I bought the radio trigger of about half a year, because he had a good price / performance ratio. The problem with the switch was aware and I had even thought about it, a retrofit. However, have my batteries after six months still 1.5V, which means that you were not nearly emptied. That's why I got the idea discarded.
On the other hand one should think about it, that all other remote controls in the home have no off switch. I have always chosen when not using the last rider because have shown the least segments ...
