How about this, on cnet no less.... https://www.cnet.com/products/panasonic-rq-sw33v-cassette-player/specs/
Check out some of the sites on my "Another Cool Japanese Site" up in the boombox chat section, there's a ton of websites and blogs although you...
Cool equipment, back then they strived to be different, now-a-days everything seems to be a copy and there's very little variations.
If you get a chance look up the johnedwards threads on the old forum, I think he owned every unit in the series.
Early Toshiba Unit https://patents.google.com/patent/US4360174A/en?oq=US4119813A [ATTACH]
Sony with mono button https://patents.google.com/patent/US4641293A/en?oq=US4119813A [ATTACH]
Sony Mono Box https://patents.google.com/patent/US4109115A/en?oq=US4119813A [ATTACH]
Early Olympus Cassette and Radio Player https://patents.google.com/patent/US4119813A/en?oq=US4119813A [ATTACH]
Very early 1971 mono box https://patents.google.com/patent/US3560666A/en?oq=US3560666A [ATTACH]
Yamaha Headphones https://patents.google.com/patent/USD246242S/en?oq=USD276908S [ATTACH]
Altec Speaker https://patents.google.com/patent/USD250586S/en?oq=USD276908S [ATTACH]
This is for Longman, Pocket Computer! https://patents.google.com/patent/USD298623S/en?oq=USD276908S [ATTACH]
Sony Headphone https://patents.google.com/patent/USD292205S/en?oq=USD276908S [ATTACH]
Pioneer Loudspeaker https://patents.google.com/patent/USD291196S/en?oq=USD276908S [ATTACH]
Maybe a Panasonic Short Wave? https://patents.google.com/patent/USD254738S/en?oq=USD276908S [ATTACH]
It looks like an update to the TEAC Portastudio https://patents.google.com/patent/USD291196S/en?oq=USD276908S [ATTACH]
LG getting a little style to their boombox https://patents.google.com/patent/USD334191S/en?oq=USD276908S [ATTACH]
LG Boombox https://patents.google.com/patent/USD329852S/en?oq=USD276908S [ATTACH]
CD player https://patents.google.com/patent/USD313018S/en?oq=USD276908S [ATTACH]
Later model Toshiba with CD player https://patents.google.com/patent/USD310668S/en?oq=USD276908S [ATTACH]
Separate names with a comma.