AC adapter question

Your adaptor, if designed to allow the kit to work on 220v 50 Hz., should just work out of the box. I'm not sure what you mean by "exactly the same voltage and HZ specs. " Your adaptor most likely is not going to change the 50 Hz. to 60 Hz. and there is no need to do so since the AC will most likely be converted to DC.

Tom

"Tom Biasi" wrote

Thanks Tom. I mean that the adapter appears to output the same but the US mains input is obviously different from the UK mains input. I can see no reason why it wouldn't work if the output is the same and yet it doesn't. The only unknown is polarity.

Bizarrely I have come across kit (a fingerprint reader) that specifically required 60Hz and wouldn't work in the UK without a suitable inverter.

A mention of the item would help.

Graham

"Eeyore" wrote

Oh sure its called the Leapfrog Clickstart

To save you looking it says

AC Adapter Electrical Ratings: US, CAN Input: ~120VAC, 60Hz UK Input: ~230V, 50Hz Output: DC5V, 500mA, 2.5VA

What do you mean "Doesn't work"?

1. Is there any picture on the TV? If there is some Picture then the problem is different TV standards between the USA and the UK. Read the Trouble shooting Paragraph Colors/Colours are distorted on TV

or TV image is flickering

1. Does it work on batteries.

1. Is there 5 volts at the battery connector? If it works on batteries it will work if you have 5volts DC and the polarity is correct.

John G.

There are cases where the frequency of the AC line will matter, but in those cases, the AC adapter will output AC. In some cases, that means only AC, and the rectification and filtering is inside the main unit. In other cases, it means an extra contact that supplies the required AC, so the AC can be used for some clocking purpose.

But then, in the former case, the adapter will be marked as outputting AC.

The example of the latter that comes immediately to mind is the AC adapter, which was more of a brick, for the Commodore 64. It supplied

9vac in addtion to +5 and +12v, since something in the computer needed 60Hz to keep track of time.

But even in that case, the wrong AC line frequency would not result in failure, just a slow clocking.

Michael

Thats a lot of useless detail to the OP who just wants to know why his simple DC device does not work.

Of course Frequency may be important in a complex supply but this one is just a mains replacement for a dry cell battery.

John G.

"John G." wrote

yes this is just a straight case of the dc power supply. The unit works fine on batteries - just the UK version ac/dc adapter at issue.

"Eeyore" wrote

Sorry it works fine in UK on battery power. This is purely an ac/dc adapter question.

"Eeyore" wrote

Goes in the red yellow white av ports. Not that its relevant here.

"Eeyore" wrote

I don't have a US adapter - it didn't ship with a US adapter. UK one says input 230 VAC 50 Hz output 5 VDC 500mA 2.5 VA polarity symbol centre positive

Agreed!! only a mtere and actual contact with the device will isolate the problem.

John G.

"John G." wrote

Well if no-one can see an obvious reason why it wouldn't work then I might take a gamble on buying another UK adapter and assume the first one was just a dud unit. Although it seems a bit unlikely.

Well you have to measure the voltage at the connector and verify it is 5VDC preferably with a small load (less than 2.5 watts).

I guess that is difficult as you would not have asked the original question if your electrical knowledge was sufficient to do this. (No offence meant) Or get your local Computer tech to check it for you.

John G.

--
The other course, of course, is to determine whether the adapter is
dodgy.

Do you have access to any test equipment?

 
JF

"John Fields" wrote

Sadly not. Maybe I'll take it into a shop then.

This would be an excellent time to invest in a cheapie digital multi-meter. You can probably find one for under US$10 (sometimes even $5 on sale). You don't need anything fancy for this.

I use my late father's philosophy that, where feasible, it is better to invest in tools (and learn to use them), than to pay someone else. That way after the job is done, you still have the tools and knowledge for next time. And often it is actually less expensive the first time, which is probably the case here unless your shop will test for free.

Best regards,

Bob Masta DAQARTA v4.51 Data AcQuisition And Real-Time Analysis

Scope, Spectrum, Spectrogram, Sound Level Meter FREE Signal Generator Science with your sound card!