Audio Troubleshooting Still

The results of yesterday’s ground problem correction were good. Everything in the system works except for the channels that go through the iso amp. I took a break from troubleshooting to install the aft 12v SAE jack, and run a few cabin wires. I installed the dimmer for the instrument panel flood lights. The dimmer came from All Electronics, but is also available from Aircraft Spruce for about four times the price.

Pulse Wave Modulation Dimmer

Pulse Wave Modulation Dimmer


The dimmer has a sub-optimal wire connection method. The back of the dimmer is potted with some white rubbery stuff, so I removed the potting in the corner where the green terminal block was attached. I cut the leads off from the block, which liberated the block itself, then used the soldering iron and needle nose pliers to remove the remainder of the leads.
Dimmer ready for new wires

Dimmer ready for new wires


Then I soldered tefzel wires into the holes where the terminal block used to be. One wire comes in from the fuse (which is on the battery bus), then one goes to the central grounding point. The other two go to the front cabin flood light. The light in the back is controlled by a switch near the right rear passenger headsets, and it is on or off only, no dimmer.
The front light is selectable as red or white, with the switch that is right next to the light. I took the output from the dimmer to the center post of the switch, then took the red input from one end post and the white input from the other post.

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Hours Logged This Session: 10.2
Total Hours: 1883.75