Assembling the auto tuner back panel.
Parts and hole positions seen from the back panel (top copper),
Adapt the diameters of holes "MOT" (6 pole mini-din) and "Net" (strain relief) to the components you actually are
The ALU back panel serves as "GND" connection between both BNC's. The full antenna current flows here on the inside.
The M3x25 screw serves as mass connection for both PCB sides.
The MASK is dimensioned for printing centered on A5 landscape.
On this double sided PCB the tracks run on the top-copper side, here seen from the back panel.
Because your home made PCB has no metalized holes, you must solder all connections on the inside (top copper, track side) of the PCB. See below.
- Print the drilling template PDF of the back PCB with size 100% on paper.
- Tape it centered on the back plate, punch the centers of the holes, and drill them.
- Wind L1. Sec. = 10t. REM: the winding direction determents the phase of the output voltage, and the correct Ant. and TX connection positions. If ANT and TX seem to be exchanged, rewind the secondary of L1 in the opposite direction.
- Place the resistors, capacitors and L1 on the track side of the PCB, and solder them on BOTH sides. Solder the four wires too. REM: R201 can be made from 7 pieces 33k 0.25W metal film resistors in parallel.
- On the back plane (full ground surface) solder the shunt (0.7mm x 40mm), directly onto the solder points of the link. See back pcb XRAY.
- Place the relay, and solder it on the track side. If it has a metal can, solder this to mass.
- Place the BNC's in the ALU back plane. Use locking washers between the nuts and the back panel for low resistance contact. Tighten the nuts firmly.
- Place the mini-DIN connector.
- Place the M3 screw with locking washer between the nut and the back plane. Put a second nut and washer on the screw.
- Shift the PCB over the BNC center contacts and the M3 screw. Put a third nut and teeth-washer on the screw and adjust them loosely. Between the BNC center pins and the track side of the PCB there should be ample room to solder.
- Solder the BNCs on the trackside of the PCB,. After that adjust and tighten the M3 nuts firmly.
RED = back = solder link here. Place relay here.
GREEN = front = solder side. Place all other components here.
Seen from ALU back panel.