SmaTrig - 15-in-1 trigger for SLRs The SmaTrig is a compact, AVR microcontroller based multi-function flash or camera trigger. Its 15 modes of operation make it come in handy in many situations. Besides the interval modes for time-lapse photography it is equipped with sensors for light and sound for capturing short-duration events or high-speed photography. Trigger modes Manual triggerBulb exposure (switch toggles state)Flash trigger2nd flash trigger (TTL)Lightning trigger (uses mirror lock-up)Sound triggerInterval exposure 2.5 minInterval exposure 1 minInterval exposure 32 secInterval exposure 16 secInterval exposure 8 secInterval exposure 4 secInterval exposure 2 secInterval exposure 1 secInterval exposure 0.5 sec Manual Trigger - This is the simplest mode of operation. BULB exposure - Pressing the pushbutton toggles the trigger between open and closed. Flash trigger - In this mode the camera is triggered directly by the photo-diode. The operation is explained in the following. The Circuit Low power considerations Parts
Futurlec, The Electronic Components and Semiconductor Superstore SOS electronic 101 Spy Gadgets for Evil Geniuses Finding Parts - Hobbyist / Surplus Sites The data on the "Finding Parts" pages is actually all in a Wiki (a webpage that anyone, even you, can edit!) If you have suggestions or ideas for other companies or sources you can post it in the forum but it might be faster and easier to just edit the wiki page yourself! (You'll have to make an account "Not the best, but still a good deal" This is not an exhaustive list, but these are my favorite surplus locations. Check in for specials, sales, and limited-quantity items. General Surplus parts and components Dan's Small Parts and Kits A wide variety of transistors, diodes, inductors, caps, crystals, discreet RF devices, standoffs, connectors etc. Evil Mad Scientist Laboratories lots of fun kits, cool "BulbDial" clock, awesome 12" and 2.3" 7 segment displays, LEDs, ICs, Servos, Stepper motors, tools, Proto and bread board stuff. Tayda Electronics DigiKey eCrater Lots of random stuff on the rest of the website. Engineering Shock Electronics Maplin Sparkfun Electronics Mouser Electronics
Hobby Engineering Single Op-Amp Twin-T Band-Pass and Notch Filter | Simple Circuit Diagram This is a Single Op-Amp Twin-T Band-Pass and Notch Filter circuit. This circuit uses the twin-T topology which requires one or two op amps and three resistors and three capacitors. That’s mean this topology based on a passive (RC) topology. The component values are determined by following equation: Bandpass configuration: C1 = C2 = C R1 = R2 = R R3 = R/2 C3 = 2C Fo=1/(2pRC) R4 and R5 are used to control gain with R4>100*R5 Notch configuration: R1 = R2 = R C1 = C2 = C R3 = R/2 C3 = 2C Fo = 1/(2pRC) R4=R5:HIGH If the components are matched too closely, the bandpass circuit will oscillate.
HVW Technologies: Microcontrollers, Embedded Software, Development Tools and Robotics TME A new multi-function power supply unit for my Embedded Lab One important parameter in embedded system designing is power consumption. This parameter is directly related to the battery lifetime, if the system is to be powered from a battery. In order to determine the power rating of your designed system, you need to know how much current the system draws from the source at a given voltage. While working on my projects, I usually measure current by placing an external ammeter in series with the current’s return path. This is not always convenient to do, and so I thought of making a special power supply unit for my lab that would display both voltage and current information on a LCD screen while prototyping my circuit. This way I can continuously monitor how much power my test circuit is drawing at a specific operating voltage. Multifunction bench power supply This power supply unit provides fixed ±5 V as well as a variable dc voltage ranging from 1.25 V to 9 V. Theory The fixed ±5 V power supplies are derived using LM7805 and LM7905 regulator ICs.
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