Problem: There appear to be either post schematic or post manufacture circuit updates done to the bottom of my Bi Polar Bear circuit board (PC00026Sx7) 300 watt BPJ output board.
They being the addition of 2 resistors.This amp had the wrong output transistors installed and they were replaced with the SM recommended replacement. 2SA1695 & 2SC4468 as well as the drivers and the bias transistor. The photos I originally took of the bottom of the board disappeared along with the hard drive of my recently deceased laptop! But I only lifted one leg of both resistors and I'm not sure about exactly where they were connected to.
What I've got: I need to figure out the destination of 4.7K ohm resistor (blue) "originally"/currently connected between R24 (1K) & R25 (1K) and looks like, by length, is destened for the emitter of TR14. There is also a 22K ohm resistor (red) that is "originally"/currently connected between the collectors of TR14 and TR13 and by length destined for a point between R28 (0.22 ohm) & R34 (0.22 ohm) or the Base of TR17. I'm hoping that someone that knows a bit about circuits can tell me if either addition makes sense, is wrong or maybe should connect to another point near by. I've included a shot of the board with the current positions of the resistors and a schematic shot of the circuit in question. Any help at all would be greatly appreciated.
They being the addition of 2 resistors.This amp had the wrong output transistors installed and they were replaced with the SM recommended replacement. 2SA1695 & 2SC4468 as well as the drivers and the bias transistor. The photos I originally took of the bottom of the board disappeared along with the hard drive of my recently deceased laptop! But I only lifted one leg of both resistors and I'm not sure about exactly where they were connected to.
What I've got: I need to figure out the destination of 4.7K ohm resistor (blue) "originally"/currently connected between R24 (1K) & R25 (1K) and looks like, by length, is destened for the emitter of TR14. There is also a 22K ohm resistor (red) that is "originally"/currently connected between the collectors of TR14 and TR13 and by length destined for a point between R28 (0.22 ohm) & R34 (0.22 ohm) or the Base of TR17. I'm hoping that someone that knows a bit about circuits can tell me if either addition makes sense, is wrong or maybe should connect to another point near by. I've included a shot of the board with the current positions of the resistors and a schematic shot of the circuit in question. Any help at all would be greatly appreciated.
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