Yes, right Mosfet makes a huge difference. I selected the proper ones for Magnetic Pulser and they run cold despite pulsing >100A. Before they were getting warm on the heatsink. Same with my high frequency experiments.
I finally have two 711 LED panels but got busy with other projects. Beside 660nm red they also have some orange and a few blue in them. I let someone use my RLT with pen today and they noticed improvement after 30min session.
I'm ready to get this finalized except financial part.
Thanks
Vtech
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I have been testing different circuits lately. Burned out 6 LEDs (5 IR and 1 red) in the process
In order for the CC circuit to work to its full potential in a pulsed light device, all three resistances must be tuned to the LED load being driven. The three resistances being the R1,R3 and MOSFET.
I couldn't remember the details when I tried lowering the R1 value on the CC circuit so I tested again.
With 100k R1 at 4672hz 50%duty cycle a single LED wouldnt turn on. It would turn on at 73hz 50%.
I lowered R1 to 22k then 7.5k and finally 470ohm. At 470ohm the current going thru the LED was the same for all the frequencies.
As I lowered R1 the current at 4672hz got closer to the current at 73hz until finally they were equal.
At 100% duty cycle the LEDs are driven at full power, since I'm using 50% duty cycle I cut R3 in half and now have full power at 50% duty cycle for all frequencies.
The MOSFET is the IRF540(NTE2396).
Now that the circuit is working properly I wanted to confirm the importance of the lower RDS(on) of the MOSFET. I replaced the IRF540 with a IRF510 and the current dropped below full power.
Time to rebuild both the light and driver board.
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Originally posted by g.abba@live.com View PostAny dealer/builder on this -> John Bedini Schematic Kills Viruses/HIV (3 of 5) - YouTube
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Any dealer/builder on this -> John Bedini Schematic Kills Viruses/HIV (3 of 5) - YouTube
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Originally posted by Jolias View PostLight therapy based upon the red light which can be considered as infra red therapy can be taken for the inflammation of the body to cover it and settle down it by the continuous use of it normally in which electromagnetic waves are involved for the treatment properly.
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Vtech
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Light therapy based upon the red light which can be considered as infra red therapy can be taken for the inflammation of the body to cover it and settle down it by the continuous use of it normally in which electromagnetic waves are involved for the treatment properly.
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I was thinking about voltage regulator but decided to try without first. I can live with 50C and so does Mosfet. I could try different one and see if its resistance will play a role here. LED has max current 300mA @ 3V so I'm safely below that. It is 660nm 10mm dia. I have voltage regulator for pulsing chip but Lights run from 15VDC.
Vtech
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Originally posted by blackchisel97 View PostHi nte.
Pen works just fine. CC Mosfet gets warm, about 50C at lowest frequency and 245mA current. On the next setting current drops to 210mA and settles around 190mA on remaining five.
I have 230LED panel and main Mosfet runs ice cold so I decided to use 711 LED but in the same size enclosure so the LED's are mounted side by side. I used earlier pen prototype right when I built my first pulsing circuit. I got something inside my eye, right in cornea and it was bothering me for over two weeks. I guess, this motivated me to make the device quicker and try it. I took two days and three 15min sessions using 292Hz. I never had problem with this eye since and my vision - which was blurry improved and it is almost back to what it was before the accident.
All I need is to make pcb's and order enclosures. Non of which I can afford at the moment. I guess the Brain Tuner will be done before that but it was an earlier project on my list anyway. Magnetic Pulser will follow after I'll get the coils and test everything. I try no to think what next because I know it will require greater deal of funds which I don't have right now as well as more study to fully understand what and how.
I wonder who will guess what that is....
Thanks
Vtech
What was the specs on the early pen prototype?
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Hi nte.
Pen works just fine. CC Mosfet gets warm, about 50C at lowest frequency and 245mA current. On the next setting current drops to 210mA and settles around 190mA on remaining five.
I have 230LED panel and main Mosfet runs ice cold so I decided to use 711 LED but in the same size enclosure so the LED's are mounted side by side. I used earlier pen prototype right when I built my first pulsing circuit. I got something inside my eye, right in cornea and it was bothering me for over two weeks. I guess, this motivated me to make the device quicker and try it. I took two days and three 15min sessions using 292Hz. I never had problem with this eye since and my vision - which was blurry improved and it is almost back to what it was before the accident.
