I have a homebrew remote antenna switch. It uses relays and it has a nRF24L01-based wireless link to the band selector (Arduino, taps into CAT and switches antennas accordingly).
I would like to power this device without running a separate power cable. I thought of using a bias tee with about 100 to 470nF capacitors, KV rated, several in parallel, and big inductors for DC injection and extraction. Some sources online recommended using a ferrite rod to make the coil, which should provide an inductance into the millihenries.
The questions are:
- Is this a good idea?
- Will this introduce significant losses into the system?
- Will this introduce significant noise into the system?
- Is there anything else I should be concerned about?
I've seen at least one supplier of this sort of "bias tee" circutry for HF, but at a price exceeding $250 (which I'm not willing to spend), so I believe it "should work".