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is it circuit is correct? plzz help me plzzzzz

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New Member
plzz help me. is it circuit woking?


How it Works:--- is it corrcet circuit? plzz tell me

Resistors R1 and C1 have a time constant much greater than the time between the two flashes. R3 limits the current into the base of Q1, and ensure that Q1 is turned on long enough to discharge C3 through R4. The time constant of C3 and R4 is long enough to allow the flash to fire. Diode D1 and capacitor C1 form a simple power supply, allowing the unit to be powered from leakage current from the flash. Resistor R5 supplies a bias current to the slave adapter so that it can see the flashes. The pre flash turns on Q1, and Q1 stays on until C2 is drained through R3. The hot shoe adapter employs an SRC in its output, the current supply by R5 must be less than the sustain current of the SCR, but the current supplied by both R2, R3 and R5 should be greater than the sustain voltage. I believe that I may have R3 a bit large. With Q1 on, Q2 cannot turn on. After the pre flash, C2 recharges almost fully before the main flash, however, C1 does not recharge significantly. When the main flash is picked up by the slave unit,.Q1 does not turn on, and therefore Q2 is allowed to turn on and the external flash fires. The resistor and capacitor value are not highly critical, and with some tinkering, this circuit should be adaptable to a large number of flashes and hot shoe adapters. Another good modification would be to replace Q2 with an SCR, and possibly increase C1 so that the unit can suppress red-eye reduction flashes too.

SLAVE UNIT - A light-sensitive triggering device that is built in or attached to an electronic flash unit, causing the flash to fire simultaneously with another flash unit. Also called a "photo slave."



New Member
ingeneous you've just solved all the power problems of the planet, an entire circuit that can run without power, surely this can be developed for large scale use ?


This looks like som crackpot free energy scheme - drop it, it won't work!


New Member
It's just a slave flash driver so you can have two flashes fire at the same time. Simple circuit.

Build it and see if it works.
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