Can you identify the manufacturer of the device in the attached photo.
It was used a visual indicator for hearing impaired in an apartment.

Any other device suggestions are welcome.

E.G. A visual device (normally 24V) to connect to a doorbell (normally 16V).

[img][img]https://i.postimg.cc/RhF1GHZL/hearing-impaired-visual.jpg[/img][/img]

I haven't seen that device but I was thinking how easy it would be to build something like it. If I had a hearing impaired friend who needed one, the intercom interface would be the only unknown. Doorbell voltage is either there or it isn't. Telephone has a huge difference between DC Tip & Ring and AC Ringer. The intercom is the only thing that I didn't just design in my head. I would opto couple all three to drive super bright LEDs on the annunciator.
Joe