All I need is to make pcb's and order enclosures. Non of which I can afford at the moment. I guess the Brain Tuner will be done before that but it was an earlier project on my list anyway. Magnetic Pulser will follow after I'll get the coils and test everything. I try no to think what next because I know it will require greater deal of funds which I don't have right now as well as more study to fully understand what and how.
I wonder who will guess what that is....
Thanks
Vtech
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Originally posted by blackchisel97 View PostI finalized RLT (Red Light Therapy) pcb project and got ready for production but I'm not done with Brain Tuner yet. I was hoping to get them done this week but now looks more like the next one.
I decided in favor of slant top panel enclosure for RLT, thinking that it would be more convenient to operate this way since it is a desktop device. Same thing applies to reading frequency meter. I'll have meter, 7 pos rotary switch for all settings, illuminated power switch (instead of extra LED) and stylus socket. LED panel will be mounted on tripod and will plug into the unit from the back. Panel has 711 LED's (30W) which is twice the power and triple amount of LED of what I test right now.
Unit will house it's own 110VAC/15VDC power supply rated at 5A which is more than needed but in such way the unit could be expanded to 2 panels. All will be needed is a DC "Y" splitter. I don't know if this will happen but...just in case.
Will update when done.
Thanks
Vtech
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Originally posted by blackchisel97 View PostI decided to put CC circuit on my stylus to divert the heat from resistor into mosftet. These simple circuits are linear and not very efficient but we're not talking tens of watts being wasted. I may need to readjust the base resistance a bit. I have 10k right now. I used 2N2222 and IRF640 (what I have on hand atm).
Thanks for sharing your work
Vtech
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I finalized RLT (Red Light Therapy) pcb project and got ready for production but I'm not done with Brain Tuner yet. I was hoping to get them done this week but now looks more like the next one.
I decided in favor of slant top panel enclosure for RLT, thinking that it would be more convenient to operate this way since it is a desktop device. Same thing applies to reading frequency meter. I'll have meter, 7 pos rotary switch for all settings, illuminated power switch (instead of extra LED) and stylus socket. LED panel will be mounted on tripod and will plug into the unit from the back. Panel has 711 LED's (30W) which is twice the power and triple amount of LED of what I test right now.
Unit will house it's own 110VAC/15VDC power supply rated at 5A which is more than needed but in such way the unit could be expanded to 2 panels. All will be needed is a DC "Y" splitter. I don't know if this will happen but...just in case.
Will update when done.
Thanks
Vtech
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This is the current setup.
The Parts:
Arduino Uno
NTE 2396 MOSFET
The resistor on the left is 100k ohms. It's connected to the MOSFET gate.
The resistor on the right is 1.0 ohm. It helps to limit current flowing thru the LEDs and gives me a place to measure current flow.
6x Red 660nm 1W LEDs (350ma max).
Testing the MOSFETs:
I wrote some code to find the highest duty cycle for a set frequency without going over a set current limit. It uses one input pin and one output pin.
This worked but the resolution was really low. I ended up doing a lot of the tests by manually changing the variables.
The input is a voltage that is read at the 1.0 ohm resistor (yellow wire).
The output is a PWM with a set frequency and starts the duty cycle at zero. The duty cycle increases until the voltage at the yellow wire reaches a set limit.
During some tests with the IRF510 MOSFET, the duty cycle reached 100% without reaching the set current limit.
One thing I noticed was that at some of the lower duty cycles the analog amp meter would bounce like a SG circuit at the edge of a sweet spot.
When the IRF510 was replaced with the NTE2396 the current flow had a large increase.
With the NTE2396, PWM at 73hz with 50% duty cycle resulted in a current flow around 300ma. At a frequency of 4672hz, the duty cycle needed to be around 85% to have 300ma current flow. With the IRF510 a current flow of 300ma at 4672hz wasn't possible.
EDIT:
This circuit has many issues that can lead to burning out your LEDs.Last edited by nte; 05-28-2013, 10:12 AM.
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Originally posted by blackchisel97 View PostWhat is the resistor value going to the gate/collector? Did you try lowering a bit?
Vtech
RDS(on):
irf510 - 0.54ohms
nte2396 - 0.077ohms
I need to pick up a couple more MOSFETs and test all three strings at the same time.
Since I'm using a microcontroller the NPN and R3 resistor are not needed. If I keep the R3 it will lower the current that flows but by putting R3 to an input pin I can monitor the current and vary the duty cycle if needed.
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