Wireless triggering of one time use flash bulbs in flashgun, from a Yongnuo RF603 II radio trigger

It works fine the first triggering after the cable has been attached. After that it simply stops firing the flash (the trigger does register the press). I can make it work again by disconnecting and inserting the plug again.

Obviously my tests apart from a few has been done with a test bulb. But that shouldn’t matter.

The capacitor charges and puts a current over the trigger, but that is not different from electro flashes. And the maximum voltage is far from exceeded.

Any ideas why, and how to fix it?

Polarity of the capacitor, doesn’t seem to matter, since I tried reversing it.

Solved it! Never thought to look on YouTube.
Of course you need to flip the battery as well.

Edit: Remember to hold the bulb with a cloth, sleeve or paper napkin in layers and look away when inserting it, as the connection with the trigger is somewhat liable to set the bulb of. Although not with a too high frequency, according to my test bulb.
Just had two misfires.