Ultracaps tested for excess energy

[PaulLowrance]

After trying a wide range or resistance, the best is about 15.5mA in and 8mA out, which is a bit over 50% efficient since the battery & UC voltages are about the same. The highest I've seen.

I'm confused about what you're saying. If the bcap & battery voltage are about the same, and the input current 13mA, and output current is 5mA, then that's 38% efficiency.

Yep. Yours is better . this is a plain Jane Jt at its worst and probably cause  i use 2 cent  china transistors .

Tried tuning the pot & capacitor together. Nothing much over 50% efficiency.

[WilbyInebriated]

Albert:

In the 1000+ pages of the JT threads, did anyone ever run a test where they compared the running frequency of the JT while changing the number of turns of wire on each of the coils?  I would not be surprised if the test has been done, but I would also not be surprised if this test was not done.

I tried to find a good link for you about this but I could not.

Don't confuse the mechanical resonating frequency of the toroid with any electrical resonance, they are two different beasts.

Since I could not find a link for you, let's discuss the transistor ON time and OF time, because that defines the running frequency of the JT.

1.  Transistor ON time

When the transistor switches on, it starts energizing the drive coil, and then it switches off after the drive coil is nearly fully energized.  The larger the inductance of the drive coil, the longer it will take to fully energize the inductor.  Therefore, larger drive coil inductance equals lower JT frequency.

2.  Transistor OFF time

When the transistor switches off, current starts to flow through the trigger coil.  Eventually enough current is flowing through the transistor base input to switch on the transistor.  The moment this happens the transistor "snaps" on fully.

The larger the inductance of the trigger coil, the longer it will take to reach the point where there is enough base current going through the transistor initiate the "snap on" of the transistor.  Therefore, larger trigger coil inductance equals lower JT frequency.

So, how do you calculate the inductance of a coil of wire wrapped around a toroidal core?

Here is the link:

http://hyperphysics.phy-astr.gsu.edu/Hbase/magnetic/indtor.html

You can see that the inductance of the coil is dependent on the size and shape of the toroid and its magnetic permeability.  Most importantly, you can see that the inductance is proportional to the square of the number of turns of wire wrapped around the toroid.

Therefore, the more turns that you wind for the trigger and the firing coils of your JT, the lower the resonant frequency of the JT.   Certainly the dimensions and permeability of the toroid itself affect the resonant frequency.

So, the most important thing to remember here is that the toroid itself does not have a natural electrical resonating frequency, but it plays a part in determining the natural electrical resonating frequency of the system as a whole.  Changing the number of turns of wire in the trigger and firing coils will change the natural electrical resonating frequency of the JT.

Notice that link is from the "hyperphysics" series, which has a great wealth of information for experimenters.  It is worth it to "drill up to the top level" from the above link to check out the site.

In my searching, I found a great technical JT link with scope shots and Spice simulations for those that are interested:

http://www.prc68.com/I/JouleThief.shtml

MileHigh

if you are so interested that you feel the need to comment, why don't you have the interest to read the jt thread? all you're doing is repeating what has been said before... show a little respect instead of pompous pedantism and actually read the thread you THINK you know all about. if you actually had read the jt thread, you would find your www.prc68.com link ON PAGE 3!!!
"for those that are interested..." good grief milehigh, those that are interested, have or do actually read the thread.

[gadgetmall]

I knew it looked familiar . Yes he not helping because the real deal is building and experiments . That tells all and there are Still unexplained territories in the Jt field being discovered everyday .

Paul  Try Different transistors like 2n3904 2n2222 2n2222a tip3055 2n3055 mps 05 mps o6 and a whole lot more have been experimented  with Including darlingtons which can output twice the current  but takes a bit more to run them . We have also experimented   or at least i have  with two transistor npn pnp and small inductors using no toroid at all . Using Nails ,washers ,wires, iron  you name it its been done all at the JT thread !. Wish someone would Compile it into a book . I would buy it  cause its some good reading when the internet fails .
gadget 

[innovation_station]

i told T to write the book perhaps she has ...

i dont know....

w

btw gadget ..  my 6 freq 555 fired fet  mac switch can go fast ...  and handle pnp and npn in sync .. and i get recovery off the relay coils ... : )

yes i have built toooooo many things ... I CAN TUNE TO 1 FUN AND 5 HARMONICS SHOULD I CHOOSE .


no limits...

i have 3 fiber nodes now ...  i can fire  fast ... should i choose ... and 25 large 1MHZ - 1GHZ RF AMPS ...

[Vortex1]

1000 pages, 1000 monkeys, 1000 typewriters.....not a hint of real applied engineering principles.

Read some good books on switchmode power design.......graduate from electronics 101