Vintage 1970s JMF Engineering DT-70 Musical Instrument Guitar Bass Tuner + Cover

Vintage 1970s JMF Engineering DT-70 Musical Instrument Guitar Bass Tuner + Cover. I believe this is from the 1970s. I plugged it in & it turns on. Turning the range dial makes different lights light up. The number 99 initially came up then went away. Different numbers would come up depending on how I turned the dials (range, note).

I don't know how it works and don't have an instrument to test it. I have no idea if it works correctly or not. The cover has wear & could use a cleaning.

Ask all questions BEFORE making an offer or purchasing. Please read the description & look at the photos.

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