Both parts and finished boards are the price of two channels, but without 4 pairs of output power tubes, compatible with ON series power tubes and Toshiba 2SC5200.1943 and other pairs of tubes
The kit is a spare part and needs to be welded and debugged by yourself.
Please choose kits and finished boards according to your personal ability level
The schematic diagram of the kit, you can download this file package, there are schematic diagrams of all the kits in this shop
http://pan.baidu.com/s/1gfgF22B
Marantz MA-9S2 is a more classic famous machine. The original machine is 3W and it adopts the topology of the hdam-sa module. The input is a special diamond buffer circuit. The I/V mirror circuit is used between the voltage levels, which is very good. Front and rear matching characteristics. The feedback form of the final circuit is current feedback, and the load control is very good. If the input capacitor is short-circuited, because the circuit itself has no feedback capacitor, it can be regarded as a full DC amplifier circuit, and the electrical performance of the circuit is quite good ;
This kit refers to the circuit of the machine, and adds a DC servo circuit, so that the midpoint can be free from debugging, and the midpoint has only a single MV level change. The whole machine only needs to adjust the quiescent current, which is to adjust the trimming potentiometer. Make any resistance voltage of 0.22 ohm on the board be between 10MV and -40MV. Of course, if you want to make a machine, you can adjust it to more than 100MV. Pay attention to heat dissipation.
Voltage range: DC+-30V---DC+-63V
Power: 8 ohm 150W (tested under DC+-63V)
Area: 109MM X 82MM is relatively small and can be easily installed
In actual audition, there is not much imaginative cold and fast feeling, but it is delicate and durable. The circuit selection tube is mainly based on the famous Japanese tube 2SC2240.970 1145.2705, and is precisely matched.
The 1 pair 2240.970 with *** on the board does not need to be paired, pay attention here
The board wiring is also simple, the board is marked with a number. OUT is the speaker output, and GND is grounded. VCC is connected to the power supply, VSS is connected to the negative power supply
Comment
Input capacitance 2
1K adjustable 2
0.22 non-inductive resistance 8
10 Five-color ring copper foot resistance 10
100 five-color ring copper foot resistor 4
22 Five-color ring copper foot resistor 8
220K five-color ring copper foot resistance 4
2K2 five-color ring copper foot resistor 6
330 five-color ring copper foot resistor 2
390 five-color ring copper foot resistor 4
470 five-color ring copper foot resistor 8
470K five-color ring copper foot resistor 4
75 five-color ring copper foot resistor 8
7K5 five-color ring copper foot resistor 4
10 resistance--1/2W 4
2K2 Five-color ring copper foot resistor 2
33/0.5W 718 factory high standard 4
4R7-0.5W 2
LF353 2
LED red 8
C2705/1145 precision matching 4
C2240/970 precision matching 8
C2240/970 2
IC Block 2
D667 2
B647 2
D669 2
12V voltage regulator tube produced by MOTO 4
4148 12
104 capacitor 10
221 capacitor RIFA 4
100U/16V 8
1U BP/25V 4
10u Panasonic 2
220U/50V FW or Panasonic FC 8
C5171/A1930 2
Cooling 4
PCB 2