Garagestudio - Found this speed calibration cassette for old cassette players among my old electronic stuff, old school 🤔 I think it was a long time since I had used it 🙂 . . . . . . #
London Vintage HiFi Market - Calibration Cassette Speed Playback Professional Test Tape 3000 Hz (3 kHz) frequency Type II Clear Chrome for Stereo Cassette Deck, Walkman, Answering Machine, Boombox, Cassette Player -
Test, Measurement & Calibration for Cassette | AudioDefine Records