I have a Casio electronic keyboard WK 1800. The transformer is broken, I guess. We brought this keyboard in India. It broke there although we had took precaution with the electrical network of India. Is it possible to have it repaired and where? We live in Ottawa. Tks. G.L.

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.

Question moved from Cars and Trucks to a Casio Keyboard one.
Easy enough if you can find the part.

https://www.google.com/search?q=casio+wk-1250+parts+diagram

casio WK1250 Parts and Accessories - PacParts

https://www.pacparts.com > model > model_id=WK1250
Mfg / Model No, Description, PDF, Year. casio WK1250, Musical Instrument: Electronic Keyboard, 1998. The following parts are available for the model listed ...

Casio WK-1250 Repair Parts and Accessories - Syntaur

https://syntaur.com > keyboard > keyboard=2080
Casio WK-1250. Released in 1998. The WK-1250 is a 73-note consumer keyboard with built-in speakers. Synth. All photos are copyrighted by Syntaur, ...

Casio Keyboard Junkyard: Welcome

https://casiokeyboardjunkyard.com Used accessories, parts and stuff for Casio Keyboards ... CASIO WK-1200, WK-1250, WK-1300, WK-1350 models are basically the same and use the same parts.

Casio Repair Parts - Keyboard Kountry

https://www.keyboardkountry.com > keyboard-parts
Casio Repair Parts ; Yamaha Brand Key Lube (Small). $3.80 ; Casio CTK-560L Ma1M Light Boards. $9.95 ; Replacement Keys for Casio CTK-491 and Others. $10.95.
Missing: 1250 ‎' Must include: 1250 ..

https://www.amazon.com/casio-keyboard-sustain-pedal/s?page=4&rh=i%3Aaps%2Ck%3Acasio%20keyboard%20sustain%20pedal

From CASIO, duhhh ?

These pads can be replaced ( providing Casio still have spare parts ) There are a lot of screws to undo to get inside the keyboard, then remove any PCB above the pad, replace and reassemble.

or

Contact your nearest Casio service centre

Do You use original CASIO power adapter for this keyboard?
Some CASIO (CTK-5000) models require inverse voltage polarity than most of others adapters have!!! RISC OF BURNING OUT ELECTRONICS!!!

Here is one:

http://www.amazon.com/Casio-AD-12MLA-Adapter-Power-Supply/dp/B00029HDT0

and another, less expensive on Ebay:

http://cgi.ebay.com/Genuine-AD-12MLA-12V-2-5A-2500mA-AC-PowerSupply-ADAPTER-/390280683299?pt=LH_DefaultDomain_0&hash=item5ade8a9f23

Unfortunately the adapter jacks are a bit of a weak point on many keyboards but it is quite seldom the jack socket itself that is at fault.
Often the sockets are soldered directly on to the printed circuit board and are prone to either one of the soldered legs breaking, or even the circuit board itself cracking around the jack socket. 
Whilst it is generally possible, with care, to resolder a broken leg on the socket if the actual circuit board has cracked the whole board will have to be replaced.
If the actual jack socket itself is damaged it should be possible to snip through the legs and remove it before soldering a new one on to the stumps of the old legs. this is likely to prove easier than trying to solder directly onto the circuit board, unless this is something that you are experienced at doing.

Apparently you can purchase a full service manual for the Casio WK-1200 here for a modest price but I have not used this source myself so cannot vouch for how good it might be.http://www.tradebit.com/filedetail.php/2084335-repair-manual-casio-wk-1200-electronic-keyboard

This is a link to WK-500 owners manual.....SD Card information is on pages E-59 thru E-64...
http://support.casio.com/pdf/008/WK200_500_e.pdf

no but can't afford to join any plan