flyback arcs -IEM EXPERIENCE(01) (Ar)

The heart of the circuit is a ferrite-cored flyback transformer. There are several different types of flybacks, and any device using a cathode ray tube will contain one (this includes oscilloscopes, televisions, monitors, and others). Most computer monitors and newer televisions use flybacks which have the high voltage rectifier built in. Although a HV  rectifier is useful if you want to charge up capacitors or experiment with ion streams, having the rectifier built in is not desired for most high voltage experiments, as it will make the output half wave, and in that way make the output voltage 55% lower than it would be without it. The peak power remains the same, and adding a filter capacitor can correct that problem, but it also requires a resistor to limit the current drawn from the cap during arcing, and it is a pure DC supply, useless for plasma globes and other experiments requiring AC. The CRT on TVs and monitors is also a high voltage capacitor, and you could use it as such in an experimental HV DC power supply (covering the glass with aluminium foil greatly increases the capacitance), but a flat plate plastic cap is much smaller, lighter, and it won't implode if you drop it... Also note that the even newer flybacks out in the market today have the voltage divider and focus control built in. Some don't even have the core visible. These are useless for this circuit.

 So, overall, flybacks with built in rectifiers are still usable, but you should look for one that has either a removable rectifier (sometimes the rectifier is inside a tube that sticks out from the flyback, other times it is encapsulated in epoxy next to it. Either way, removing it is a good idea if you're able to). The best flybacks come from old TV's or monitors, specially the larger ones, and have a disk shaped secondary. Black and white TV flybacks tend to have a higher internal capacitance and higher step-up ratio, whilst monitor flybacks are pretty much useless, as far as the modern ones are concerned. If your flyback was used in association with a cascade, you can expect to obtain no more than perhaps 12kV from it (with 12V input). However, if it was free-standing, over 30kV may be obtainable (with higher input voltages). Nominal output current is 1-2mA, and arcing current can be as high as 10mA and above (mine can melt a steel sewing needle!).