Sansui AU-7500 volume control problem - need replacement

If the volume wheel on your Casio WK-200 keyboard is spinning all the way around and not stopping at the "min" or "max" positions, it is likely that the potentiometer that controls the volume has become faulty or damaged. A potentiometer, or pot for short, is a type of variable resistor that is commonly used to control the volume on electronic devices.
Here are a few troubleshooting steps you can try:

1. Power off your keyboard and unplug it from the power source.
2. Remove any batteries from the battery compartment.
3. Locate the volume potentiometer inside the keyboard. It should be near the volume wheel and will have three pins or legs.
4. Check the potentiometer for any visible signs of damage, such as cracks or broken pins.
5. Gently wiggle the volume wheel while observing the potentiometer. If it appears to be loose or wobbly, it may need to be replaced.
6. If you have experience with electronics and soldering, you may be able to replace the potentiometer yourself. Otherwise, it is recommended that you take your keyboard to a qualified service technician for repair.

If the issue persists after attempting these troubleshooting steps, it is likely that the potentiometer needs to be replaced. In any case, it is best to seek the assistance of a professional technician to avoid causing further damage to your keyboard.

If your Cambridge Audio Azur 640A V2.0 amplifier is not responding to the volume buttons on the remote control, there could be a few possible causes. Here are a few things you can try:

1. Check the batteries: Make sure that the batteries in the remote control are fresh and inserted correctly.
2. Check the remote sensor: Make sure that the remote sensor on the amplifier is not blocked or covered by anything. Also, ensure that the remote sensor is pointing towards the remote control.
3. Check the remote control functions: Make sure that the remote control is in the correct mode, and that you are pressing the correct buttons for the volume control.
4. Check the connection: Make sure all the connections between the amplifier and other components are secure and tight.
5. Check the potentiometer: The potentiometer (also known as the volume control) is the component responsible for controlling the volume of the amplifier. If the potentiometer is not functioning properly, then the amplifier will not respond to the volume buttons on the remote control.
6. Contact Cambridge Audio: If you have tried all of the above steps and are still unable to get the remote control to work, contact Cambridge Audio technical support for further assistance. They will be able to provide you with additional troubleshooting steps or advice, or they may need to send a technician to repair or replace the amplifier

Sansui QRX-7500 Manual - Four Channel Receiver - HiFi ...

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May 21, 2014 - sansui qrx-7500 four channel receiver. Sansui QRX-7500 ... service manual English - honestsoul99. Related Catalogues. HiFi Buyers Guide.

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The potentiometer doesn't need to be replace, it has collected dust inside causing the intermittent operation. Buy a contact cleaner/conditioner to spray inside it and move the potentiometer clockwise and counter clockwise a few times until the dust inside it is gone.
Check this link to find a contact/conditioner cleaner or you can try spraying rubbing alcohol but this could because alcohol doesn't not lubricants properties.
Let me know if you require further assistance.

There is a break in the potentiometer ( volume controller) of the headset. Your carbon track or the contact sweeper is losing touch with the carbon track.
Replacement of the controller potentiometer is needed.

It sounds like your volume control is dirty. You will have to disassemble the amp enough to get access to the volume potentiometer which is soldered to the circuit board. There will be a square hole in it that you can spray some contact cleaner into the control. Use only contact cleaner as anything else could damage the control. Use a small squirt and rotate the shaft. If this doesn't solve the problem you may have to replace the control. While you have it apart, examine the solder side to make sure all the solder joints are perfect especially those on the controls. A bad solder joint can also cause the same problem. Before you take the amp apart unplug the power with the amp on and the volumes turned down. This will discharge the capacitors so it will be safe to work on. I hope this helps.

You will have better luck finding it if you describe what control it is and what model it is from. Can you please update this with that info?

Thanks,
Dan

Mike,

It depends on how you intend to use it, your technical skills, and how much money you're willing to put into it. If your intent is to use it with a LCD / Plasma home theater system, you would be better off purchasing a new receiver.

If you want to keep it for some other purpose, and have the technical skills and tools necessary to repair it yourself, I would recommend purchasing a service manual for your receiver.

The other alternative is to find an electronics repair shop and get an estimate on what it would cost to fixt it.

In some cases, problems such as fuzz in the volume and balance controls, can be fixed using a high quality non corrosive electronic contact cleaner. This type of "possible" repair works best with potentiometers. However, there's no guarantee contact cleaner will correct the problem. It may be necessary to replace the components.

If component replacement is necessary, the service manual will be an invaluable asset when it comes to finding a compatible replacement part.

I can understand why you might want to get it repaired as I'm a fan of Sansui, Nakamichi, and other like equipment. I currently have a Nakamichi receiver that has the same problem with the volume and balance controls. At some point, I'll take the time to repair it.

For now though, I purchased a new receiver to connect to my home theater system and I'm actually glad I did as the new receiver is more compatible with the hardware available on the market today.

On later model Sansui tv's, you can bring up the menu by pushing both volume buttons on the front of the set at the same time. After the menu is on the screen, you can navigate using the channel and volume buttons.

You might try replacing the connection cables. Old cables can cause the problem you have experienced.