This link takes you to the TALKING HOUSE TRANSMITTER DIAGRAMS.
This link takes you to the TALKING HOUSE TRANSMITTER DIAGRAMS.
The document contains patent information and several diagrams of the transmitter. It is broken down into sections, block diagrams and schematics.
Page 10 details the ATU. I'm sure the transmitter may have undergone modifications along the way so consider these schematics as conceptual in nature. But, they appear to be fairly close if not the actual item.
The PDF file requires the free Adobe Acrobat Reader found at Adobe.com.
The link to the Free Patent site was found through a search on this website. Thanks Part15!!!

Spirit Award, Team MRAM
Fascinating stuff, and the ATU page even gives the values for the meter circuit.
