How to make a simple freq. analyzer with a old oscilloscope?

I have an old 20Mhz oscilloscope.
is it possible to make a simple freq. analyzer with a old oscilloscope?

Oscilloscope can be used only as a display unit. Basically for frequency analysis you need VCO, time-base generator and amplitude detector. Time-base generator signal should be used for X deflection and detector signal for Y deflection on oscilloscope. Usually a XY display mode is used for oscilloscope.

See S53MV spectrum analyzer in VHF communications or the web. It uses oscilloscope as a display for 100kHz to 1.8GHz spectrum analyzer. It's not simple though...

For the experimental or know how purposes, it is good to make such equipment. But my experience and logic says, always buy basics or advanced equipments (for your measuerment needs), even if you are able to build them. Because these are build by professionals and have very costly reference tools to calibrate them. So, for any professional work one should do that. For the cost issues, Yes, these are comparitivly costly. But one can use some organisation equipments on their site.

Regards

Here is Matjaz Vidmars page:
http://lea.hamradio.si/~s53mv/
he has the same articles published in VHF Communications there and much more.

I saw a long time ago - at university lab - a simple circuit containning just a scopemetter, a ramp-generator, and a VCO modulating circuit.

The problem was the small frequency bandwidth scanned, but maybe using other VCO circuit it could reach greater bandwidth.

It worked very well.


+++

http://www.holmea.demon.co.uk/SpecAnHtml/SpecAn.htm