Hi Gary,

Keep up the good work.  My favorite part of your setup... "An output coil consisting of 1.15 kilometres of 0.25mm copper magnet wire, this coil is on a separate former that is larger than the drive coil's former and so can be placed around the drive coil."  Hehehe  Good to see someone is listening and actually grasps some of the concepts I have learned and spewed out from SM.  He said one would be suprised how much energy can be extracted from a magnet, based on the very principle you have used. 

Cheers,

Bruce

@Gyula

Hi. I can't get hold of a 7818 tomorrow, i think this one will do please tell me if i am correct :

http://www.maplin.co.uk/media/pdfs/Module%208067-2.pdf


Thanks,

Gary.

Hi Gary,

Yes, this IC (http://www.maplin.co.uk/media/pdfs/Module%208067-2.pdf )  is also fine to use, another  make of what derricka just suggested.

NOW that I have seen your setup, please do a favour for yourself: check the current consumption of the 0.15A from your 18V power supply WHEN your 220 Ohm load resistor is connected to the output (unless you have done so already).

There is one more problem: as I tried to estimate the power loss in the 7818 voltage regulator (it will be the same for the TS317 too) it comes out too much loss and it eats up your COP to under the value of 1 so looping would not work....   Think it over:
your input power is 18V at 0.15A=2.7W (assuming you measured this when the 220 Ohm is actually across the output)
power loss in the 7818: 10V at 0.15A=1.5W
output power in the 220 Ohm as you calculated: 3.82W

Now 3.82-1.5=2.32W and already this is under the needed 2.7W input power.   SO one solution is NOT to use the 220 Ohm when you are looping, not to use even the 350 or 400 Ohm what I suggested last night, then the dissipation might just be enough for a COP of just over 1....

Gyula
 

EDIT: possibly your unloaded output voltage is higher than 40V which is the limit for the TS317 or LM317 max input alloweable so make sure not to exceed this, otherwise you burn the regulator IC....  use preloading just under 40V output first , then connect the regulator IC and make the looping for a moment and check always the voltage level across the regulator input, assuming you first built already it to give out 18V.

Can't get what i need locally, have to mail-order


Gary.