MAins adapter advice

[puternut]

We have an German music box bought about 10 years ago along with a mains adapter. The adapter has now gone missing and needs replacing

The sticker on the bottom of the box states that it requires 9v and 1A supply. The plug seems to be a 5mm

Is this what I should look for as regards the replacement adapter or should it be higher/lower in the output from the adapter to build in a bit of undercapacty so its not at full power.

Any help appreciated

[roger]

you can get multi-voltage adapters with interchangeable plugs in plenty of shops (Maplin springs to mind) just make sure it will give 1Amp or more. Do not use it on the wrong voltage, if you go over on volts you may damage your music box irreparably. Going over on the amperage is fine as the box will draw what it needs, going under may stop it working

[scotman]

This is a selection of what is available in Maplin. If there is a shop near you you could take the item in and speak to someone about the appropriate power supply you need.

[scotman]

And this is is the link I forgot to post

http://www.maplin.co....teria=dc+power+supply

[Hymie]

roger & scotman have given good advice – I would add that you should purchase an adapter having an input rating 100-240V (scotman’s Maplin link adapter meets this requirement), to be on the safe side.

Those rated at a single input voltage are likely to employ a linear transformer to give the 9V output. The problem with this type of adapter is that the no-load output voltage can easily be up to 150% of the output rating – resulting in over 13V being supplied to the equipment (which could cause damage).

Those adapters having a wide input voltage range (100-240V) will be regulated such that their actual output voltage will be close to the rated voltage, from no-load to full load current.

[scotman]

I was going to post more following Hymie's reply but having read your question again I notice that you have not stated whether the music box needs an ac or dc supply. This matters!
Is this marked on it anywhere?
The symbol for dc is usually a pair of short horizontal lines. The lower one will be solid and the upper one dashed. For ac it will be similar except the the upper line will be wavy.

[puternut]

Thank you people for your help. I will definitely go to Maplin and check it out. It shows my local store has at least 2 in stock of a variable adapter up to 3A.

http://www.maplin.co....c-power-supply-228639

As for scotmans information there is no symbol on the sticker as regards wavy or straight lines but does need to be DC.

The only drawback is that the stcker doesnt doesnt give the polarity of the centre pin however most seem to be available with reversible power tips.

[puternut]

Sorry wrong link - thats a 12v to 9v one but I have looked at loads

http://www.maplin.co....ma-power-supply-48908

[seadogg]

If you are lucky the music box will have a protection diode so if you connect it up on the wrong polarity the only thing that will happen is that it wont work. If you take into Maplin they may check for you..