Part of the export-only Lux receivers which went from R-1030, R-1033, R-1040, R-1050, R-1070 or variants such as R-3030 or R-3045. Nothing like a good Lux myriad of plethoric versionsvariants !
The R-1120A is a late (and last ?) version of the ealier R-1120 : out went the discrete output transistors, the DIN tape connector, the third 'speaker terminals for electrostatic speakers, the meshed grill protection of the back heatsinks and the visible output transistors.
In came a pre/main loop, NEC EBT 200MHz fT drivers, NEC 60MHz hi-fT output transistors (200W Pc each) and, late as ever, a Dolby FM switch and its (optional) circuit board.
Being a 1978 design, it sports a Realtime DC Processed circuit, being a 1978 Luxman, the R-1120A has constant voltage pre-driver circuits.
The preamp section boasts an MC stage with parallel FET P and N complementary circuit and source follower output circuit with low gate current leakage.
The RIAA eq section uses low amounts of NFb with open loop gain following the RIAA curve, therefore an equal amount of NFb throughout the entire audible range.
The 4-gang Dual Gate MOS-Fet FM section is operated by Luxman's CLL tuning system (Closed Loop Locked : it extends locking control to all elements involved - local oscillator, front-end, IF and detector) and the AccuTouch system which locks everything down one second after the tuning knob has been left alone.
Being a 1978 component, the R-1120A also has two rows of flashy red LEDs and could receive an optional Dolby FM board (DUA1070) which few people actually ordered, got or even knew it existed...