REFRACTOR PROFESSIONAL OVERDRIVE
11
MAIN PCB: DIODES
PART VALUE
D1
D9E
D2
D9E
D3
1N4001
D4
1N4001
Z1
1N4742A
Next, you’ll populate the diodes. Diodes are polarized, so make sure to identify the polarity band (which
indicates the “cathode”, or negative side) and match the band to the footprint on the PCB.
Germanium diodes will sometimes have more than one band. In these cases, the larger or wider band is
the one that indicates the cathode side.
Precautions with germanium diodes
Germanium diodes are fragile and require more care than the other components. Make sure to observe
the following precautions when working with them.
• To prevent stress on the glass body of the diode, when bending the leads, use needle-nose pliers or
tweezers to clamp the lead as close to the body as possible while you bend it down. The bend should
be about 0.05–0.08” from the body of the diode, so make sure to use pliers that are narrow enough.
• Old-stock diodes can sometimes develop corrosion on the leads, making them difficult to solder. It’s
recommended to use sandpaper or a small file to gently rough up the leads where they will make
contact with the solder. This will make adhesion much easier.
• Be quick when soldering. Germanium diodes can easily be damaged by overheating. Contact with
the soldering iron should be limited to 1-2 seconds maximum. If you don’t have a good solder joint,
wait a minute or two for it to cool before trying again.
The germanium diodes included with this kit have been individually tested and verified as working.
Unless they arrive damaged, free replacements will not be offered, so please be careful!
