Magnetic tape head azimuth assembly, from Motorola 1978. If anybody is into digging into tape heads here's a good start. https://patents.google.com/patent/US4158212A/en?oq=US3943564A
Portable radio receiver with detachable speaker unit Submitted in 1976, this Sony Patent looks like the beginning of the Walkman. https://patents.google.com/patent/US4194157A/en?oq=US3943564A
Nice pick-up walkman archive, I have the data-bank/calendar version and there was also a TV version. Casio was coming out with some really neat "gadgets" back in the 80s-90s, I miss checking out their displays at the local malls. Here's Casio's Wikipedia from Japan, use Google Translate to get it in your language. https://ja.wikipedia.org/wiki/カシオ計算機
I borrowed these photos from an ebay listing. https://www.ebay.com/itm/Vtg-Walkma...+accessory&_from=R40&rt=nc&_trksid=m570.l1313
Some of these might be repeats, hopefully they're fresh, there's more photos and a ton of information in the links. Radio Tuner https://patents.google.com/patent/USD326652S/en?oq=USD326652S
Cassette tape recording and/or reproducing apparatus including an improved head base assembly https://patents.google.com/patent/US4739423A/en?oq=US4739423A
Battery holder of single head minimum size cassette tape player https://patents.google.com/patent/US4661865A/en?oq=US4661865A
Another small Olympus Ultra-small portable sound reproducing apparatus https://patents.google.com/patent/US4303807A/en?oq=US4303807A
Sony Watchman from disk? I think Techmoan did one of these. https://patents.google.com/patent/US5265083A/en?oq=US4561084A
Early versions of the personal cassette player, these are all mono but they're starting to get cool looking. https://books.google.com/books?id=f...dAhXkHzQIHQVpCLQQ6AEIMzAD#v=onepage&q&f=false