Kicker ZX700.5 transistor question

[dinoo]

Hello,

I have a Kicker ZX700.5 Amplifier.

I measured that the IFR640 transistors are broken.
But on the left side there are 4 transistors IRF9640.

My question is: Are the IRF640 supposed to be at this location or should it be also IRF9640.

I uploaded the pictures, all help are welcome.

 

[Perry Babin]

Two 640s and four 9640s is what it should be.

 

[dinoo]

Thanks Perry, i replaced the resistors and the irf640 as you can see on the picture.

I turned the amplifier on it seems that the protection light is turning off, but the subwoofer channel is humming without any tulp connections connected to the amplifier.

I re-measured every thing and i saw the following locations are defective:

- Location: Q209 -> Part numer DY713
- Location: R210 -> SMD Resistor code 911 (910 Ohm)
- Location: R205 -> SMD Resistor code 4R7 (4,7 Ohm)
- Location: R202 -> SMD Resistor code 4R7 (4,7 Ohm)

Does anyone know the equivalent part for Location Q209 with part number DY713 ?

 

[PapaZBill]

Q209 is KTA1661y PNP and Q208 is the compliment (CY) KTC4373y NPN. Replace any defective transistors and their compliments.


When you say defective, do you mean shorted,open?

Do you hear the relay click?

Can you localize the humming? The Power Supply Transformer for the sub channel has a tendency to hum or buzz and can be remedied by spreading the leads away from the core and a little silicon around the transformer to reduce vibrations causing the hum.

 

[dinoo]

Thanks for your reply.

At this moment the Q209 is defective with that i mean that it is shorted.

When i connect a speaker to the sub channel and i turn the amplifier onn without a tulp signal input, the speaker cone is moving. And when i turn the gain level up the speaker is moving harder.

When i turn onn the amplifier i hear the relay click. Sometimes i hear the humming from the transformator but i think it is not necessary to fix the humming from the transformator.

 

[PapaZBill]

I would recommend that you replace Q209,Q208 and any resistors that are out of value.

FYI, if the board is not clamped in the chassis it not a good idea to run the amp with a speaker or dummy load and will damage outputs and power supply.

If the board is clamped in the chassis, make sure that all chassis screws are installed so that the board is properly grounded to the chassis.Improper grounding could be the reason for the humming.

 

[dinoo]

Oke i will replace Q209 and Q208 and the resistors.

What are the equivalent parts for Q209 KTA1661y PNP and Q208 KTC4373y NPN ?

 

[dinoo]

Is it possible to use an other part instead of KTA1661y cause i am not able to order this part.