1. The original soundcard used must have been capable of driving speakers direct
2 Extra low source buffering had to be incorperated to give lower output impedance.
3  Extra uses were sought for the interface with the soundcard, 3 phase audio generator, multi-curve tracer. All using adaptable software. A very useful research tool worth incorperating.

The availability of some 10nF ,1% capacitors made this capacitance box achievable. With parallel and series combinations it covers 1nF to 100nF . This has been all that is necessary to check the LMS bridge. Inductance of course has the oposite quadrature phase. As in the origal design all impedance measurements are made traceable to resistance measurements made on a 4 terminal DVM.  Link to present state of LMS bridge write-up(7zip archive)