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Just because you can doesn't always mean you should.
Why don't they stick to pondering mousetraps?
Blackhat
Bad experiences come from poor decisions. So do good stories.
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I keep life simple and just try and use the old and boring 120v lights. I tried those little lights many years ago- no more, unless I am prepared to throw them away when they quit or it is a gift to someone I don't like.
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I would be curious about what kind of light bulb works on 20kHz AC as well. The frequency change implies an inverter, a transformer can't do that. As someone said above, something like a VFD. 120Hz AC->DC-> 20kHz AC This type of device usually doesn't work no load, they usually require something like 20 percent load. Costs more to get one that works at no load. And you probably do need a true RMS voltmeter to read it, the cheap ones use some kind of hackery that probably only works at low frequency.
Other than replacing capacitors, I've never had any luck at repairing a device like that.
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While they dont need 20khz I would think any regular bulb would light. A transformer for higher frequency requires far less iron than for 60 hz. The transformer can be made smaller and lighter for this reason and probably cheaper.
Like blackhat said just because you can does not mean you should. I was wondering on the other fixtures where the bulbs work, do they have this type of transformer ? Roly
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I can't entirely answer your question. I do know that a non-RMS meter will get pretty close to the true voltage reading from a normal 60hz power source, such as your wall outlet (RMS may read a more accurate 122V while a non-RMS may read 117V or something like that) but if there really is a high frequency output from that device, then it may be that your non-RMS meter will not give you a true reading. One place you may go to for electrical advice is EEVblog.com. Click on the Forums and you should be able to find a forum to ask your question on. You will have to join the site in order to post, though.
If you're willing to get a new multimeter, the Uni-T UT-61E seems to get the best "bang for the buck" nod from many electronics folks there and on other electronic forums. It can be had from Amazon for less than $50 (perhaps even much less now with Black Friday sales going on) and has been shown to be very accurate (search You Tube for that meter designation and you'll find a bunch of folks who have tested them), and is True RMS.
Like others, I suspect you have a bad transformer, especially since your meter is reading much lower than the output should be plus it will not light the light it should.
Paul
Paul
They were right, I SHOULDN'T have tried it at home!
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(11-21-2016, 06:26 PM)sroxberg Wrote: I bought a Transformer that is supposed to take 120AC and convert it to to 11.6 V output.
My multimeter a Gardner Bender Digital Multimeter DGT-311 reads the output at 3 volts.
The transformer has the following statement/warning.
High Frequency output is only readable with a true RMS meter, with sufficient range capability.
My meter is a $30 dollar unit so I'm assuming it is not RMS.
Would I get no reading, or is the 3 volts a sign that my meter won't read the output, or that the transformer is defective and isn't putting out 11.6.
The light that this is supposed to light up does not work.
Get an Oscilliscope, then you'll know what's coming out of it.
