Circuit Lake

Electronic Project and Circuit Collection

Portable Spectrum Analyzer

01/17/2010 Category: Ham Radio, Measurement, PIC, Tools

If you have ever attempted to do any projects that involved UHF/VHF frequencies, what is immediately apparent is that your normal test equipment is very inadequate. Standard TV signal space, for example, runs from 50 to 878 MHz. The cost of acquiring test equipment that operate at those frequencies, like signal generators or an oscilloscope, is very steep. The primary tool for working at RF frequencies is a spectrum analyzer (SA). Once again, the price of these devices are out of sight for the typical hobbyist.

Spectrum-Analyzer-Front


This project attempts to solve the problem by utilizing some newly available digital chips and dsP technology (dsPIC33FJ256GP710)to provide a flexible spectrum analyzer that operates from 50 to 950 Mhz. The design employs state of the art high speed analog to digital conversion (ADC), digital down conversion (DDC), numerical controlled oscillators (NCO), finite impulse response filters (FIR), and fast fourier transform (FFT) technology, The beauty of the approach is that is relatively cheap ($200 parts), very repeatable because it is digital, and is self contained & compact. Project designed by Neal Martini.

Portable Spectrum Analyzer
Download Project Documentation (zip)
circuitcellar.com