I also have an older model Koch intercom (don't know the exact type at the moment K50??). But it worked fine right away. The instructions were clear and I think you can find good explanations on youtube. All in all I find the Nuki super developed! Greetings Rolf
Hello, together with a Koch TC50. But not right away: I first wanted to operate the opener with a power supply unit: Failure. As it turned out later, it was because of the port that is only "blown on" the circuit board and breaks away at the slightest touch. Even a warranty replacement was no better. What Nuki is doing is subterranean. With battery operation it does not run very reliably: The connection is often not established. That's why I never leave the house without a key. Seen in this light, it's a nonsensical thing....but maybe it will get better one day.