Dual OP Kit

Product status: Planned

This is an add-on for the Otto 8 Passive. It is a DIY-KIT.

With this KIT you can create one of the following:

  • Buffered Multiple 1 to 7
  • Dual Buffered Multiple 1 to 3
  • Dual Sample & Hold
  • Sample & Hold + Buffered Multiple
  • Decisions

    First you need to decide what you want to build. The links above contain more details and building instructions for each project.

    You also need to decide if you want protection resistors on the op amp outputs. The TL074 have short circuit protection built-in, BUT it will be very hot when this happens. It is protected against shorts to ground or to the rails. You should not leave it in a shorted state because it will probably break after some time. Shorting to ground or rails is a wrong connection from the beginning, so you should avoid this at all times. In the building instructions you will see “1k or wire”. This is the places where you choose if you want a protection resistor of 1k or the wire for no extra protection.

    General tips

    • In some places you will need wires. First try to use the cut legs from already soldered components. Then use legs from unused components in the kit, but don’t cut them so that your component can’t be soldered later…
    • It’s usually best to start with the lowest components and finish with the biggest ones.
    • Don’t rush things. Finalize each soldering and make sure you don’t create any shorts or bad connections.
    • Always test what you have built before you connect it to other stuff.
    • See here how to create the power cable.
    • If you have not used the 1×2 female header, you can put it on the otto pins 31 and 32 (no soldering), and use it as a support for the pcb.

    PCB Overview

    KIT Contents

    • 8 Resistor 1k
    • 3 Resistor 10k
    • 2 Resistor 22k
    • 2 Resistor 47k
    • 2 Resistor 100k
    • 2 Resistor 1M
    • 6 Ceramic capacitor 100nF
    • 2 Electrolytic capacitor 47uF 16V
    • 2 Polystyrene capacitor 0.1uF
    • 2 Diode 1N5819
    • 2 Diode 1N4148
    • 2 FET Transistor 2N3819 or J113
    • 2 Quad Operational amplifier TL074
    • 1 Female header 1×15 position
    • 1 Female header 1×2 position
    • 1 Power connector 2×5 pin
    • 1 IDC female connector 2×5 pin
    • 1 IDC female connector 2×8 pin
    • 1 Ribbon cable 10 position, 25cm
    • 1 Pinstrip 8 pin
    • 1 wire, 9cm
    • 1 PCB
    • 1 Sticker sheet
    • Plastic zip bag


    290 SEK

    Technical specifications


    Width: 0 HP
    Depth: 28 mm

    Current consumption

    Additional files, images and videos