I want to use this remote control as a replacement for an original Grundig remote control, in which some keys no longer work properly. So I have done the batteries from the old remote control still works well in itself in the Ersatzferndienung. The disappointment was great, because the keys or the TV reacted only when aimed exactly at the infrared receiver. The slightest deviation nothing worked. Then I set up the batteries back into the original remote control, and here it was enough, the device only about toward the Fersehgeräts and it worked until just on said, häugif used keys. I will now, willy-nilly order an original Grundig Fernbediedung.