John Urbanowski Amazing Radiant Battery Charger

[gyulasun]

Hi Groundloop,

would you mind checking the following:

In the hand-made drawing uploaded by gotoluc in his first post (and also in Sephiroth's drawing) the not-grounded leg of the 1uF capacitor  goes directly to one of the relay contacts (this is ok in your drawing) then goes also directly to the diode's anode and not to its cathode.

It comes from this that the relay contacts discharge the 1uF any time the relay is on... but hopefully the 1uF does a good service during the relay off time periodes.

Re on the transistor type: gotoluc included a 2SC1768 transistor type in his first post.
Also some info on the coil core is there (probably PVC insulated iron wire pieces bunched into the coil former)
Also some wire gauges are mentioned.

Thanks
Gyula

[gyulasun]

Hi All,

the 2SC1768 is a discontinued type, though it is still available from some retailer. It is a 200V, 5A, high current gain NPN transistor

Here are some data on it from here http://www.datasheetarchive.com/data/2SC1768.html

2SC1768
  Si NPN Power BJT
   
V(BR)CEO (V)=150
V(BR)CBO (V)=200
I(C) Abs.(A) Collector Current=5.0
Absolute Max. Power Diss. (W)=50
I(CBO) Max. (A)=1.0m
h(FE) Min. Static Current Gain=400
h(FE) Max. Current gain.=3.0k
@I(C) (A) (Test Condition)=1.0
@V(CE) (V) (Test Condition)=4.0
f(T) Min. (Hz) Transition Freq=15M
Package=TO-3

A good substitue seems to be 2SD1090, see here http://www.alldatasheet.com/view.jsp?Searchword=2SD1090

its package which is different.

rgds,  Gyula

[Groundloop]

@gyulasun,

I have updated the circuit drawing. There is still issues. I think the relay is closed
in one position when the transistor does not control the relay on. It must be so
because the oscillation will newer start if the relay is open in the middle.

Also, the capacitor seems wrong in this circuit. It will be shorted out every time
the relay closes.

Any thoughts?

Groundloop.

[gyulasun]

Hi Groundloop,

Thanks for the correction, though I don't think it is finished either because gotoluc wrote in his first post:
I asked him to make a hand drawing of his main circuit he used in the video and it is below. One thing to note is he has 2 extra coils he added to tone the circuit which are not in the schematic. We will give the details on these but the circuit should give the general effect as per schematic.   so some more corrections will surely be needed when we learn about every detail.

Yes, I agree the oscillator cannot start when the battery voltage is present on the transistor...  John Urbanowski in his video starts the oscillator by saying it but not showing what he does,  probably he pushes down by hand the armature of the relay to close the normally open contacts for a moment...

Re on the closing of the 1uF cap: yes I already mentioned this, it is strange he dissipates the energy stored in the capacitor in the contact areas of the relay...  When the relay is off, this capacitor charges up to the battery voltage of 14V and the relay does two things when switched on: it discharges this capacitor via its closing contacts and at the same time connects L1 (1000 turn coil) to also the 14V battery voltage. Now when the relay gets off again, the current is disrupted in L1 and the part of flyback pulse should go to the 1uF cap and also part of flyback pulse goes to the 24V battery as charge current via the diode. The difference between the flyback peak and the 14V is that is able to charge whenever it is >24V...  Then this repeats as the oscillator works.  Please comment if think otherwise.

rgds,  Gyula

[gotoluc]

@gyulasun,

I have updated the circuit drawing. There is still issues. I think the relay is closed
in one position when the transistor does not control the relay on. It must be so
because the oscillation will newer start if the relay is open in the middle.

Also, the capacitor seems wrong in this circuit. It will be shorted out every time
the relay closes.

Any thoughts?

Groundloop.

Hallo Groundloop,

thank you once again for your great help here

I think he is using only one side of the relay to switch!  I will confirm with him today to see if it is the NO or NC side he uses. I will ask about the capacitor position and also confirm which side the pots are on.

Here is most of the information you asked for main coil, core material, transistor, relay and Capacitor

The main coil is wound on a (empty) plastic wire spool he had. It has a 1" = 25.4 millimeters core opening (hole) and it is 3.5" = 88.9 millimeters long and coil is about 3" = 76.2 millimeters in diameter once finished winding. His trigger coil is wound first on the spool with 26 gauge mag wire which is 75' = 22.86 meters long. The roll is available from Radio Shack in a set of 3 assorted rolls, it is the green roll he used. Then wound over top is 1,000 turns of 19 gauge mag wire. The 1 inch core opening of the spool is filled with cut strips of plastic coated Iron wire used construction to tie metal re-bar together. The transistor is model SC1768. The relay is an automotive 30 amp to which he opened and uses a set screw to tune the pulse. He also has a ceramic magnet to help tuning. The capacitor is 1uf microwave oven capacitor  which are usually rated at 2,500 vac.

Thank you.

Luc