Power Supply - softerhardware/Hermes-Lite2 GitHub Wiki

The Hermes-Lite 2.0 requires a 11 to 16 VDC power supply capable of supplying at least 2.0A. Although 11 to 16 VDC is supported, it is best to stay in the 12 to 13.8 VDC range. The supply input is protected against polarity inversion.

A 2.1mm center pin 5.5mm outer diameter barrel connector is expected to supply power to the Hermes-Lite 2.0; the positive terminal must be on the inside connection and the negative (ground) on the outer shell. If you don't have this connector, a inexpensive source of cable with the correct barrel connector is your local thrift store.

A low noise linear power supply should be used for best results, although many quality switching power supplies can be just as good. One way to test a power supply for noise is to measure the noise floor with no antenna using Quisk at maximum LNA gain of +48dB. A better power supply should result in a lower noise floor.