Replacing batteries with a plug to standard 120V outlet?

My daughter got a great little toy that really helps her to get off to sleep. However, it eats through batteries. I'd really like to wire something up that would replace the batteries with a plug to a standard wall outlet. Is this possible? It runs on 4 C cell batteries. I am fairly handy with a soldering iron.





If no, I may have to buy stock in Duracell.





Thanks!

Replacing batteries with a plug to standard 120V outlet?
You have to be careful in choosing an AC to DC wall transformer type of supply. The rating on the transformer, for instance, 6v @ 300ma, actually means that at the load of 300ma, the voltage will be 6v. Without a load, the voltage could be 10 to 15 volts because there is no regulation in most of the wall transformer power units. You have to know how much currrent is being used from the 4 C cells during the toy's normal usage to get an accurate reading.
Reply:I'm not sure of anything like that, but have you tried rechargable batteries? They can be recharged quite a few times....
Reply:Since you are using 4 c sized batteries, your small appliance is using 6 volts of DC 4x1.5v. I am not sure how much Amperage, that would need to be calculated. If this device has a jack for a transformer, it should tell you what it requires. For example it might say 6VDC 2000mAh. And in that case you would have to find the right transformer from your local electronics parts superstore. If you have to wire it yourself, you will need to get the right step down transformer that can convert 120V AC to approximately 6 V DC and whatever amperage is necessary.
Reply:4 C batteries, likely used in parallel for 6v total. If it goes through batteries a lot, then it also has pretty high power drain. Check for a label which gives the voltage and current in ma (milliamps). If not ma, then watts or milliwatts. Watts divided by 6v is amps, and milliwatts divided by 6v is milliamps.





Go to Radio Shack and they will have an AC power adapter for the voltage and milliamp rating you need. 6v is 6v, and that's what you need, but if the milliamp rating is higher on the adapter, that's okay. It just means there is room to spare.





Cut the connector off the end of the AC adapter, bare the ends, and solder them to the battery tray terminals in the toy. Make SURE of the correct polarity. Replace the battery cover to protect the soldered wires inside. You may have to use a file to create a small hole for the wire so it doesn't get pinched.





That's about it. Risk of injury is almost non-existent as 6v is not enough to do anything. Even if the wires got pulled out and touched together, the worst that would happen is the AC adapter would get very hot and just burn out inside. You'd never even know it to look at it.
Reply:I would not try it unless it has a jack to add an ac adapter. 4 C batteries is 6 volts whereas a electrical plug would be 110-120 volts. Please be careful. Also, have you considered rechargeable batteries?