HeinrichsWeikamp GbR

Cause:
The Digital Adapter gains its power from the attached strobe. Since no Ready-Line exists for Sea&Sea strobes with 4-pin interfaces, only the trigger line can transfer the power when the strobe is turned on.
While the Digital Adapter needs only 750µW to work (a 4MHz MCU is powered by it!), this load is still too much for the trigger line right after the strobe has been turned on. The strobe's inverter is still running and the battery voltage is below normal. Although Digital Adapter is running, the voltage on the trigger line drops below a level at which the strobe can be fired reliably.
If the strobe is turned off now, the Digital Adapter switches into a power saving mode. The RAM is buffered by an internal capacitor for some seconds. When re-activating the strobe now, the Digital Adapter doesn't load the trigger line and the voltage rises up to its normal level. The Digital Adapter will work perfectly well until the strobe is turned off for at least 15 seconds.

Solution:
Other than adding an additional resistor to the Trigger line (Pull-Up Resistor), there is no solution. Users have to re-activate the strobe for proper use. Fortunately, only few 4-pin Sea&Sea strobes are affected by this problem.

Problem: The Digital Adapter for Sea&Sea (4-pin interface only) works only once the strobe has been turned off and then on again:
It is a known problem that with some strobes, the Digital Adapter works only if you turn the strobe off for an instant, then switch it on again. Cause: The Digital Adapter gains its power from the attached strobe. Since no Ready-Line exists for Sea&Sea strobes with 4-pin interfaces, only the trigger line can transfer the power when the strobe is turned on. While the Digital Adapter needs only 750µW to work (a 4MHz MCU is powered by it!), this load is still too much for the trigger line right after the strobe has been turned on. The strobe's inverter is still running and the battery voltage is below normal. Although Digital Adapter is running, the voltage on the trigger line drops below a level at which the strobe can be fired reliably. If the strobe is turned off now, the Digital Adapter switches into a power saving mode. The RAM is buffered by an internal capacitor for some seconds. When re-activating the strobe now, the Digital Adapter doesn't load the trigger line and the voltage rises up to its normal level. The Digital Adapter will work perfectly well until the strobe is turned off for at least 15 seconds. Solution: Other than adding an additional resistor to the Trigger line (Pull-Up Resistor), there is no solution. Users have to re-activate the strobe for proper use. Fortunately, only few 4-pin Sea&Sea strobes are affected by this problem.
	Solder a resistor of approximately 500Ohm (e.g. 470Ohm) inbetween the white cable (Trigger) and the battery-plus (the red cable leads to the battery container on the backside of the pcb). All /S strobes will work fine now. Please head the warnings under "Modification!" Of course, the resistor should be isolated with a heat shrink or electrical tape.
This problem could be solved by a further reduction of the power usage. All Digital Adapters sold after 5/2005 are no longer affected by it!