Vectronics VEC-1680K - Manual (Page 11)

VEC-1680K Owner’s Manual Vacuum Tube Preamp
11
holes (see below). Also, using side cutters, remove the key tab from the side of
each pot prior to installation.
Rear pins use rear holes. Front pins use front holes.
Nip off tab.
Nip off tab.
! ! On the solder side of the PC board, mount a 500K pot at R9 and solder.
! ! Similarly, mount a 500K pot at R10 and solder.
Flip the PC board back to its component side to complete parts installation. The
next six items to install are diodes. Like electrolytic capacitors, diodes are
polarized devices that must be installed correctly. Always look for the banded
end when installing.
! ! Find the 1N4148 diode (small glass body with band at one end).
Observing polarity, install at D6 and solder.
Locate five (5) 1N4007 power diodes (black body, white band at one end).
Observing polarity, install these as follows:
! ! Install a 1N4007 at D1 and solder.
! ! Install a 1N4007 at D2 and solder.
! ! Install a 1N4007 at D3 and solder.
! ! Install a 1N4007 at D4 and solder.
! ! Install a 1N4007 at D5 and solder.
Locate the DPDT miniature relay and note the pin configuration on its base. The
pins are spaced so the relay fits only one way on the PC board. Be sure all pins
enter their mounting holes and the relay sits flush with the PC board surface
before soldering.