| MadSci Network: Engineering |
What you're asking about appears to be an early form of "companding" (compression and expanding), a technique often used these days in digital communications systems to compress the dynamic range of a voice signal and better utilize the available dynamic range of the communications channel. The phone company, for example, uses something called "mu-law" (usually written with the Greek letter mu) companding as it does a digital to analog conversion of your analog voice signal to digitized data.
All of which is interesting, but tangential to your question. Unfortunately, I can't give you any definitive information about how Taylor modulation works, but did find a lead to a publication called Electric Radio Magazine which is dedicated to discussion of antique (i.e., vacuum tube) radio equipment, with a particular focus on amateur radio. The home page includes a pointer to a downloadable index file. An online version of the index provides several references to Taylor modulation. You might also try the internet newsgroup group rec.radio.amateur for contact with kindred souls. There is a subgroup rec.radio.amateur.boatanchor dedicated to discussion of vintage radios, as well. The rec.radio.amateur.boatanchor FAQ contains a wealth of information on additional sources of information and parts and equipment supply related to vintage radio. 73 Steve Czarnecki
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