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Proma 131020 cabinet :
Installing the tuner PCB
and ventilation
pa0nhc 20180131

After drilling ventilation holes, electrical contacts must not be seen nor be touch able.
Use a good strain relief for the mains cable, as this protects you against a short circuit between mains cable and cabinet.
Glue the four plastic feet to the outside of the bottom part.
The 8 self tapping screws are easier and safer to install, when lubricated with a little grease.

        Ventilation.
Use a print of the
top-silk to determine the locations where ventilation holes in the top part of the cabinet should be. 

Drill 3mm holes every 10mm.
        In the top cover part :
- Above the mains transformer
- Above VR1
- Above zener diodes D105 and D106
- In both sides, a row in the top most recession.

        In the bottom part :
- In both sides, a row in the top most slit (this is above the PCBs top surface).
        (The mains filter contacts may not be seen).
- A row at a distance of 5mm from, and in parallel with, the front plate.


        Installing the tuner PCB.
Check for ample free space (>= 2mm) between  :
        solder points on the PCB and the bottom
        mains filter lugs and the side of the cabinet
        mains switch lugs and mains filter
Bend or clip lugs if needed.

For easier installation of the PCB from the front side, and removal of the back plate, the wires connected to the mains filter should have ample length.

- Solder the 230V~ cable to the mains switch and the net filer NF.
- Connect the mains switch to mains filter NF.

Slide the PCB into the bottom part of the cabinet.
Slide the back panel into the bottom part.

Install onto the front plate :
    R15 with the solder lugs directed to the left
    Both insulated BNCs with their ground lugs downwards.
        They may be soldered directly onto the designated ground planes near the corners of the PCB.
    The LED

Connections to the BNCs should be as short as possible.

Shift the front plate into the bottom cabinet part.
- Solder R15 connections.
- If possible, solder the ground lugs of the BNCs directly onto the ground surface of the PCB.
        Or else connect them with short pieces of wire.
- Solder short wires to the BNC center pins
- Connect the LED.