I´m new at the transformer construction, so if anyone can guide me will be nice.
My target is a step up transformer, ratio 1:10, for 1KHz to 10KHz operation, and 5W power. Input voltage is 9V square wave... desire output 90V squarish wave...
Or if some one know a model of transformer that already do this, please let me know, haven´t found it yet!

Thanks!

 

An inverter transformer from one of the hand-held fluorescent lights might get close on wattage, but the voltage would also probably be too high. Model ignition systems usually boost 4.8 V to around 300 V (20:1 turn ratio, approximately). Edit: I used 32 to 38 AWG for the primary. The wire size in that range is not too critical. The main limitation is space. Anything smaller than 38 gage gets hard to wind.

I have made a few for ignition systems using a powdercore toroid and about 350 to 400 turns on the primary. It is boring work for about 2 hours, but not difficult. The trick is to make a shuttle like used in weaving for winding the toroid. If you are not restricted to size, use a larger core about of 20 to 25 mm O.D.

The easiest way to wind one yourself is to simply use a bobbin from a E-core or half-pot core, but finding the cores may be a little more difficult. Some modelers have used the cores form small audio transformers for that purpose. John

Edit: A simple 120 to 12V step-down transformer (or similar at 220 V with center taps) with the secondary wired as the primary might also work.

 

Thank you very much for the reply! Will test, and let you know how I did! I have some Old HP-PDA that is not working anymore, so will take out the parts too to test!