Trying to get a RPM7100 IR detector going (Jaycar cat no ZD-1952). I have the IR source emitting a 38 KHz square wave, as specified, but the device appears to only respond to sudden changes in the received light signal, ie. if I hold it steadily in front of the continuously emitting diode, the output stays high. The data sheet is fairly vague (increasingly common problem?), but it does specify maximum, typical and minimum values for a
600uS 'subcarrier' (my term), suggesting that the device is designed to activate if it receives a 38 KHz carrier that is pulsing on and off every 600 uS.Checked some other sources, they all bring up the same datasheet.
Can anyone confirm what the behaviour of this device is? TIA