I thought this information might be helpful to some CRPF members with respect to repairing / restoring a Northern Electric Princess Telephone set. The information I'm posting, has to do with the wiring of the Northern Electric NE-1702-B Princess Telephone set made from the mid 1960's, and equipped with the polarity sensitive NE-25H4 Digi-Tone Dial ( Touch Tone ) and a Northern QNB4A-2 circuit board network. I've yet to find an actual Northern Electric schematic for this type of telephone set. I have a copy of Bell Canada's Station Installation & Repair Manual dated 1981, which does include a schematic for the pulse dial version of this telephone, but not the Digi-Tone version.
What I've prepared is what I call a "written" schematic, but it does not include the internal routing of the circuit incorporated into the network circuit board itself. It's strictly the connection points of the peripheral equipment and components of the telephone, including dial, handset cord, ringer and line or mounting cord.
Hopefully this information will be of assistance. The file listed is in "pdf" format.
Have a great week.
Jeff Lamb