Details:
10 pairs of precision paired MJ15024G/MJ15025G metal encapsulated transistors.
The main circuit adopts a five ring metal film resistor with an accuracy of ± 1%. The overall signal-to-noise ratio is good.
Advanced C1237 BTL horn protection circuit.
Parameters:
1. Transformer parameters: dual AC36 (800W), dual AC46V (50W), AC15V (20W)
2. Power: Pure Class A output 75 W/8 Ω, Class A and Class B output 120 W/8 Ω, measured under minimum distortion.
3. Total harmonic distortion: less than 0.01%. The load is 8 Ω, and the output power is measured under 120 watts of Class A and Class B.
Less than 0.005%. The load is 8 Ω, and the output power is measured under 75 watts of Class A.
4. Horn impedance: 4-8 Ω.
5. PCB size: 1. Input board 140 * 220MM,
2. Protection+amplification level power supply board 140 * 220MM
3. Output board: 167 * 390MM (including angle aluminum)
6. Each sound channel of the radiator must have at least 10 kg, otherwise do not adjust the static current too much.To set Class A 75W, the voltage at both ends of the output resistor is about 35mv, and the static power consumption will reach 450W.
Attention:
Check the wiring carefully to ensure that there are no errors.
The adjustable resistor of the output board adjusts the static current. The current decreases counterclockwise and increases
clockwise.
The bulb shall be connected in series at 220V mains for the first power on, and the static current shall be adjusted to the minimum
before power on.
The switch of the input board is balanced input upward and RAC input downward.
For Class A design, heat dissipation should be properly handled.
The transformer shall be used according to the design voltage and power. Too high or too low will affect the performance of the power amplifier board.
The chassis grounding point must be selected at the input end, otherwise a lot of bottom noise will be generated.
