Black Magic Telephone Ring Generator – 20Hz Sine Wave, 12V DC In / 86V AC Out

Alright, so here’s the deal—this little black box is a proper telephone ring generator.

You give it 12 volts DC, and it pumps out a clean 86V AC sine wave at 20Hz.

That’s the magic frequency that makes old-school telephone bells ring.

Whether you’re restoring a vintage rotary phone or testing some telecom gear, this is the part you need.

Brand new, still in its original packaging.

Made by Cambridge Electronics Laboratories, model LS128620, and it’s built over in Thailand.

No scratches, no dings—just fresh stock ready to go.

If you’re into retro telecom projects, this is your ticket.