Sony TC-D5M Portable Stereo Cassette Recorder Demo - for sale, link in description

To purchase this engineering wonder from the 1980s (ship to US buyers only):
- eBay: www.ebay.com/itm/285154866100
- Etsy: www.etsy.com/listing/14223615...

[@werwolf43]

Is it normal that the red REC lamp does not light up when recording when the power supply is connected, but only lights up when using battery or rechargeable battery????