Thanks Bill . the hard plastic is An "Audio Amplifier" . it a stiff piece of plastic touching the top of the C-core . the c core has two ferrite c shapes that go thru the middle and top of this transformer . It will  Screech and scream if not glued together . It's loud and buzzes like a Buzzer . the plastic amplifies that sound and it is deafening loud . Thats why i called it Joule Screamer No the 3055 will run to less than .3 volts .. I have no idea how many turns are on it cause pulled it from a circuit board . i would estimate about 30 or 50 turns on each side . its wired with the basic Jt wiring . i just used this c core and a 47uf cap across a 9 k pot . Doing a time run on it and it's going dead dead now at .345 v. the c core Vibrates where it comes together .thats why you see them glued and taped at the top in power supplies..If you set this thing on a smooth surface it gets louder and vibrated off the surface like a cell phone vibrator motor .

sorry double post .. dam quote thing is messing me up .

if you want to build this i used a standard jt hook up only instead of a 1k resistor replace with a 9 k pot and place a small electrolytic cap across the outer legs of that pot .the cap i used is 100mf@50v.i thought it was 47 until i got out the magnifiers (eyes getting bad) the center would go to your base and pick one outside leg to a coil .This will make your jt pulse variably. mine clicks one click (blink) per second and goes very high until it reaches the transistor frequency and coil frequency and then locks and stops oscillating but the core is also locked tight together by magnetism  so the circuit is still energized /  these c cores are also in old power supplies . I tried to pull one apart and the brittle ferrite crumbled and broke But some of them are not glued and have a stiff springy metal cap on top of them that you can pull off and the cores are not glued together . My latest video shows a piece of copper strip formed to fit the top and amplifies the sound . It also wiggle and moves but i don't think you can see it with my camera phone .
This Joule Screamer will not measure on any of my meters , it shows the same dc volts as the battery voltage 1.2 volts or lower. Nothing on the ac side that is negligible.like .068 to a bit 1.3  . very strange . even tried to put a diode on one leg and it still reads the battery volts .It has to be higher than 1.2 volts to light just one led and you would think much higher to light a 110 ac unmodified LED bulb. Radiant?


here is the first vid http://youtu.be/zA-7yc0J2XU
new video uploading showing volts . and maybe wiggle of copper strip .
just a thought . The motion of the copper strip might be a prime mover for piezo element to generate more juice / it is also aiding in producing a second harmonic mixing with the first one . the frequency changes not only by the pot but by the distance of where the c cores meet and this is a random variable by the top of the copper strip grip .I would think this is a form of Flux Displacement in the core.The rattle harmonic was by accident  in discovery and i think it can be harnessed for power.What i would do with this power is store it then bleed it back to the input side.
One last note is this design has advantages over a toroid in that it has a gap that is moving by magnetic force .motion and magnetism  and pressure you can see and feel .
gadget

Joule Screamer volts video     http://youtu.be/gr5yztVOnTY

this time i got a range on ac to 1.3 volts but slightly lower on dc .Doesn't explain why i don't see the voltage to light leds ..especially a 110vac bulb
It Could be the frequency is higher than a digital meter can read . but still at a lower pulse it is low on DC even with a diode reading.

Well i am a little sad at the activity on this board . It has vanished. I regret leaving for years and miss the backbone crew who built,tested and interacted . If i didn't say thank you to some then i will say it here being this thread is dead . Thank you Bill,MK1,Jeanna,Kooler,jonneydavro,Willeyinebreated,Xee,groundloop and all the other builders i forgot their names for some exciting inspirations . If not for you nothing would have been interesting or progressed to a higher  level. SOme say it's all been done before and it's just a blocking oscillator but NO we took it further than anyone and taught others how to do it . The Internet is 1000's of time more info on Jt's that when the first JT by Clives was built and named because of your research ! It's the builders who are the Smartest not the mathematical trolls with meaning less quotes from a one handed mind.

I applause you and miss you but i understand why you are gone also .

Gadget .