Led phototheraphy circuit

While doing a research across the web, I notice the topic about phototherapy. It says that exposure to a light at specific wavelength is beneficial to human body. This light may come from various sources such as sunlight, lasers, lamps and Light Emitting Diodes (LED). According to some studies (just read more about this on the web), that exposure to light can cure some skin disease, wound healing, hair growth, and many more.

In relation to that phototherapy idea using LED, the simple circuit below is a led driver powered by a single 1.2V or 1.5V cell. Since the voltage from a single cell is not enough to light up the LED, The circuit steps up the voltage that is enough to light up the LED (see more about the forward voltage in LED info). The circuit is basically the same with the LED joule thief  in terms on how it works, but of course with different parts. You can use this circuit for your phototherapy session and you can direct its light to your ears, nasal airways, and other parts.

Led driver schematic

Part List:

R1, R3 - 1.2 kilo ohms 1/4W

R2 - 2 kilo ohms 1/4W

C1 - 47uF electrolytic capacitor rated 3V

C2 - 470pF ceramic capacitor

L - 470uH inductor

LED - red or any low power LED (visit LED pinout in case you forgot)

Q1, Q2 - 2N2222, 9013 or similar NPN transistor

Note: There are lots of studies about this therapy but the circuit presented above has no approved therapeutic claims.

Infrared Remote Control Tester

This is a fairly easy circuit that can be used to test TV and VCR remote controls. The infrared detector module (GP1U52X) (Radio Shack 276-137) produces a 5 volt TTL pulse train corresponding to the digital code of the particular remote control key pressed. In the lower circuit, the module output is normally low with no signal received and becomes a positive going pulse train when a signal is present. Other detector modules are available that have an inverted output as shown in the upper drawing which is the type I used, but I don't have the part number, I believe it was removed from a VCR. 

The pulse sequence represents the digital code of the particular key pressed along with possible manufacturer information. As the pulse train occurs, the 4.7uF capacitor is charged to about 3 volts and the capacitor voltage minus a diode drop appears across the 470 ohm resistor yielding a collector current from the 2N3904 or 2N3906 of about 5 milliamps. The collector current of the first stage flows into the base of the output transistor (MJE34 or 2N3053) which delivers around 250 mA into the indicator lamps. When the pulse train ends, the capacitor slowly discharges through the base of the first stage transistor allowing the Xmas tree lights to remain on for a about 1 second. The little Xmas lamps will operate over a wide voltage range, so you can use bulbs from almost any string, but bulbs from shorter strings (35 or less) will probably last longer operated at 5 volts.

The circuit can be powered from a small 9-12 volt DC, 250 mA or greater wall transformer. It may also need an additional 1000 uF filter capacitor across the DC output if the wall transformer does not have a built in capacitor. For use with a 9 volt battery, the incandescent lamps can be replaced with a regular LED and 680 ohm resistor and the output transistors can be replaced with small signal transistors (2N3904 or 2N3906). The total current drain will be about 25 mA with the LED lit, and 15 mA standby when the LED is off.