At the 15V end, on top is a TC4066 Quad Switch, and underneath is the TL494 PWM controller.
The one you have black circled is the other TC4066 Switcher. It is underneath the signal transformer over on the Input side, not the 15V side.
Top Layer ICs:
AD8677 Op Amp
5-pin single gate logic inverter, part number ?
3-pin dual diode, part number ?
TC4066, Toshiba Quad Bilateral Switch
2 transformers: Left one is 1:1 signal; Right one is 15V primary to +/- 6V secondary power.
Bottom Layer:
TC4066, Toshiba Quad Bilateral Switch
TL494, PWM Control Circuit for SMPS
3-pin dual diode, part number ?
