My CTK 720 isn't powering on from the adapter anymore but battery power is working. I bought a new adapter but it still isn't powering on. Can this be repaired?

"Casio CTK-501 Digital Keyboard Troubleshooting - iFixit" https://www.ifixit.com/Wiki/Casio_CTK-501_Digital_Keyboard_Troubleshooting

try plugging in without the bateries...Also check your adaptor as well as your ac requirements on your keyboard..It specifically calls for a Casio AD-5 Adaptor.

• 9V power supply; 850mA
• Positive sleeve/negative tip This needs to match your adaptor Good Luck

http://support.casio.com/pdf/008/ctk_720_01_e.pdf

Looks like you're in luck:


Power Supply AC Adapter for Casio Keyboards CTK 540 CTK 541 CTK 551 CTK...

PC drivers available at Casio
http://support.casio.com/en/support/download.php?cid=008&pid=20

If you have a MAC google casio driver for Macs by 3rd party.

Likely a problem with the power connector or the power adapter. Make sure you are using the original power adapter as often replacements don't work and universal adapters seldom work.

If you are running on batteries, they are either depleted OR may have corrosion on the contacts in the keyboard which is COMMON problem. If using an adapter, the cords chronically work loose. A last problem is the switching for using battery or adapter can have poor contacts. If you don't have an adapter, get one and get one SPECIFICALLY for the keyboard... I don't know how many I have had to tell they have the wrong adapter and that is why their unit won't work.

The adapter has a problem... likely a poor connection of input power that briefly contacts building up some voltage that is then stored in the capacitors in the adapter which then discharge quicklly when you turn on the Casio. The adapters with FIXED blades OFTEN have problems contacting the connections in wall receptacles and extension cords. You may need to bend the blades slightly or use a better receptacle like connector. IF your adapter has a three wire cord from it to the wall receptacle, those SOMETIMES don't seat well...

First verify with a voltmeter that the adapter IS producing the voltage it is supposed to.

The cords and internals of these often fail.

Anything beyond that will require servicing. One could oppen the unit and look for bad solder or cracked board NEAR the power input jack.

OFTEN the power connector in the synth get broken from the circuit board connections.

ALSO verify the adapter is actually putting out the correct voltage or slightly above it..

Just did it today. Hooked up CTK-720 to Imac with Snow Leopard (10.2.6) using GarageBand.
Steps: 1) Go to : http://code.google.com/p/casiousbmididriver/ 2) Download the CasioUSBMIDIDriver.plugin (see the two choices on the right side of screen) 3) Place the CasioUSBMIDIDriver.Plugin file into the MIDI Driver subfolder: Macintosh HD => Library => Audio => MIDI Drivers 4) Restart 5) Plug in USB cable, open GarageBand, turn on Casio 6) In GraarageBand Open New Project, Start by using Piano, Select Keyboard (command K) in the Window menu 7) You should see the keyboard being played on the screen.
PS: Thank you Francois Ferland.