Add an AC adapter to a battery-powered device

Step 3 What do you need? Parts and Tools

The parts you need to add an AC adapter are fairly simple, but harder to find than I expected. I ended up going to Radio Shack -- they carry specific-voltage adapters, individual tips, and panel-mount sockets to match the tips. At most places you have to by a "universal" adapter, and can't get the sockets at all.

For the TinyLove mobile, which uses 3 AA batteries, I bought

4.5V adapter (700 mA)	273-1765
Size "M" (2.1mm ID, 5.5mm OD) plug	273-1716
Size "M" panel-mount socket with switch	274-1582

For your application, choose an adapter with an output voltage that matches the type and number of battery your device uses.

You will also need lengths of thin (24 gauge or smaller) wire, one with black insulation and one with red. I cannibalized mine from some left-over four-conductor signal cable. Start with 6" lengths and trim them back when doing the soldering (Step 5). A wire stripper will be quite handy, but someone with some skill (not me) could use some small wire-cutters or scissors.

You'll need some tools: The TinyLove mobile is held together with weird triangular-bit screws. I found the bits at McMaster-Carr Industrial Supply (items 5941A11 through 5941A14).

A 21/64" bit will make the exact hole needed for the panel-mount socket. You could also use a 1/8" Dremel bit, followed by the Dremel ball grinder to enlarge the hole.

A soldering iron, solder and flux are needed to connect the wires. A solder-sucker might be helpful, too, when disconnecting the leads from the battery terminals.

Comments

[redtux777]

I have 4 AA batteries in series in golden tee golf game I have. The batteries last 3 to 4 hours.
I am trying to do the math on that. Does that mean I would need 6v .5A power cord?

[kelseymh]

That sounds about right, based on typical AA capacities. Just to give yourself some headroom, you might consider a higher-current supply (say 6V @ .75A or 1A).

My apologies for the delayed response.

[viv_virus06]

i'm planning to run my remote controlled helicopter on ac adapter. i know that it use 9.0V but i don't know what mA should i buy. can you help me?

[kelseymh]

Do you mean you want to run the control box from an adapter? You obviously can't connect the helicopter itself to an AC adapter; it won't be able to fly :-) Did you read the manual? Usually toward the back there's a specifications sheet that should tell you the voltage and current usage.

[viv_virus06]

i'm connecting the ac adapter to the remote, or the controls. it requires 6 1.5 volts batteries. the box only specify the voltage requirement and the mAh. i cant find the mA requirement. can i use any 9v adapter without taking note of the current usage requirement?

[kelseymh]

Hmmm....yeah, that's not enough information to solve the problem. In principle, you could measure the current draw with a multimeter and four-lead bridge, but it's not important. Choose an adapter with a high current rating. The remote will only draw as much current as it needs; as long as the adapter can supply at least that much current, it's fine.

[viv_virus06]

thank you very much! you helped me a lot.

[viv_virus06]

anyway, how can i set the polarity of the adapter to its correct setting?

[jayhawk67]

i have a fountain that requires 2 double a batteries what adpater should i use?

[kelseymh]

Each battery is 1.5V.  If they're connected in series, you'd need a 3V adapter.  If they're connected in parallel (unusual), you'd need a 1.5V adapter.

[jayhawk67]

ty very much