re: The RCA Ports on the back
From memory, I beleive these are pre-amp out and and pre-amp in - on the UK version it was a Din Plug with the wires crossed over but on the Beomaster 5000 (1980's) had phono plugs so maybe it's the same on the BC7000. The intention was that you could connect a graphic equaliser in between which was all the rage at the time or I guess a power amp. I once had a 7007 and experimented with the pre-amp out into a Quad poweramp. I might be wrong but am pretty sure this is what they're for.
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