Most amateur photographers have a desire to connect to their soveremennym electronic flash cameras with high voltage on the Sync (up to 350 V). It can be as old Soviet outbreak and modern budgetary tools.
In such cases, guaranteed not to damage the Sync on the camera, you must connect to it via a flash converter, step down. The scheme of one variant of this adapter is shown in Fig.
This is almost the same scheme, which I quoted in the article about the Slave. I deliberately decided to repeat it here, as in this case it uses a different function. Fans of universality can combine the two functions (Slave + lowering voltage adapter) in one and the same device.
It feeds on the scheme from time battery pills 1,5 V.
Resistor R3 can, in principle, do not bet. But in this case, the inrush current to Sync camera at the time of operation can reach several tens of mA. Since most camera manufacturers do not publish the maximum allowable parameters Sync (you guess why?;)), It seemed reasonable to take measures to reduce not only stress, but also current on sinhokontakte camera. Alex Smolentsev (aka Al) proposed for this purpose in the scheme to add a resistor R3. The greater the resistance, the smaller the peak value of current when operated. However, excessively high resistor R3 may lead to the fact that even if a little run down the battery circuit will cease to operate. The required nominal R3 should be selected on the basis of this compromise. According to Alexei, he was able to reduce the trigger current of 1 mA. I note also that the magnitude of this current will depend on the particular instance of a thyristor.
Sync voltage 1,5 V and a trigger current of several mA can undoubtedly be considered safe for today’s digital cameras. Nevertheless, the author assumes no liability for any damage caused by industrial self-refining devices and / or unofficial connection.