Anyone have any experience with a Bell Systems 2752 wall panel phone, 1752 or 752? I am working on a 2752 phone that has a bad speaker for speakerphone that has a open circuit. Anyone recall what ohm speaker was used for these speakerphones. Since the bad speaker isn't reading any resistance I can't tell what to replace the speaker with. It's next to impossible to find another 2752 to scavenge from or to check ohms of speaker. I have looked in every old manual that I can get my hands on and can't find specs for the speaker. Any help is greatly appreciated!