Manufacturing of high-quality power connectors

The power circuit of this machine adopts a double-bridge rectifier and filter circuit, which can eliminate the 100Hz hum current leaked from the secondary center-tapped circuit to the amplifier
, allowing the signal current and ripple current to go their own way, effectively avoiding hum interference and intermodulation distortion. Shen VT1,
VTZ, VT3VT4 form a series symmetrical voltage stabilizing circuit, and the voltage stabilizing output is ±28V. 078L15 and 791d15 are three-terminal voltage stabilizing integrated circuits
, which provide stable ±15V power supply for IC 1. 781.15 and 791.15 can also be replaced by 7815 and 7915. F3 in the picture
is the current overcurrent fuse (0.5A) port.
    When making the port, pay attention to VT2, VT4, IC2. IC 3 must be installed with a large enough radiator . A layer of silicone grease should be applied between the device and the heat sink
. The heat sink of TDA1514A is connected to the ④ pin. Unless there is a mica sheet between the external heat sink and the integrated block,
it is necessary to directly connect the heat sink to the ④ pin with a wire to prevent possible short-circuit current from damaging the integrated circuit.