Another "TEA" laser - a solid state one being packed into a box from tea. Its base is very classic "SSY-1" laser head. Plus a pair of electrolytic capacitors, charger for them and ignition system. The thing also contains a small green laser pointer used as a guide laser (aimed through the SSY-1's resonator). When i tried to use red pointers they died quickly due to leaking beam behind the back mirror. It forced me to use green pointer and a piece of blue glass as an IR filter. The toy appeared to be nice and very handy.
The discreet charm of stirling engine can enchant even a laserist. I won't put here a link to a guide how to make it. Anytime You can google up for the words "stirling engine" there are tons of them over the net.
Probably the World's Smallest Lamp powered Homemade Dye Laser. Its active length is 30 mm, its resonator length is 75 mm (mirror-to-mirror). It can be held on a palm together with its pulse forming network. Its storage bank has only 6.6 nF of the capacity that means as little as 1.3 J of the electric energy @ 20 kV (comparable with the typical energy stored in the wings of a common TEA nitrogen laser. The spot is large and brigt. Maybe 50..100 mcJ by my visual estimation. It is simple and works good. I think it deserve a guide after some more experiments.
The same tiny laser operating handheld powered by a small stungun. It's placed upon a lid of a plastic jar to preserve me from being electrocuted. Note that the storage bank (and voltage) have been halved here. Only 660 mJ in the main storage and it still lases! If one can invent a tiny liquid pump for this thing the way to the DIY yellow laser pointer becomes open.
The same laser with fully homemade capacitors. As You can see it became smaller. The right botom photo shows peaker flashover - too compact means electrically weak.
If somewhere there is a high voltage, sooner or later there will appear a lifter (aka EHD thruster). Simply looking but not so simple to create. Weight is its enemy. This one was made of three juice sucking pipes. They took out 1.6g. So only one gramm was left for all other equipment (props, threads, foil). After several attempts it finally went up being fed by my 30 kv common laser power supply. Some people claim that the lifter flies due to electrogravitic effect, others say that it is ionocraft. In any case the excellent experiments by J. Naudin show our lack of knoledge about the nature of lifter's thrust.
Copper Vapour Laser (CVL) (Video)
Not lasers only... Recently I've helped somebody to tune... A jet engine. Not more not less... It was a so called "Thermojet" - valveless pulsed jet engine. Fully homemade (tin can as a combustion chamber and epoxy textolite tailpipe and inlets) followin Beck Technologies blueprint. The key to set it right was to make fuel injection nozzles having the orifices 1 mm in diameter (the detail humbly not mentioned by Beck). With those fuel nozzles the Thermojet operates stable using gas propane either directly from the tank or through a pressure reducer. Measured thrust is feeble however - abt 1 lb. Ive got some ideas how to increase the thrust keeping the size of the engine at present level. More on this later...
Nano SSTC - very simple device, consisting of square wave generator + mosfet driver (UCC37322) + IRF460(letterless) + the coil itself, gives very nice
sparks... srry... brush discharges. The combination of radio frequency and smoothly but fast rising envelope allows to make discharge by an order of magnitude longer than it could normally be. The low voltage part is powered by a small 9v batterry, and the MOSFET is fed by a capacitor having been charged from the mains.