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In the modern world, when we want to make
something happen automatically,

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we use these newfangled computer things.

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Whether that means a huge industrial automation
system controlling robots in a factory, or

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an Arduino you learned how to program to do…

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whatever the kids do with Arduinos these days...

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our modern world is based on bits of silicon
executing instructions.

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It’s a pretty great place to be

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- for now -

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but to me it’s not all that interesting.

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What is much more interesting to me is the
wild world of electromechanical wonders that is...

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pretty much all general-purpose automation
from 1975-ish and before.

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Electromechanics is my favorite kind of automation.

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Why?

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Because using nothing but switches, some motors,
some relays, maybe a solenoid or two,

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and a heckuva lot of ingenuity, you can make surprisingly complex things happen,

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all without a single bit of code.

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For example, a jukebox!

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This here is the Statesman, by Wurlitzer.

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This beautifully brown beast hails from the
year 1970.

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I mean of course it does.

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This may be the ugliest jukebox ever produced.

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It’s… even as an outspoken fan of the
color brown, this is not very attractive.

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But!

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At least with the lights on we get some purple!

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Also known as the 3400 series, this jukebox introduced the new Wurlamatic record changer mechanism.

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Which, sadly, was a radical departure from
Wurlitzer’s previous designs which put the

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mechanism on full-display.

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Here it’s hidden, but luckily I have the
key to open it up.

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Now what this mechanism does is fairly obvious
upon a short glance.

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I mean, it’s got a carousel of records,
an arm to grab hold of one of them and place it on

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this little turntable, and so obviously the
carousel will rotate to a specific record,

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stop, the arm will grab it, put it on the
turntable with the selected side facing up,

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let go of it, then the tone arm will move
into position to play it, and once it’s

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done the tone arm will return to its resting
position, the record-grabby arm will grab

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it again, put it back, and we’re done.

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So, let’s see how that works in action.

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I’ll be selecting M3 which will play the
A side of the green record.

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Pay attention to the sounds it makes.

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[two clicks as buttons are pressed]

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[a whirring mechanical sound]

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[a clunk and a loud buzzing as the carousel moves]

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[another clunk, whirring]

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[two clicks]

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[another click]

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[whirring stops]

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♫

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Alright, and now that the record is over,
watch what happens.

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[a click, followed by the whirring again]

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[various mechanical sounds as the record is put back]

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[carousel buzzes as it moves]

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You might think that the carousel will stop
once it gets back to its starting position

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[faint double-click]
but it actually continues for one more rotation.

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Then, it comes to a halt.

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[clunk, and buzzing stops]

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Now you might ask, how does it know what record
to play?

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What was the point of that sound before the
carousel started to move?

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[button being pressed; whirring]

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[buzzing of carousel]

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And more generally, what are the brains of
this operation?

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If there isn’t a microcontroller controlling
things all micro-like, how can it be controlled?

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The answer is a whole bunch of weird, purpose-built
mechanisms,

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rats nests of wires,

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and a staggering number of switches.

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That’s it.

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Electromechanics are really quite simple as
a concept, but the applications can be a little complex

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at least on the surface.

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Before we get too far into the electro-side
of things,

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let’s look at the mechanics more closely.

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The heart of the Wurlamatic mechanism is right
here.

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This controls everything the jukebox does
aside from record selection.

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And all of its functions are performed by
a simple electric motor and a gear reduction drive.

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Here, I’ve re-wired the motor to a constant
power source.

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You’ll notice that it simply repeats the
same actions over and over again.

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Grab the record.

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Put it down.

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Move the tone-arm.

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Then the same thing in reverse.

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It’s just a constant back and forth.

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But notice how much it’s actually doing.

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It may look like it’s just moving the arm
back and forth but it’s a lot more than that.

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Most of everything that’s happening is happening
because of this one very complex mechanism.

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The mechanism is powered by the main cam
motor underneath it,

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and as the mechanism rotates, so do a series of cams.

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A cam is a sort of oddly-shaped wheel that
rotates around a shaft, and thanks to its

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odd shape, it translates rotational movement
into linear movement with the help of a cam

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follower which gets pushed as the cam rubs
against it.

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In fact built into the drive gear is a vaguely-heart-shaped
groove which serves as the cam that operates

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the record arm.

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It’s a little hard to see, but there’s
a little peg riding in this groove, and it

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causes the record arm to pivot backwards,
away from the record carousel with the help

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of this little ratchet and gear thing.

