RF Signal Degrader - Projects - Beneath the Waves

RF Signal Degrader

The RF Signal Degrader is a simple device that I built for my friend Raw Garbage to use as part of one of his art pieces. It was a television with stand (see Stencil Art by Raw Garbage for the finished product), and he wanted to simulate poor television reception for the feed from a DVD player (this was after the analogue television cutoff in the US, and he also wanted to specifically choose the content).

Originally I had planned on just using The Less-Than-Ideal Transformer inline, but this actually improved the signal versus simply connecting the two coax leads (maybe due to a ground loop?), although of course it was still worse than using an off-the-shelf RF cable.

I quickly modified the design to incorporate a potentiometer wired up as a variable voltage divider - that is, it became a "volume control" for the amount of RF signal passing through the circuit. I left the transformer in with a switch to add it to or remove it from the circuit (with the "out of circuit" mode being "more noisy") and also because its weight made the box feel much more impressive.

Raw Garbage added a nice paint job, and it fit right in with the rest of the piece.

The box, knob, switch, and RF connectors were all off-the-shelf parts from Radio Shack, although their continued winnowing-down of their electronics component sections nationwide means they may no longer be available unless buying online. The potentiometer was from my box of parts, and therefore probably purchased from Jameco or Mouser Electronics.

The RF Signal Degrader

The Unpainted Box

As Painted by Raw Garbage

Schematic

Date Shot: 2009-03-04
Camera Body: HTC Dream / T-Mobile G1
Lens: Unknown
Filters: None
Date Processed: 2009-03-22
Version: 1.0