[Elecraft] New Product request ...

[Dave G4AON]

Paul (and others)

A neat trick with audio spectrum analysis software running on a PC is to 
use a diode ring mixer, such as an SBL-1 or equivalent, feed a signal 
generator into the oscillator port and monitor the IF port on the sound 
card. Pi network attenuators on at least the IF port will reduce 
spurious signals which could result from the mixer not being properly 
terminated with 50 Ohms. While exact details are perhaps a bit much for 
this list, it's neither complex nor expensive to produce and another 
useful item for your shack drawer.

To give a broad resistive termination for feeding a signal to such 
devices, I use Wes Haywards resistive tap from the June 2001 QST (Simple 
RF Power Measurement), this is available from the ARRL members part of 
their web site. For a signal generator I use an old Marconi 2018.

The free software "Spectrum Laboratory" from DL4YHF 
(http://freenet-homepage.de/dl4yhf/spectra1.html), which also includes a 
two tone test generator, and can be configured for an orange graticule 
and green trace to look like a proper spectrum analyser.

All good fun for less than $10.

73 Dave, G4AON