Help cant get homemade toroid to work

ian field

Joined Oct 27, 2012
6,539
Lol lots of replys wow...lol
okay yes the bare wire is insulted.
Yes I did burn enamel off and sanded it down.
yes the mains where connected when I tested it.
.178Ohm 24g .4978ohm 30g

So after I posted this about ten mins later I did get a reading at least. 19.8vdc in currnet draw-2.89347amps. Output 60hz at .0096vdc steping up and .0087vdc steping downsame current draw.. and yes this drops my input voltage to the same as output. So im guessing I need much higher freq.

Can any of you link me to a simple dc chopper schematic. Possibly using a 555. If you guys think freq is my prob.

So yes possibly need higher freq.?
The all out simplest is a blocking oscillator. You could use the 100T winding as the collector load (more turns would be better), put on a feedback winding of about 15 - 20T. If you were running off single cell 1.5V, you could return the feedback winding in series with a few tens of Ohms to +v - with higher Vcc, you have to ground one end of the feedback winding and AC couple it to the base with a capacitor, you also need a start up resistor from base to Vcc - about 100k should do. If it doesn't oscillate straight off, reverse the phase of one winding.

You should get flyback pulses at the collector, quite a few times bigger than the input voltage. You can wind on a secondary with more or less turns than the collector winding, depending what voltage you want out.

Some of the chip manufacturers do tables of chips by type, you can usually find a SMPSU control chip section - gather some type numbers and look into their main properties. Usually you can get a data sheet and some application notes with circuit examples.
 
Output 60hz at .0096vdc
NOTE: Emphasis added...

While asymmetrical output is the rule with 'energy storage' (e.g. flyback) topologies, it is inconsistent with the described implementation ---- If the above quoted text is not a 'typo' please measure the secondary EMF with your DMM set to read AC -- Or, better yet, a scope...:)

Best regards
HP
 
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