80Wx2 high-fidelity power amplifier

It is an 80W × 2 two-channel high-fidelity power amplifier circuit composed of uPC1342V and 2SC2,987, 2SA1227 pairs of tubes
. This circuit also uses a multi-functional protection circuit. PC1237 is used as the full-function protection of the circuit. Table 2-34 lists
the manufacturers. Recommended output pairs for different output powers, from 25W to low. In addition to the tubes listed in the table,
Sanken fever tubes can also be used as output tubes, such as 2SA1216, 2SC2922, or 2SA1292.2SC3264, etc. When conditions
do not permit, cheap high-quality tubes IVU2955 2N3055 can also be used.
    When using LrPC1342V, a 60×60×1,5mm aluminum radiator is required. There is
an adjustable bias circuit connected to pin 78 of the circuit. After the circuit is powered on, the 51m adjustable resistor can be adjusted to keep the output tube quiescent current at lOOmA.
The capacitor connected between the left and right pins 06 and 7 is a compensation capacitor with a maximum capacity of 100pF. If the circuit works well without self-excitation, the capacity of the compensation capacitor should be reduced as much as possible
.
    In order to give full play to the function of the high-fidelity power amplifier , the capacity of the power transformer should be large enough, and the capacity of the filter capacitor
should not be less than 1000LeFo. The internal resistance of the power supply should be as small as possible.