I am building an alarm circuit and need an autotransformer to step up the voltage powering the pizo sounder. Trouble is I can't find anyone who sells the aurotransforners. Any one know where to get them.
the auto transformer will up the voltage to give more volume to the pizo (the louder the better) it is also smaller than a traditional transformer. and cheaper (if I can find a manufacture) The voltage will be up to 12v from car battery and a backup battery of maybe 9volts.
I don't see why it would be smaller than the isolated version?
The Va would/should be the same?
If this is high frequency, try the pulse transformers from Hammond, DigiKey etc.
I am building an alarm circuit and need an autotransformer to step up the voltage powering the pizo sounder. Trouble is I can't find anyone who sells the aurotransforners. Any one know where to get them.
I would imagine they are custom made for the manufacturers who use them, and probably not available 'off the shelf'. As already mentioned, there's little reason for such an auto-transformer to be much smaller or much cheaper - essentially all you save is the length of the primary on the secondary, and if you wire the isolated transformer as an auto-transformer you will get a higher output anyway.
Why not just buy a sounder that contains the oscillator as well as the transducer ? Most of these devices just need to be supplied with DC (Normally 12 volts,) This is one example