I recently purchased this older Unitrol Touchmaster TM4-0 off of ebay, and was very surprised when I heard that it had Touchmaster Delta tones instead of the old Dunbar Nunn style tones. I also noticed that its missing the yellow ignition wire for the RLS. Any ideas as to why this unit has Delta tones and why it's missing the ignition wire?
I've also attached a video showcasing this oddball Unitrol.
I've also attached a video showcasing this oddball Unitrol.