AC Adapter

machine?

If it's unregulated it will have a higher output voltage.

Greg

What device is this adapter powering?

Assuming DC, no problem if your unspecified device does not require regulated power. Some power supplies have internal regulators. This is very common with 5.0VDC adapters. Not so common with 12VDC adapters, but still possible. If your adapter looks and feels like it's just a big transformer, with just a diode inside, the replacement is fine. However, if it looks like a switching power supply or the unspecified device lacks an internal regulator, you'll eventually have a problem with an unregulated adapter.

If AC, there's no such thing as a regulated AC wall wart so there should be no problem substituting a high power adapter.

If DC, also, check the polarity on the DC power connector. Panasonic phone devices and computah powered speakers sometimes use positive grounds.

If DC, I usually don't have many failures with transformer operated AC adapters. If they get hot, they may blow a thermal fuse, but that takes real effort. However, switching regulators are another story. For example:

They're smaller, lighter, more efficient, cheaper, and turn off without a load, but fail far more easily and more often.

have several 12V 1000mA. Any problem using 1000mA rated unti with 225mA machine?

Based on your question, the short answer is NO!

The longer answer is.... What is a machine? sewing machine? machine gun? gumball machine? Pinball machine?

Replacing an AC adapter with ANY DIFFERENT AC adapter often works...except when it doesn't. There are many subtle differences that CAN matter.

The fact that you asked the question suggests that you don't understand those subtle differences.

Cheap devices are carefully designed to balance the output of the supplied adapter against the needs of the device. Are batteries being charged?

More expensive devices are often more robust, but I once had a $2000 Compaq laptop computer that used the current limit in the ac adapter to set the battery charge current. BAD DESIGN, but there it was. Using a different adapter was a disaster...ask me how I know.

Nobody can help you decide without more information. Any advice you get based on your supplied info was made by someone guessing.

gregz wrote in news: snipped-for-privacy@news.eternal-september.o rg:

and watch the plug polarity. some wallwarts use a positive ground DC plug,others use the usual negative ground.

Another question.... I have a radio that shows a 9VDC input. Would an = adapter with 12VDC output work?

adapter with 12VDC output work?

I have a radio that shows a 6-12 VDC input. I would use your 12VDC adapter with that.

Too high a supply voltage (Volts, V), smoke from the apppliance. Too high a demand for current (Amps, A), smoke from a puny adaptor.

Find a 9V DC adaptor that will supply at least the rated current the appliance requires. Given that this may vary dependant on the volume the radio is played at, and you don't know the radio's design limits for max/min input voltage - best choose a adaptor that has a built in voltage regulator (as suggested by gregz). Normally this is stated on the case.

adapter with 12VDC output work?

Not likely. It will damage the radio if it doesn't have an internal regulator, which is rare as hen's teeth.

the=20

The problem is it's a telephone/ans machine I brought back from Japan = and all the printing is in Japanese. Original adapter was lost. No = voltage/current numbers printed on the case anywhere - only says "DC" = next to the plug. Searching the Pioneer website and elsewhere I could = not find any data or info online looking up all the model, serial, etc = numbers. Markings: TF-V21, A99-1185JP and their phone numbers =

ividual.net...

all the printing is in Japanese. =A0Original adapter was lost. =A0 No volt= age/current numbers printed on the case anywhere - only says "DC" next to t= he plug. =A0Searching the Pioneer website and elsewhere I could not find an= y data or info online looking up all the model, serial, etc numbers. =A0 Ma= rkings: =A0TF-V21, A99-1185JP and their phone numbers 042-949-5131 and 06-6=

The TF-V21, although apparently obsolete, is listed on the Pioneer web site as a device that will operate in case the power goes out. Therefore, it will operate from one or more batteries. I would open the case and see what sort of batteries it uses.

It's amazing what can be learned given google search and google translate.

I don't know about the USA but the rest of the world has largly moved to regulated SMPS for small device wall warts. And they generally even suport the USA voltage too (Wot is it 120 volts) ;-)

Conventional external power supplies using bulky 50/60 Hz line transformers have largely disappeared, as the parts used in switching supplies have become less-expensive.

Most products come with tiny high-frequency supplies that are not only regulated (regulation is a native feature of switching supplies), but will work on any line from 90V to 250V. This allows the manufacturer to have a single inventory. The same supply is shipped to every country, with only a simple plug adapter (where needed).

Most newer warts are SMPS, but if its one that's salvaged from older equipment that's not likely. I have over 300 used warts, and only a few are SMPS. I have about 100 laptop/printer 'desktop' supplies that are.

adapter with 12VDC output work?

I wouldn't as a 12V unregulated wart is often 15-18 Volts unloaded.

to regulated SMPS for small device > wall warts. And they generally even s= uport the USA > voltage too (Wot is it 120 volts) ;-) Conventional external= power supplies using bulky 50/60 Hz line transformers have largely disappe= ared, as the parts used in switching supplies have become less-expensive. M= ost products come with tiny high-frequency supplies that are not only regul= ated (regulation is a native feature of switching supplies), but will work = on any line from 90V to 250V. This allows the manufacturer to have a single= inventory. The same supply is shipped to every country, with only a simple= plug adapter (where needed).

FWIW, I have found that many 'compliant' SMPS 'wall warts' cause severe rad= io interference on the BC band and SW bands, but much less so on the FM ban= d. Conducted and radiated emission standards for these units are generally = fine unless they are connected directly to a receiver [where the PSU is eff= ectively in series with "Ground" ].

Neil S.

To power a cb radio, I had to add 3 more ferrites plus extra turns through them to get acceptable results. To get low capacitive 60 Hz feedthrough, you need to ground one output leg. That was necessary when using audio or medical devices.

Greg

messagenews: snipped-for-privacy@mid.> > > Another question.... I have a radio that shows a 9VDC input. Would

the

on

and all the printing is in Japanese. Original adapter was lost. No = voltage/current numbers printed on the case anywhere - only says "DC" = next to the plug. Searching the Pioneer website and elsewhere I could = not find any data or info online looking up all the model, serial, etc = numbers. Markings: TF-V21, A99-1185JP and their phone numbers =

The TF-V21, although apparently obsolete, is listed on the Pioneer web site as a device that will operate in case the power goes out. Therefore, it will operate from one or more batteries. I would open the case and see what sort of batteries it uses.

It's amazing what can be learned given google search and google translate.

Thanks for that! I it has been used for months now with no AC. Will = check it out and post what I find out.