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Registered Member #941
Joined: Sun Aug 05 2007, 10:09AM
Location: in a swedish junk pile
Posts: 497
I have two GT15Q101 15A 1200V IGBTs that i pulled from an old ups that i dunno what to use for, voltage is a bit high and current a bit low for anything audio related.
I've considered something like a inverter to turn 230V 50Hz into anything up to 400Hz or a low power induction heater of some description or just some boost dc/dc converter that could turn say 12V into something like 500-1000V DC or a APFC circuit.
I also got four IRFP150's from the ups and those have already been set aside for a stereo class D amp project.
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4059
Yes, a digital amplifier based on PWM would be a whole new class of coolness. Apparently this doesen't harm the speaker which is far too slow to reproduce anything more than 20 kHz so if you use 100K (or to be nice, 125k) you can also charge up stuff by placing it near the speaker coil(s).
The WiTricity wireless chargers use 13.56 MHz I believe, however you will get in deep schist if you use this band because it interferes with doorbells, RF car alarms and wireless meeces among other things.
Best way to tell is to examine the coil used, if it only has 10 turns it is likely to be in the MHz band.
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In need of inspiration
