i could use some help with these drivers for the power supply. There may or may not be transistors missing. This is what i have.
q4_2 2sd669a
q3_2 2sd669a
q6_2 Empty
q5_2 2sb649a
q7_2 Empty
q8_2 2sb649a
q9_2 2sd669a
q10_2 2sd669a
are the empty ones i have for pnp drivers as well.?
q4_2 2sd669a
q3_2 2sd669a
q6_2 Empty
q5_2 2sb649a
q7_2 Empty
q8_2 2sb649a
q9_2 2sd669a
q10_2 2sd669a
are the empty ones i have for pnp drivers as well.?
Whenever you have an emitter follower configuration in power supply drivers, the PNP drivers will have their collectors connected to ground.
gate resistors value? I have burned up resistors and different readings as well.
15r-16.3-r 21.5r What should i use in
R104_2
R103_2
R99_2
R97_2
15r-16.3-r 21.5r What should i use in
R104_2
R103_2
R99_2
R97_2
i went with a 20R . I believe they had a 22R originally. but i had one fet in per bank the amplifier started and worked fine.
I proceeded to m install the remaining mosfets and the amp now draws current.
I proceeded to m install the remaining mosfets and the amp now draws current.
thanks perry a solder bridge just caused me to pull all my work apart. now its going back together.
All of the gates have 3.521ldc on them except one
IRF15_2 has 5.428vd
All of the gates have 3.521ldc on them except one
IRF15_2 has 5.428vd
something in that bank pulls the drive down when mosfets or a capacitor is in circuit. drivers, or possible something on the driver card?
Are you saying that the amplitude of the drive at the emitters of the driver transistors drops when you use a loading capacitor (~0.1uF) across the gate and source of the PS FETs?
I have a problem with the same amplifier. The customer himself replaced the inverter transistors and literally burned down again. All items checked. However, the inverter does not work. Looks for IRFP064 control signal too weak. I don't see any burnt path. It is possible that it is hidden under the adhesive or trafo. According to the meter, there is power and GND on the respective legs of the control transistors. If I skip the D669 and D649 transistor driver. The inverter starts. I will attach my entries regarding the elements, they may not be correct. I am sorry for my English I am from Poland
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Please don't post in a repair thread that was started by someone else unless you are trying to help them.
Start a new thread if you need help with a repair of your own.
Start a new thread if you need help with a repair of your own.