

The appearance of the wires doesn't matter as long as it doesn't affect functionality.

Here is the finished product after soldering.

Once you add the top cover, you're done.

After testing, the common ground noise interference is completely eliminated. However, as it is an isolation transformer, the soundstage might be slightly narrowed and the bass slightly reduced. Otherwise, the performance is quite good.