Step down or Step up Transformer

Feb 24, 2004 51 Replies

Oops - brain fart! - yup you are right I was thinking "inversely proportional" which is of course a capacitive reactance.

(note to self - engage brain before posting in the early hours of the morning!)

Yup - go along with that... the main issues are not technical.

Wall warts are available from places like Maplin, or CPC etc. They start at under 3 quid for a cheap unit that will give DC at upto 12V and

300mA. A better "regulated" unit (say a fiver at CPC) would probably be better since it will have less ripple on the output and be less likely to introduce hum into the audio.

Cheap basic variable voltage unregulated:

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if that wraps:-
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a better fixed voltage regulated unit:

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Yes, thankyou. My failing argument has been pointed out, I stand corrected, try reading the whole thread before posting. ..

SJW A.C.S. Ltd.

Plus, you will have enormous trouble finding a 110 -> 240 transformer in the US. They probably don't realise that there are any other kinds of leccy in the world.

Guys

Some of this conversation is going over the top of my head! I got the specs for the phone -

"Charger # 5864200W11 120Volts with an output of 9 volts DC 700 mA. This cordless unit has a very small fuse that is set to pop for your own safety; they mentioned that unless you end up buying a high end expensive power converter transformer, it will most likely continually pop the safety fuse. "

Comments please.

Go to

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and look at item no. VN10L. That'll do you nicely. ..

SJW A.C.S. Ltd.

Other than the fact they use 240 in the US for large appliances such as Tumble Driers and Washing Machines etc.. ..

SJW A.C.S. Ltd.

Apologies if it is a basic question but looking at the Maplin product I can see the 9Volts but where is the mention of the 120volts and

700mA please?

If you're using it in the UK you don't want 110v, thats the input voltage. You want 240v, which that one is. The 700mA is the output power, the one in Maplins is rated at 1200mA, this is the maximum power available from the power supply so the extra isn't a problem. You could look at the 700mA as the minimum you require. ..

SJW A.C.S. Ltd.

Thanks a lot for the reply. Last question - will this be ok for continuous use i.e. the answer machine phone will be plugged in all the time.

Yep. I've got a couple of similar cheap ones doing continuous duties and they've been fine. ..

SJW A.C.S. Ltd.

Big deal. Your post *was* the whole thread when I posted. Admittedly google is probably the slowest to update, but just because you can see follow ups on one usenet server, you can't assume that they can be seen on all other servers.

No they don't. It's 220 balanced. IOW, two 110V lines.

I knowed it weren't 110V though, so I wasn't far off! ..

SJW A.C.S. Ltd.

ZZZzzzzzzttttt!!!!!

Silence. Darkness.

"I knowed it weren't 110V though, so I wasn't far off!"

Famous last words. :o)

[T] So, Dixons it is then!

All the best ..

T i m

The 9 volts is the output of the device. The input to that device only has to match that of the country it's being used in. In the UK this is assumed to be 230 volts, so won't be mentioned in the spec.

However, your device says it is a charger. That's a different thing from a power supply.

Haven't you missed the fact that it's a charger - not a simple power supply?

Where did you get that from? I can't see any mention of charger. Are you sure you're looking at the right item? ..

SJW A.C.S. Ltd.

US has been 120V since sometime in the 1950's (or

240V for two 'hots' circuits).

Some States have dropped their nominal value to 117V to save power in more recent years.

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