Electrical parameters:
Note: 1pcs board is mono channel. Two-channel stereo need 2 pcs
Size:99*60*35mm
Supply voltage: DC ±24V to ±55V (transformer Double 18V~Double 35V)
4 ohm speakers because the current is large, the heat sink needs to be large enough. The voltage is recommended not to exceed ±40V.
Signal amplification tube: brand new pure imported ON (Anson US) MPSA56 MPSA06
Voltage amplification tube / push tube: ON (Anson US) MJE340/MJE350
Last-level big pipe: pure imported Sanken 2SC2922/2SA1216 (17 amps 200 watts)
Input coupling: West Germany ERO 1813 10UF/100V
Power Decoupling: Nippon Chemical
Conversion rate: 35V/us
Distortion: 1KHZ is less than 0.0006% 10KHZ is less than 0.006%
Frequency response: 20HZ~20KHZ (+0DB, -0.5DB) Note: Non-3DB
Output power: ±55V 8 ohms: 125 watts 4 ohms: 200 watts (power supply is ideal)
Multimeter DC file MV value /0.22 = quiescent current measured. If the test point value is DC 6.6 MV, quiescent current = 6.6 MV/0.22 = 30ma greater than 10ma, the crossover distortion is avoided.
Debug:
1.This power amplifier board is positive and negative DC power supply (±24V--±55V). Do not connect the transformer output directly to the board. The transformer output must be rectified and filtered before docking with the board. Be sure that the positive and negative are not reversed.
2.The heat sink must be installed before the board is commissioned. The large tube and the temperature supplement tube must be installed on the same heat sink. The temperature compensation tube must be able to reliably sense the temperature of the large tube and each major must add mica insulation sheet (we will distribute Then use a multimeter to check if the heat sink and the power amplifier tube are insulated.
3.will short-circuit the input terminal to ground during debugging to prevent ambient noise.
4.The advantages of the mono power amplifier board, the chassis selection is flexible, but the ground loop problem must be considered. Old burning has the responsibility to know that the first burning needs to learn (the network search amplifier is grounded a little). The only point of connection between the whole machine and the chassis is the merge point of the ground lines of the two RCA input sockets. The 220V socket ground wire is connected to the building's equipotential terminal and can be connected to the chassis. If the 220V socket is floating, remember not to connect to the chassis.