491

The Tektronix 491 is a spectrum analyzer introduced in August 1966.

Due to severe performance limitations, it was replaced by the completely redesigned 492.

Manuals

• http://www.ko4bb.com/manuals/index.php?dir=Tektronix/Tektronix_-_491_Spectrum_Analyzer

Links

• http://www.radiomuseum.org/r/tektronix_spectrum_analyzer_491.html