====== H-field pre-amplifier PCB 16.x ======
original source(([[https://docs.google.com/document/d/1KzPZJW0ErInFtfTCmhNhSZTOpg6N2bgZDyIxkh_DRVs/pub?1532944531#h.iubpod4vxyrx|Documentation System BLUE]], chapter 2.2.2))

The H-field pre-amplifier board PCB 16.x has the following THT components whose placement is obvious.

^ image ^ count ^ part ^ note ^
| {{:en:hardware:blue:akl_059_03.jpg?100|}} | 1 | Header 3-pin, Pitch 3.5mm ||
| {{:en:hardware:blue:akl_059_06.jpg?100|}} | 1 | Header 6-pin, Pitch 3.5mm | (or alternatively 2 x Header 3-pin, Pitch 3.5mm) |
| {{:en:hardware:blue:rj45.jpg?100|}} | 1 | RJ45 Modular Connector ||

{{:en:hardware:blue:preamp_pcb_16_2015_06_22.jpg?400|}}

{{:en:hardware:blue:preamp_pcb_16_con.jpg?400|}}\\
The antennas are connected to the pre-amplifier as shown above.
| Signals from left to right: |||||||||
| A-1 | A-2 | GND | B-1 | B-2 | GND | C-1 | C-2 | GND |
| This corresponds in the Status page of the web interface of System BLUE to |||||||||
| Amplifier 1 - H0, Channel A ||| Amplifier 1 - H0, Channel B ||| Amplifier 1 - H0, Channel C |||
| This corresponds in the Settings page of the web interface of System BLUE to |||||||||
| Amp 1, Channel A ||| Amp 1, Channel B ||| Amp 1, Channel C |||
| This corresponds in the Signals page of the web interface of System BLUE to |||||||||
| Channel 1A, red signal ||| Channel 1B, green signal ||| Channel 1C, yellow signal |||

{{:en:hardware:blue:patch.jpg?800|}}\\
The H-field pre-amplifier is connected with a shielded twisted pair cable (FTP, STP, S/STP, or S/FTP) to the main board. This cable should not be placed next to the network cable. Please keep a distance of at least 10 cm. The cable may have a length of up to 30 meters.

{{:en:hardware:blue:h_jp.jpg?400|}}\\
If you use loop antennas, than you should close (solder) the jumper for the corresponding channels at the back side of the board.

If the pre-amplifier is powered, the red LED should light.