On Sat, 28 Mar 2009 06:17:02 -0700 (PDT), DManzaluni
wrote:

There used to be a really cool tuner made by Sequerra which I saw in
the 1970s which had this amazing feature on a built-in scope.

The magic buzzword is "panadapter". Search Google for lots of hits.
For fairly narrowband applications, it's sometimes called a
"waterfall" display.

The feature is found on some AOR scanners. All the SDR (software
defined radio) tuners have panadapters in software. For example:
http://www.rfspace.com/SDR-IQ.html (see photos)
Any synthesized receiver that covers the FM band can have this
feature, but you need direct access to the frequency control and IF
output. The panadapter sweeps the frequency range, and displays the
detected signal strength versus frequency on an x-y display.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558