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At its pivot point, these three gears serve as the means by which each side of the record is selected.

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Pins on the two side gears will stop either
one of them from turning when they hit these catches.

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This then causes the arm to rotate sideways
as it continues to pivot backwards.

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Depending on which pin is stopped, it will
rotate in either one direction or the other,

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and this solenoid moves the catch points back
and forth, therefore its position determines

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which side is played.

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In its resting state, it will rotate to play
side B by default, and when the solenoid

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is energized, it catches the other pin to
play side A.

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Obviously the most noticeable thing this mechanism
does is move the record take-out arm,

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which is its official name, by the way.

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But thanks to a series of other cams adjacent
to the main drive gear, and the various linkages

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they attach to, it does much more, too.

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The single cam in front of the main drive
gear releases the record from the arm by way

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of this linkage, which also pulls the turntable
slightly to the left so the record can spin

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freely of the arm.

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Two of the cams behind the drive gear move
the tone arm to play the record, with one

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responsible for lifting it up and the other
for moving it left and right, and there’s

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even a cam just for activating this little
button which switches the amplifier from its

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auxiliary input to the phonograph input when
a record is being played.

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Take a look at this exploded diagram.

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This is everything going on inside the Wurlamatic
mechanism.

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There are 7 cams in total, though that’s
not perfectly true as you’ll see later.

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But anyway, these seven cams are the programming
of the physical actions that take place.

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Their shape and position dictate at what points
in the mechanism’s 360 degree rotation

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each action will occur.

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This may not look like a program, but it very
much is.

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Note that the cams could be made to cause one
action to happen multiple times per cycle,

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if required.

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However, this clever mechanical program doesn't
make for a useful jukebox all by itself.

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If it just runs all the time, well then that
wouldn’t do anything but make a bizarre

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record flinging dance.

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We need a way to control when the program
starts.

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Of course we also need to pause the program
in the middle when the arm has reached the

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turntable so the record can actually play.

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And then we'll need to restart the program to
put the record back.

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Of course, finally there needs to be a way to shut down
that program altogether once that task is complete.

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So we need some sort of additional control.

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Of course, before I re-wired the motor, it
didn’t start moving until the correct record was in place,

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and it was automatically stopping
in both the record playback and its resting positions.

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How did it do that?

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Well, what makes it automatic is the plethora
of micro-switches you see all over the place

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that function as interlocks, interrupts, start-stop
points, and triggers for other ancillary actions.

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OK, so here’s something that’s super common in electromechanics

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and is gonna come up a few times here.

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Self-latching circuits with interrupts.

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Using a relay, we can design a circuit that
will latch itself in a closed state

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until another action occurs.

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What is a relay?

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Well, a relay is an electrically operated
switch.

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A small electromagnet within the relay opens
or closes any number of switch contacts.

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One of the most common things we do with relays
is control high power devices with low voltage,

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low current control circuitry.

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But we can also be almost endlessly clever
with them.

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So, let’s say we want to turn on this light
bulb with a momentary pushbutton switch.

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We could wire the bulb right to the pushbutton,
but of course that means it’s only lit

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so long as the button is held in.

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And it also means the button has to handle
all of that current.

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What I want is for the button to turn the
light bulb on, and for it to stay on

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after the button is released.

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Here’s a simple circuit which will accomplish
that by latching itself closed.

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12 volts DC power is used here on the control
side of the relay,

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but the load side of the relay can be whatever we want it to be.

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This relay is now the switch which turns the
light bulb on, and it will do so whenever

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the relay receives 12 volts DC power.

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So, we’ve got a 12 volt supply and a ground for the relay, with the bulb wired on a completely separate

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120V circuit through one of the normally
open contacts of the relay.

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If I wire the 12 volt supply through the pushbuton,
now the relay will energize whenever the button

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is depressed, which closes the switch contacts
inside the relay, and turns on the light.

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This also has the benefit of making the button’s
electrical connections safe to touch, since

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they’re now just handling 12 volts.

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But, the light still goes out as soon as you
release the button because the relay loses

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its 12v power source.

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However, if I branch off the 12 volt supply to another of the normally open switch contacts of the relay,

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then feed the other side of
that back into the control side input,

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what now happens is that as soon as I push the
button, the 12 volt control side becomes self-powered.

