My Circuit

Stage Center Reverb Bill of Materials Resistor ((1/4 watt rating) 2 - 4.7k 1 - 10k 1 - 22k 1 - 33k 1 - 47k 1 - 470k 1 - 1M 1 - 2.2M Pots 2 - 50k log can be linear or log (audio) taper. Capacitors (minimum 16 volt rating) 1 - 220pF 1 - 0.01uF 2 - 0.02uF 3 - 0.22uF 2 - 39uF Op Amp 1 - TL074 Other Reverb Springs - Input Impedance of 310 Ohms (Accutronics 4DB2C1D) Reverb Springs Bag (optional) 2 - cables with RCA jacks on both ends. These are used to connect the reverb springs to the circuit. 1 - 3PDT or DPDT heavy duty foot switch 2 - 1N4001 diodes 1 - 14 pin op amp socket (optional) 1 - Stereo Quarter inch Jack (input) 1 - Mono quarter inch jacks (output) 2 - RCA female jacks 2 - 9v battery snaps & holder and/or DC jack(s) Copper-clad board, etchant, 24 gauge stranded wire Enclosure affiliate program

The bi-directional sequencer uses a 4 bit binary up/down counter (CD4516) and two "1 of 8 line decoders" (74HC138 or 74HCT138) to generate the popular "Night Rider" display. A Schmitt Trigger oscillator provides the clock signal for the counter and the rate can be adjusted with the 500K pot. Two additional Schmitt Trigger inverters are used as a SET/RESET latch to control the counting direction (up or down). Be sure to use the 74HC14 and not the 74HCT14, the 74HCT14 may not work due to the low TTL input trigger level. When the highest count is reached (1111) the low output at pin 7 sets the latch so that the UP/DOWN input to the counter goes low and causes the counter to begin decrementing.  When the lowest count is reached (0000) the latch is reset (high) so that the counter will begin incrementing on the next rising clock edge. The three lowest counter bits (Q0, Q1, Q2) are connected to both decoders in parallel and the highest bit Q3 is used to select the appropr...