Quote from: Lidmotor on July 09, 2018, 12:55:50 PM
Gyula---Your comment, "Each oscillator has it's own soul."  is so true.  This latest G. Bluer circuit is no different.  Gary builds weird circuits---always has and he doesn't explain much in his video.  To me they are puzzles and going back many years I have enjoyed them.  His 'Slayer Exciter' like the Joule Thief is a classic.  This 3 choke exciter is a 'tinker toy' and meant to be played around with.  I did get the original circuit to run but quickly modified it (like Slider and Gary are doing).  Mine does not self start so I am using a BBQ lighter spark near it to jump start the oscillator.  I eliminated the 1M resistor.  Here is a tip: Just take two chokes and put them side by side and wire them up to the NPN in a regular Joule Thief circuit.  If you get good led performance like that you know that the chokes and the transistor like each other OK.  If that works then it is just a case of reconfiguring the two chokes into the new circuit.  The third choke can be replaced with a Slayer Exciter tower if you want and the cap doesn't do much I found.  Keep the 1n4148 diode and led going from the (-) to the base for this thing to run right.  I'm am not seeing the super low amp draw on mine that Gary shows but it will run down to about .6v.  Any 2N2222 type transistor works fine. Stay under 4v to keep it alive.

All--Dr. Stiffler's latest video is about using three coils resonating together ----driven by a function generator.  I think I know why he is doing this and where he is heading.  Remember these days?  Guess what that 'special frequency' is that he talks about in this video from 2011.
https://www.youtube.com/watch?v=7lbYjqU48Mw

I wonder if he had his function generator (set at that 'special frequency) connected to something near that AL block sitting on the far right side of the elevated board?  Hummm.

Even if this device was not 'self-running',as people thought, to me the fact that it worked at all is amazing.  Now that I have a signal generator perhaps I can replicate this experiment.  I always thought that perhaps he just had another SEC running near by ----but what if it was just his signal generator broadcasting at 13.6 Mhz pumped out at about 1 watt.

----Lidmotor

Lidmotor,

thanks for pointing to this old video, he seems to be going in some specific direction.
Thanks also to RAMSET in the followup post for the link to the latest Dr. Stiffler video here:

https://www.youtube.com/watch?v=lxRbckLedjU

I tried to replicate this setup/test and build me 3 L3 coils (16mm diameter former, 72 turns)
which measured to be 26.7 (2x) and 27uH.

I put the 2  26,7uH coils on a wooden rig so i can change the distance between them (allthough that
seem to have little influence on the leds output).

Using the FG at first, set at 20Vpp, sine wave, 13.6Mhz and using the red lead only.
Input to the first L3 coil goes via a 1 Ohm csr to take some differential measurments.

Screenshot shows the signals across the 1 Ohm csr (blue input side, purple output side, red math function Blue - Purple).

Video about this test here: https://www.youtube.com/watch?v=gEhW7oQyHrA&feature=youtu.be

I see very little or no difference in signals across the csr meaning no additial load (current) seems
to be drawn from the FG with the L3/leds combo inserted and lighting the leds (rather dimly).


Itsu

Itsu - Good point about the crystal frequency, thanks for the pointer.
Am using a C3198 in the circuit, broadly similar specs. The 3904 is a bit faster but the C3198 is 80MHz rated. hFE is more on the C3198 which could factor for the Base components. In fact, i'll just swap in a 3904 and take that bit of the equation out !
Will swap out the crystal for lower values too

Hi Slider,
Try to connect a choke coil of about 47 uH to 220 uH in series with the collector resistor, this will enhance amplification factor at 13.5 Mhz.  The 4.7 k to 6.8 kOhm in the collector have much less values at that frequency than at the lower frequencies, with the series L the AC impedance increases on which the transistor can amplify.   

What DC supply voltage can you assign for feeding such voltage amplifiers?  What is the maximum DC output of the step up DC converter you have?
Gyula

Itsu:  Glad to be of some help with the original L3 coil specs, I appreciate all of your efforts and the good work that you share.  You and Gyula (excellent knowledge and patience) provide very good technical info
to learn from in your back and forth team effort.  Thanks to you both, I'm sure there is much more to be learned here.

Gyula - yes, thanks so very much for your continued insights. I'll certainly try the inductor.
Thinking about this, Lidmotor made reference to a regular Dr. Stiffler wound L3 being approximately 100uH...could that be used ?
Am guessing that there wouldn't be an advantage of it over an axial type though in that spot.
Output of the booster is 15V, it can go up to approx 30V.