Well, after all of this - I've had my fun. I wrote up a 3 part series on all of this, it's mostly all teardowns of various broadcast / receiving equipment:
Part 1 (Philips PM5687 encoder/modulator & PM5686A modulator):
https://www.mattmillman.com/remember...ment-teardown/
Part 2 (Reviving an Arcam Delta 150):
https://www.mattmillman.com/remember...mething-fancy/
Part 3 (Philips PM5688 Test Receiver):
https://www.mattmillman.com/remember...iver-teardown/