6v Power Supply

[baldlimey]

I have a clock which requires a 6v power supply which I currently run off 240v using a transformer, is there such a thing as a 12v to 6v 'transformer' which I could use instead.

 

Cheers

 

Peter

[paulcatchpole]

If it doesn't use much current, you could knock one up easily enough if you're handy with a soldering iron.

 

Some of the car laptop supplies might adjust down to a 6v setting, but I'm not sure why they'd bother selling one that does... I've got one of those on my Watch List, at something like £2.88 each, though I didn't check what voltages it does.

 

Or, perhaps it might be happy on 5v, and if it takes less than 500ma, then you could use a car USB power supply - I paid 99p each for two recently on Ebay. Stick a USB cable in it, and fish out the 5v supply to power it. Might be worth a go just to see.

 

PC

[Bones]

yes. Maplins do it. It steps 12volt down

http://www.maplin.co.uk/universal-3a-dc-power-supply-228639

 

My link

 

they also do one that steps it up.

[paulcatchpole]

http://cgi.ebay.co.uk/Universal-Car-cigarette-lighter-power-supply-1-5-12v-/380347162913?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item588e752121

 

Good find, Bones.

 

The Ebay one above is less powerful though the same idea, but cheaper and should do the radio I'd have thought...

 

PC

[Chalky]

You could build one a lot cheaper. Provided it's only a low current you could use a low drop out regulator LM2490 (maplin AV22Y) and wire it up as shown on the web page. This will give you 5v. If you connect a 1n4001 diode in series with the earth pin on the regulator this will lift the voltage to about 5.7V which will probably be ok.

Alternatively there's an adjustable powersupply kit k18231A (maplin VE58N) that will do the job.

 

The above will convert the excess power to heat. To do it more efficiently you'll need a switching power supply but those are more complex DIY.

[Nickhlx]

You could build one a lot cheaper. Provided it's only a low current you could use a low drop out regulator LM2490 (maplin AV22Y) and wire it up as shown on the web page. This will give you 5v. If you connect a 1n4001 diode in series with the earth pin on the regulator this will lift the voltage to about 5.7V which will probably be ok.

Alternatively there's an adjustable powersupply kit k18231A (maplin VE58N) that will do the job.

 

The above will convert the excess power to heat. To do it more efficiently you'll need a switching power supply but those are more complex DIY.

 

You could also do it with a LM 317T and a couple of resistors / capacitors for about £3 and a box to put it in...

 

Would be pleased to forward a circuit if you can / want to make one...

 

Nick

[Robin2]

You could build one a lot cheaper. Provided it's only a low current you could use a low drop out regulator LM2490 (maplin AV22Y) and wire it up as shown on the web page. This will give you 5v. If you connect a 1n4001 diode in series with the earth pin on the regulator this will lift the voltage to about 5.7V which will probably be ok.

Alternatively there's an adjustable powersupply kit k18231A (maplin VE58N) that will do the job.

 

The above will convert the excess power to heat. To do it more efficiently you'll need a switching power supply but those are more complex DIY.

 

It uses so little power why not measure the current it takes and fit a suitable resistor (cost under 60p in Maplin) which can be wired up in a chocolate-block connector with no soldering.

 

For example if it uses 120 milliamps you would need a 68 ohm resistor to drop from 14v to 6v (hope my maths is correct). That would waste 1 watt so a 2 watt resistor costing 26p would probably do.

[Nickhlx]

It uses so little power why not measure the current it takes and fit a suitable resistor (cost under 60p in Maplin) which can be wired up in a chocolate-block connector with no soldering.

 

For example if it uses 120 milliamps you would need a 68 ohm resistor to drop from 14v to 6v (hope my maths is correct). That would waste 1 watt so a 2 watt resistor costing 26p would probably do.

 

 

... suggestion removed, as technically inappropriate ... ( too much of the juice)

 

Nick

Edited June 14, 2011 by Nickhlx

[Thewatchmaker]

I have a clock which requires a 6v power supply which I currently run off 240v using a transformer, is there such a thing as a 12v to 6v 'transformer' which I could use instead.

 

Cheers

 

Peter

Clock or Radio?

Unusual for a clock to need 6 volts especially if it's a quartz one.

Usually 1.5v with such a low drain that a small battery would power it for well over 12 months.