Check the listing for details. JC-2 Class A Fully Symmetrical FET CPI Parallel Power Supply Pramplifier PCB. Condition: New. Listed at 8.99 USD. Introduction: The circuit refers to the well-known JC-2 circuit design, fully symmetrical FET input, voltage level up to 20mA-25mA Class A output, mellow and durable, delicate, crystal clear, well-balanced, very close to the style of a tube amplifier, and very cost-effective , Because it is a fully flat symmetrical structure, the midpoint is very stable and does not require input and output capacitors. The power supply part adopts a class A parallel connection, and the music is very dynamic. Parameter: Input voltage: AC 15V--0--15V Amplifier type: Class A Input stage: 2mA Voltage amplifier stage: 20-25MA Gain: 5 Times PCB Size: 115mm * 93mm NOTE: This is a Bare PCB, and all parts need to be matched by yourself. Debugging instructions: 1: Measure the GND voltage between A and B, and adjust the 2K (202) adjustable resistor voltage to DC+/-15V. 2: Measure the voltage at both ends of the 1.5K resistor, and adjust the 2K (202) adjustable resistor voltage to 2.5-3V. 3: Measure the output midpoint voltage and adjust the 500R (501) adjustable resistor to make the voltage close to 0mV.