Emitter is supplied by a 5V Zener,
collector to pin 6
Base and collector are bridged with a 100K resistor, and goes over another resistor to a diode to each driver.
Behind the diode i have 6V, after the diode 2V.
Somehow the 2V musst be suppressed. I will remove the diode to the driver, to check if there is something leaking.
collector to pin 6
Base and collector are bridged with a 100K resistor, and goes over another resistor to a diode to each driver.
Behind the diode i have 6V, after the diode 2V.
Somehow the 2V musst be suppressed. I will remove the diode to the driver, to check if there is something leaking.
The base is 3v lower than the emitter. That generally indicates that the transistor is defective.
If i open pin 6 again, i have 5V at the Base.
Pin6 on the maiboard goes to two resistors in series, with a ceramic cap paralleled.
Than it goes to a J111 Drain..
How does it works? Should it pulled down from the mainboard? It seems, that on the drive board everything is ok.
Pin6 on the maiboard goes to two resistors in series, with a ceramic cap paralleled.
Than it goes to a J111 Drain..
How does it works? Should it pulled down from the mainboard? It seems, that on the drive board everything is ok.
I found in my store a new FR transistor, and exchanged. No i have 0V at the collector, and 5V at Base and emitter.
If i heat up, it seems to stay ok with closed pin 6..
If i heat up, it seems to stay ok with closed pin 6..
Problem still there, but i think, i found it. if i heat up a diode in this circuit, going to a drive ic, the amp goes in protect. Marked with "A". I will see, if i can find something similar.
I have only T4 1N4148W with 4ns speed, the original has 1,2ns
could i use it, or is it too slow?
could i use it, or is it too slow?
i used T4 for testing. Wasnt the reason for switch off. Only two caps beside this diode..i will remove them .
Removed this cap, with 10uf,and used two with 4.7uf 35v.now the problem is gone. I hope the voltage will be OK. I measured 12v across.
I replaced the old diode back. Heating up the area and testing was good. No Protect anymore.
For the people reading this:
I called B2, they normally mount a fan in front of the drive board to get rid of this problem. Drivers are 2092s.
The 10uf Cap makes the problem. If heat up, it starts leaking.
For the people reading this:
I called B2, they normally mount a fan in front of the drive board to get rid of this problem. Drivers are 2092s.
The 10uf Cap makes the problem. If heat up, it starts leaking.
