Muscle to micro servo circuit

Does the servo move if you manually adjust the voltage at pin 5?

Be aware that some breadboards have a break half-way along the power rails so you may have to bridge them or power each half separately.

Hi,

You don't seem to have wired up pins 4 and 11 of the TL074 chip.

Hello,

I teach breadboarding skills and my immediate reaction to your photos is to say that the easiest remedy to your wiring issues is to tidy up the way you do your breadboarding. I would ask you to do this before I would even attempt to help troubleshoot the circuit.

It is very hard to comprehend complex wiring when it is "spaghetti wiring" (a term my fellow instructors and I use to describe the way you've done your breadboarding) with long leads on your components crossing over each other.

A search for examples of "tidy breadboarding" yielded the photo below from Instructables.com

Note how the resistor leads are clipped short so that they can be placed very neatly on the board. Similarly, the wires are just long enough to do their job. Capacitors, LEDs, and other components should also have their leads clipped to reasonable lengths. You will need to bend the leads at 90 angles using needle nose pliers to keep things this tidy.

This does take extra time and skill to do when initially constructing your circuits, but it saves huge amounts of time when troubleshooting or modifying your circuits.

Some beginners are reluctant to clip the leads on their components, thinking they we need the extra length for future labs/projects. However, components are easily reused unless the leads are clipped off extremely short. Jumper wires can be used to interconnect them

The Instructables example is overly neat. You don't need to go to that extreme.

Ben Eater, one of my YouTube heroes, is an electronics expert and has an excellent video on this subject (entitled Breadboarding Tips)

With regards,

Rick

Thanks Shabaz, i dont see pins 4 or 11 on the schematic though. The pinout says 4 is Vcc and 11 is Vee, i vaguely remember the prof saying thats for voltage in and out, by my old man brain may be mis-remembering. And even that wouldnt make much sense as 6v and 9v are already conected at various points.  Priciate the reply.

Thanks for the suggestions Rick, ill add tidiness to the list of many things i need to learn.

Good call Dave. Fortunately, the prof brought that up early in the lessons, my board is connected all the way through. Thanks for the reply.

Pins 4 and 11 are in fact on the schematic.  They are the power pins to the Op-amps, shown connected to 9V and -9V.

Thanks Doug. Right now i only have a 1.5v x 4 pack, and 2 9v connectors, so im not sure how i would manully adjust the voltage. A voltage regulator is on the shopping list though.