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Assembling the auto loop tuner back panel.
pa0nhc 20150201. Adapted for new proPCB : 20181210

On the ALU back panel, the diameters of holes "MOT" (6 pole mini-din) and "Net" (strain relief) possibly must be adapted to the components you actually are using.  Drill these holes only when you are sure.

The length of the BNCs (15.9 mm) determine the free space between the back panel and the PCB. There should be ample room between them for the current transformer L1. See parts list for ordering details.

The ALU back panel serves as the "GND" connection between both BNC's. 
At the inside surface of the ALU back panel, full antenna current flows between both BNC's. 
At the mid between both BNCs, an M3x25 screw serves as the only and neutral mass connection for both back panel PCB mass surfaces.

            Assembling :
Print the back drilling template PDF with size 100%, and use it as a drill template. 
-  Adjust the picture centered to the ALU back plate, fix it with tape,
-  Mark the holes (with a center punch),
-  Drill them.

-  Wind the 10 turns secondary winding of L1.
   REM : the L1 secondary winding direction determents the phase of the output voltage, and the correct labeling of the  Ant. and TX BNCs.
   If later on, ANT and TX seem to be exchanged, then change he labeling of the BNCs, or rewind the secondary of L1 in the opposite direction.

-  On the "back panel outside side" of the PCB, install ::
   -   R202
   -   L1 and link.

-  On the "Back panel INside" of the PCB, install : 
   -   R201
   -   C201
   -   C202
   -   The shunt (0.7mm x 40mm). Solder it directly onto the solder points of the L1-link.
          See the dashed lines on the back side of the PCB.
   -   The relay.
           If the relay has a metal body, connect the metal body to mass.
   -   The four connecting wires to the rest of the circuits.

REM : Wires "I" and "Io" should be kept separated, and NOT be twisted to keep stray capacitance on "I" minimal.

-  Install the BNC's in the ALU back plane. 
   IMPORTANT for low contact resistance between panel inside, and BNC :  Place the BNC locking teeth washer under the nut.
  Tighten the nuts firmly.

-  Install the mini-DIN connector and solder (long) thin connecting wires to the pins.
   Before connecting the wires to other places, wind the bundle thin wires several times through the hole of a small Fair-Rite MIX #31 ring core.  
   All PCBs have printed wire connection IDs. They are the same as on the schematic diagram.

            Connections are:
Two motor wires from pins 3 and 4 to phase detector PCB {M1} and  {M2}
One band switch wire from pin5 to the band switch on the front panel.
One +12V anti condensation heather wire from pin6 to +12V at the power supply elco.
Two "grounding" wires from pins 1 and 2 to -12V at the power supply elco.

-  Install the M3 grounding screw with a locking teeth washer between the nut and the back plane
   Put a second nut on the screw, with on top of it a locking teeth washer.

-  Shift the PCB fully over the BNC center contacts and the M3 screw. 
   Fist put a locking teeth washer, and then a nut on the screw.
   Adjust the nuts loosely.

-  Solder the BNCs pins to the PCB, keeping the PCB in parallel with the back plane.

-  After that re-adjust, and tighten the M3 nuts firmly.

REM : when screwing the front plate or back plate onto the cabinet, put a little grease on the screw thread.
It will help easy screwing, and prevents damage to hole and screw.