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The button is now completely out of the picture,
as it becomes bypassed by the relay itself.

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The relay is now stuck in the closed position,
or latched… forever.

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At least, until the power supply is cut.

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Taking a closer look, we now have a second
power source coming from before the switch.

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This has 12 volts on it at all times.

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Again, it’s going to the second set of switch
contacts of the relay, and its output is being

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fed back to the control side.

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If there’s no power from the button, well nothing
happens.

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But as soon as the button supplies power,
that second wire snaps into action,

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bypassing the button, and keeping the relay energized.

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But, if I cut that second wire feeding the
relay and put a second button across it,

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this one with normally closed contacts, that means I
can interrupt the 12v supply that’s keeping

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the relay energized in order to deactivate it.

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Now, I press the “on” button, which energizes
the relay.

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This of course turns on the light bulb, but
also creates that new 12-volt supply for the relay

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to stay on indefinitely, but that new supply
now travels through this second button.

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When I press it, it momentarily breaks the
12-volt supply to the relay, which de-energizes it,

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and the light goes out.

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However, as soon as the green button supplies
12 volts again, even for just a tiny fraction of a second,

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the relay provides a bypass
for itself once more, and the light stays on.

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Pretty clever, huh?

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There are all sorts of applications for a
circuit like this.

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For example, a garage door opener!

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Push one button, the motor starts, and it
doesn’t stop until a limit switch at the

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end of the door’s travel opens the circuit.

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Of course, you’ll also want to design in
some safety interlocks, and other stuff, but hey.

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It would work.

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It might also kill someone.

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But it would work!

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So then, how does this apply to the jukebox?

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Well, the Wurlamatic has a microswitch that
serves as an interrupt to a latched relay.

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It’s the red button in our previous example.

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It rides along the edge of the main gear.

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That’s why I said there are more than seven
cams, because this is also its own kind of cam.

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Once the program is started, it will continue
to run on its own because a relay, specifically

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the Main Cam Relay, is latched in.

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But it’s latched through this, the transfer
switch.

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Now, you’ll notice that the switch doesn’t
actually get actuated...

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♫ abruptly slow jazzy blues kinda music ♫

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Ooh, twangy!

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Now, you’ll notice that the switch doesn’t
actually get actuated until the main cam has

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moved a little bit.

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Why is that?

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Well, because at first, either the Side 1
or Side 2 relay serves as the power source

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for the main cam relay.

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Electromechanics can get a little complicated.

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The same device can receive power from multiple
places, but so long as you sequence things

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correctly, you can manage it.

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When the carousel has reached the correct
selection, either the side one or side two

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relay will be activated.

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That starts the main cam program, just like
pushing the green button.

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However, the signal from the first relay will
disappear shortly after the record arm has

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moved from its resting position.

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We’ll get into the specifics of why that
happens when we get to the delightfully named

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Selection Accumulator.

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To put it more simply, a signal caused this
motor to start turning, just like the green

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00:13:57,670 --> 00:13:59,610
button turned on the relay.

224
00:13:59,610 --> 00:14:04,050
But to keep it turning we need to generate
a new signal because we’re gonna lose the

225
00:14:04,050 --> 00:14:07,160
first one, just like releasing the green button.

226
00:14:07,160 --> 00:14:08,740
And that’s what this switch does.

227
00:14:08,740 --> 00:14:14,260
The transfer switch keeps the main cam relay
energized, and thus the main cam motor running,

228
00:14:14,260 --> 00:14:18,720
all the way through its rotation, until the
record is put back at which point it is released.

229
00:14:19,860 --> 00:14:20,860
But wait.

230
00:14:20,980 --> 00:14:22,340
That’s…

231
00:14:22,340 --> 00:14:23,340
a problem.

232
00:14:23,380 --> 00:14:27,400
Doesn’t it need to stop midway through to
actually play the record?

233
00:14:27,400 --> 00:14:28,860
Indeed, it does!

234
00:14:28,860 --> 00:14:34,060
So, there is another switch at play here,
appropriately called the Play Switch.

235
00:14:34,060 --> 00:14:37,153
This is actually a sort-of second red button
in this scenario,

236
00:14:37,153 --> 00:14:39,620
but it’s not going to totally kill the circuit.

237
00:14:39,620 --> 00:14:41,980
Instead, it will just sort of pause it.

238
00:14:41,980 --> 00:14:44,440
Ironic for a switch named Play.

