Shared Projects by Cereal_Killer

Very simple transistor based oscillator circuit I made from random parts out of my crap bin. Play with the parts values to change frequency. BOTH SIDES MUST MATCH or it will not flash! You can either wire in remote mounted LED’s (such as on alternating wings) or you can use 5mm LED’s directly on the back of the board if you had a use for that, they’ll mount directly in the vias.You can also use threw hole components with some interesting soldering, pretty much any NPN- bipolar transistor will work, you can also use a wide range of values for the R2/R3 and cap sets HOWEVER you need to maintain a similar ratio as found in my example or you can easily get to a flashing rate to fast to perceive. R1 and R4 don’t effect the flash rate.

• R1 & R4 are the set resistors for the brightness of each LED (these two may be mismatched, especially if using different color LED’s)
• R2 & R3 drain the cap’s
• Q1 and Q2 are any NPN BJT’s in an SOT-23 package
• CAP POLARITY IS CRITICAL! CAP’s + goes to LED-
• CAP pads are for 3216 metric (1206) size caps such as Kemet T series. Make sure you’re using minimum 25v rated caps, 10v tantalum caps are VERY common and WILL BLOW, check the datasheet for the letter voltage code if needed!
• Supply with raw 1s to 4s LiPO, can be powered directly from flight pack or even off a 5v pin from your flight controller.

My personal values:

• R1 & R4 = 220ohms
• R2 & R3 = 10K
• total of 44uF each side (using a pair of 22uF’s caps per side)

One final note, remember that on tantalum cap’s are normally marked with the line on + (what the SMD pads are marked for) so if you’re using threw hole cap’s you’ll probably need to ignore that (most threw hole caps have the line on -)

Headlight unit for special version of 3D printed tricopter, uses CARLCO 20mm TIR optic in holder, that gives you lots of choices of beam pattern to suite your flying needs; from spot light “tight” beams of light to a wide diffused even “wall of light” and even an oval beam option optimized for fast forward flight [when orientated vertically].

• JR style servo plug
• Utilizes separate MCPCB for heat wicking from LED
• Simple jumper to select power source (JP1)
• Current selectable also via jumper (JP2), either 350 or 700mAh
• Cree XM-L2 makes 110 or 350Lm (depending on current)

Can be controlled one of three ways

• On anytime 5V is applied (JP1 closed)
• Switched by enable signal (pulled up) from controller, separate 5v source can be constantly supplied (like from BEC), this removes the load from the FC / MCU pin used for remote control (JP1 open)
• PWM’d for brightness control. This requires additional coding and a spare HW PWM pin (JP1 open)

Note tho 700mAh is VERY LOW power for an XM-L2 because there is no physical heatsink it’s highly advised to use a DIRECT THERMAL PATHWAY MCPCB such as a SinkPAD. On top of the DTP for heat a Copper MCPCB will provide a decent bit of mass to more effectively disperse heat into the air. A copper MCPCB should also be reflowed directly to the via matrix for both better heat transfer and a more secure mount for the LED / optic.

No where near ready DO NOT ORDER!

single side 10mm FET driver for SOT-23 MCU’s (PIC or ATTiny10)

single side 10mm CC driver, for PIC or AVR!