On Sat, 01 Aug 2015 13:32:53 -0700, jurb6006 wrote:

"It is very instructive when using a THD analyser to view the residual
signal on a scope - so you know what it consists of. "

I assume that is what is at the "monitor" terminals. Is that correct ?
Iff thsat is what it is I would like to have a scope connected there, or
later when I get one, a spectrum analyzer maybe ?

The 339A manual is on the BAMA site at edebris.com