[Elecraft] OT: Amplifier's close in IMD product test

[N2EY at aol.com]

In a message dated 2/14/06 6:54:20 PM Eastern Standard Time, 
kg0wx at hotmail.com writes:


> Does anyone know how to test an amplifier, or for that matter a 
> transceiver, 
> for close
> in IMD products? What kind of equipment is needed?
> 

That's what a "two-tone" test is for. 

The RUT (Rig Under Test) is set up for SSB operation, and two pure sinewave 
nonharmonically related audio tones in the audio passband are fed into it. 
Output is examined with a spectrum analyzer.

A perfect rig would emit two carriers and nothing else. Imperfections 
(odd-order IMD products) show up as carriers besides the two desired ones. 

73 de Jim, N2EY