Offboard components
Note that the BOM above doesn’t include offboard components. These are a matter of taste, but
the basics are listed below.
• Enclosure, PCB fits Hammond 1590BB or Eddystone 29830PSLA
• Stereo 1/4”/6.35mm Input jack
• Mono 1/4”/6.35mm Output jack
• Stomp switch, DPDT or 3PDT if you want an LED indicator
• Power Input socket, 2.1mm
• LED + LED appropriate resistor
• 4 x Knobs
• Another switch for the ‘Tap’ option, if required (See “Adding more switches and options” on
Page 10).
Because of the current drain of this pedal, we don’t recommend using batteries instead of a power
adaptor. Ok, *maybe*, if you’ve got 9V rechargeables.
Component choices and substitutions
Very few of the components in the circuit are especially critical and a unit built with non-ideal
components will likely still work fine. However, in the interests of lowest noise, we recommend
you use 1% metal film resistors and good quality polypropylene or polyester film capacitors. The
board allows either 0.2”/5mm or 0.3”/7.5mm lead spacing for the film capacitors.
Transistor choice is not critical. Any medium gain, low noise NPN device will work. The board
expects a transistor with the EBC pinout, like the 2N3904. If you only have transistors with the
alternative CBE pinout like the BC547, you can fit the transistor back-to-front.
Similarly, op-amp choice is not critical. Choose any 8-pin dual audio op-amp with the standard
pinout. TL072, LF353, or MC1458 will all work. Many more audiophile options are also possible!
The PCB is laid out with
holes for various types of
trimmer resistor. Any of the
following layouts work fine.
Multi-turn trimmers are
recommended for fine
adjustment.
The power protection diode suggested is 1N4002. Pretty much any diode from this series is ok.
1N4001 will work, 1N4003 or 1N4004 are fine too, although total overkill.
The 1N4148 signal diodes can be replaced with other small signal silicon diodes. 1N914 is a direct
replacement and can be considered identical. Their role is to limit the signal to a level the BBD can
handle (and to provide a soft clipping if driven too hard), so the forward voltage is the most
significant parameter.
Flangelicious Construction Guide
www.electricdruid.net
Page 9
