Quote from: Batucada on 15 May, 2024 11:50My search on the net was unfortunately overshadowed by the results for a receiver with 77.5 kHz, which is close, but not really. I am therefore looking for a receiver for 5 kHz whose output signal can be forwarded to an Arduino or Raspberry Pi.You may want to search for VLF receiver schematics. There are plenty of examples, from very simple to very complicated, but the are usually schematics that you need to build, not a ready made module like the 77.5kHz receiver for the DCF77 time beacon signal.If you have an oscilloscope, try to receive the signal by simply hooking the GND aligator to the tip of the probe, like in this:
The loop of wire will behave like an antenna. That will show the exact frequency and the modulation type. Mine was emitting 110kHz pulses, on/off keying like this:
If you don't have an oscilloscope, for 5kHz you could use a sound card as well, as suggested before, then record and look at the waveform with Audacity, or with some other sound editor. If the signal is not audible, use a longer wire and make a bigger loop with more turns. If still not enough signal, then make a tuned antenna instead of just a loop of wires.Once you can see the signal, you can decide if a simple tuned loop is enough, or if it needs amplification. Any audio amplifier should do it. I would start with the above tests in the hope that the signal might be strong enough to feed the ADC of an Arduino (with only a tuned antenna and no additional amplifier).