you`re welcome ,
NONTHELESS there have been COPYCATS of some kind on the market.
I`ll give an example ,
have a look at this panasonic#-rq548 IBBN 7-02777 from 1975:
this one has been copied.
8(!) different brands were thrown onto the market with this shape:
.............and so far
differences :
other cassette drives with counter on bottom istead of top located one,
rectangle needle meter housings instead of round ones at the panasonic.
....
also: the panasonic cassette keys are built with more complex features : an integrated (red) record key was built in.
pana:
copy example:
(on the first view the copy`s version seems to have more tuner features ,but the pana equivalent was also on the market with 4 waves)