specific servo and jaw system. This is crucial since it lets
the Wee Little Talker board know the limitations of
movement so it doesn’t drive the servo/jaw combo past
the limits of your physical setup.
LED Eyes Style: This has three options: Always Off,
On During the Show, and Always On. The
most common setting is On During Show as it
causes your skull’s eyes to light up at the
beginning of the audio file and then turn off
when it’s over.
Prop Cycle Delay: This is used so that
after the audio file has finished playing, a delay
is enforced before the board will respond to
another trigger. This is useful to make sure the
device isn’t being constantly triggered by an
overzealous use of a footswitch pad or
children standing in front of the prop and
waving their hand in front of the PIR.
Additionally, if the trigger is set to “auto start,”
this value will be used as the delay between
Prop Trigger: This has three options: Auto
Start, Positive Trigger, and Negative Trigger. In
Auto Start mode, the prop will start playing
when powered up and repeat after the delay
set in “prop cycle delay.” In Positive Trigger
mode, a LOW to HIGH transition of the
trigger input will cause the prop to start. This is
commonly used for PIR sensors. In Negative Trigger mode,
a HIGH to LOW transition will start the prop. This is
commonly used for step switches or pushbutton start-up.
Embedded Amp Volume: This has five options that
set the volume of the onboard DF Player Mini MP3 board.
The values are Quiet, Low, Normal, Loud, and Over-Driven. Though many folks will probably use an external
amplifier to make sure their prop is heard if it is to be used
in a loud environment, the Over-Driven level is loud
enough to allow a small desktop display to be clearly
understood. The onboard amplifier makes it possible for
you to place a speaker inside your talking skull for a truly
Enough Talking! Now
So, now that we’ve thoroughly explored the Wee
Little Talker board, let’s get started on creating its new
home. There are multiple steps in this part of the project,
but none of them are truly difficult. Take it a step at a time
and you’ll be done before you know it. You can find a
complete list of the products used and the corresponding
links in the Resources section.
This build uses a skull with a removable skull cap
which allows access to the inside. This is where the servo
and controller will be installed. All the electronics fit inside
which means the power supply cable and/or speaker
trigger wires (if you are using them) are all that are
running out of the skull. I prefer to use the second class
skulls in order to save some money.
My attitude is that the imperfections improve the
44 September 2017
■ FIGURE 15. Can you grind between the lines?
■ FIGURE 14. Jaw securely pivoting on the zip ties.