This DIY portable HV DC source. Consists of four main parts; a power source (AA bat), a camera flash, and a multiplier. Simple to construct. Output is ~4kV DC and is quite painful.
Modify the camera flash to obtain just the inverter circuit. Each flash with be unique however. Remove the xenon tube, trigger transformer, and capacitor as shown.
Inside blue lines to the left is the part of the camera flash that is used. Remainder can be removed. After cutting was finished the result is pictured below.
These are what I used to make the cascade multiplier. 33nF 250v capacitors and 1000v 1A diodes. My suggestion is to use low value capacitors to keep the charge time to a minimum. Single stage completed to the right. White stripe is cathode.
Capacitors placed too close arc through the insulation. Completed multiplier shown below.
Purchased a small project box and installed internals. I used two screws were used as terminals, they work quite well.