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Help with Output Devices

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BiffW3

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I have been given some bare PCB's to a dual-mono amplifier. I'm currently sourcing parts for it and seem to be struggling with the k1529/j200 MOSFETS indicated on the schematic, 16 total. They are not the easiest things to find and when I do find them, people are selling them for $20/pr. Can anyone make any recommendations for alternatives? The friend that gave me the boards told me that Motorola MJL21193/21194 were offered as an "upgrade." These I can find and source for about $40 total. Is this an upgrade? Will they work? Do I need to make any additional changes? Up until this point, I've only built and designed gain-clone style amplifiers. This is my first foray into analog devices.
 

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The Chinese schematic shows bipolar transistors, not Mosfets. We cannot read the Chinese notes that might say how they are matched.
 
Unfortunately, I do not speak/read chinese either.

I did run it through Google Translate and this is what I got:
Description of Board
Debugging puping 0.5K resistor is disconnected palette of 100 ohm resistor adjustable output to zero.
1 ok so adjustable palette of 0.22ohm resistor voltage drop is 100 mv.
10.5K resistor connected to disconnected.


When I searched the above, I came back with the following.
M-9 testing:
1. first of all, please solder the 10.5kohm resistor with * on pcb to make it open circuit
2. adj W2 100 Ohm VR to make the mid point voltage to 0V
3. adj W1 10K Ohm VR in order to make the 0.22Ohm resistor 's voltage drop as 100mV
4. at the end, reconnect the 10.5K Ohm with solder gun.
 
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