I knew my ITECH 7321 programmable AC source would be useful one day @CuriousMarc

I knew my ITECH 7321 programmable AC source would be useful one day @CuriousMarc

Uploaded June 2026 | Updated September 2026, 1 week ago

Old phones need 90V 20Hz AC to activate their ringers. The ITECH can go down to 45Hz. Close enough I guess!

I knew my ITECH 7321 programmable AC source would be useful one day

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I knew my ITECH 7321 programmable AC source would be useful one day