Here's some new bench data on the original audio amp interstage transformer. Note there is also a side chain interstage transformer which is different.
Inductance tests with hand-held Extech 380193 LCR meter
120 hz tests, series mode, unloaded
Primary
2 windings, each 470H, 116K AC ohm, 2660 DC resistance
in series as in circuit 1861H, 435k AC ohm, 5320 DC resistance
Secondary
932H, 224K AC ohm, 3790 DC resistance
Inductance tests with hand-held Extech 380193 LCR meter
120 hz tests, series mode, unloaded
Primary
2 windings, each 470H, 116K AC ohm, 2660 DC resistance
in series as in circuit 1861H, 435k AC ohm, 5320 DC resistance
Secondary
932H, 224K AC ohm, 3790 DC resistance
