Spectrum Analyzer on the Cheap

Provided you have an NTSC-compatible TV you can build yourself a really inexpensive spectrum analyzer. From there you just need one trivial piece of hardware to complete this build. [Bruce Land] has come up with a spectrum analyzer that shouldn’t cost any more than $5, if that’s what’s been keeping you from adding this tool to your workbench!

The spectrum analyzer is based on a PIC32 microcontroller which was previously proven in his Oscilloscope project. [Bruce] has managed to squeeze quite a bit out of this robust chip; the spectrum analyzer has 450 kHz bandwidth and runs a 256 Hz TV display and can output over 30 updates per second. The microcontroller runs the Fast Fourier Transform (FFT) to do calculations, with great results.

[Bruce] notes that the project was based on TV framework from another project, and that the FFT was added on top of that. Be sure to check out the source code on the project site if you’ve been on the hunt for an inexpensive spectrum analyzer, and if you need something with more processing power but only slightly more money, check out the FFT that runs on the Raspberry Pi’s GPU.

Build an analog TV station


With the transition to digital TV, the FCC has abandoned the old analog format. Luckily, you can take advantage of this and set up your own analog TV station. The FCC has a tool on their site to see what channels are open in your area to broadcast in. To broadcast, you need a TV transmitter, but cheap short-range models can be found on eBay or made at home [pdf]. Once you have a transmitter, you can pump in a video source, either your own content or videos from youtube. One group, OMGimontv is showcasing popular youtube clips on channel 14 in New York. On their site, users can vote for what clips they want to see. Although this isn’t as simple as making a radio station, it still has a lot of potential.

[via BoingBoing]