Summary:
I am trying to wake up a flash unit from sleep mode using the same momentary SPST switch that is used to fire (flash) the unit.
Details:
The flash unit can be fired with a SPST momentary switch, and the voltage in this trigger loop (from the flash unit) is just under 6 volts. After 90 sec of flash unit inactivity, the flash internal electronics make the flash go to sleep, and the trigger voltage drops to zero.
Adding a small voltage (1.5 volts from an external battery) via a separate momentary SPST switch between the flash ground and a different contact (not the trigger contact) will wake the flash up, so it can be triggered by the primary mommentary SPST switch. This is actually how a camera mounted flash is woken up when it goes to sleep.
I am trying to use just a single SPST momentary to trigger the flash, then when the trigger voltage goes to zero (flash goes to sleep), this switch press will add the small external voltage not to the trigger contact, but to the secondary contact.
It would seem that a small SPDT relay could do this switching, but adding the relay into the trigger circuit interferes with the actual firing of the flash. I am looking for another (hopefully simple) set of switching components that will detect the drop in voltage of the flash even with the momentary switch in the open position, and then allow this momentary switch to close a different circuit to wake up the flash and then allow the firing from this same momentary switch.
Any suggestions or help would be most appreciated! Thanks!
I am trying to wake up a flash unit from sleep mode using the same momentary SPST switch that is used to fire (flash) the unit.
Details:
The flash unit can be fired with a SPST momentary switch, and the voltage in this trigger loop (from the flash unit) is just under 6 volts. After 90 sec of flash unit inactivity, the flash internal electronics make the flash go to sleep, and the trigger voltage drops to zero.
Adding a small voltage (1.5 volts from an external battery) via a separate momentary SPST switch between the flash ground and a different contact (not the trigger contact) will wake the flash up, so it can be triggered by the primary mommentary SPST switch. This is actually how a camera mounted flash is woken up when it goes to sleep.
I am trying to use just a single SPST momentary to trigger the flash, then when the trigger voltage goes to zero (flash goes to sleep), this switch press will add the small external voltage not to the trigger contact, but to the secondary contact.
It would seem that a small SPDT relay could do this switching, but adding the relay into the trigger circuit interferes with the actual firing of the flash. I am looking for another (hopefully simple) set of switching components that will detect the drop in voltage of the flash even with the momentary switch in the open position, and then allow this momentary switch to close a different circuit to wake up the flash and then allow the firing from this same momentary switch.
Any suggestions or help would be most appreciated! Thanks!