239
00:14:44,440 --> 00:14:48,000
Whenever the transfer switch is engaged, the
main cam relay is, too.

240
00:14:48,010 --> 00:14:50,089
So it wants to move the mechanism.

241
00:14:50,089 --> 00:14:54,490
But, once the play switch is activated by
this cam, it interrupts the flow of power

242
00:14:54,490 --> 00:14:58,330
from the transfer switch and de-energizes
the main cam relay.

243
00:14:58,330 --> 00:15:01,520
This then causes the entire Wurlamatic mechanism
to stop.

244
00:15:01,520 --> 00:15:03,550
And now the record can play.

245
00:15:03,550 --> 00:15:07,450
Incidentally, this switch does double-duty
and the same switch which mutes the

246
00:15:07,450 --> 00:15:12,120
amplifier’s auxiliary input to give priority
to whatever record is playing.

247
00:15:12,120 --> 00:15:16,550
The key difference here is that the transfer
switch is still trying to sending power to

248
00:15:16,550 --> 00:15:21,240
the main cam relay, but it’s being interrupted
by the play switch.

249
00:15:21,240 --> 00:15:23,650
So what happens when the record is over?

250
00:15:23,650 --> 00:15:26,880
If this circuit was designed like our red
and green button thingy,

251
00:15:26,880 --> 00:15:29,640
well if the red button's being held in,

252
00:15:29,640 --> 00:15:33,480
we would need another green button to provide power and start it back up.

253
00:15:33,860 --> 00:15:34,820
Do we have one?

254
00:15:35,280 --> 00:15:36,100
Well, yes!

255
00:15:36,100 --> 00:15:39,100
That’s the trip switch, located right here.

256
00:15:39,100 --> 00:15:43,600
It’s activated by the tone arm once it’s
near to the run-out groove of the record.

257
00:15:43,600 --> 00:15:48,940
This then bypasses the play switch, allowing
current to go around it, and thus re-energize

258
00:15:48,940 --> 00:15:52,420
the Main Cam relay to restart the program.

259
00:15:52,420 --> 00:15:56,150
Now here’s a bit of nuance which is very neat and I want to highlight it.

260
00:15:56,150 --> 00:15:59,450
The trip switch works as a bypass for the
play switch, right?

261
00:15:59,450 --> 00:16:04,560
Which, again, the play switch stops everything
so the *record* can play.

262
00:16:04,560 --> 00:16:08,330
The play switch isn’t letting power through
to the main cam relay, but the trip switch

263
00:16:08,330 --> 00:16:10,029
provides a workaround.

264
00:16:10,029 --> 00:16:15,380
But that means that the programming of all
these cams needs to be done such that the

265
00:16:15,380 --> 00:16:20,320
play switch gets released before the tone
arm is pulled back to its resting position.

266
00:16:20,320 --> 00:16:25,220
Otherwise, the play switch would just cause
things to come to a halt once more as soon

267
00:16:25,220 --> 00:16:28,260
as the tone arm moved away from the trip switch.

268
00:16:28,260 --> 00:16:31,540
You can see that things were programmed just perfectly

269
00:16:31,540 --> 00:16:36,050
so that the play switch gets released, then the tone arm moves

270
00:16:36,050 --> 00:16:38,730
This is why electromechanics are so fascinating
to me.

271
00:16:38,730 --> 00:16:43,680
It’s a delicate ballet of logical circuit
design and physical interactions.

272
00:16:43,680 --> 00:16:45,779
You need to make this action to stop?

273
00:16:45,779 --> 00:16:48,270
Well, just make it hit a switch that kills
it.

274
00:16:48,270 --> 00:16:49,620
Oh, you need it to start up again?

275
00:16:49,620 --> 00:16:52,520
Well, just add another switch that un-does
the first one.

276
00:16:52,520 --> 00:16:56,220
And make sure you get the timing right or
it won’t work at all!

277
00:16:56,220 --> 00:17:03,060
Basically, there are a ton of if/then statements
in here, but manifested as wires and switches.

278
00:17:03,060 --> 00:17:06,120
It’s a form of logic, but very rudimentary.

279
00:17:06,120 --> 00:17:10,549
When you combine that with crazy mechanisms
like the Wurlamatic, you find yourself with

280
00:17:10,549 --> 00:17:15,560
a machine that can do surprisingly complex
things all through whatsists and doodads.

281
00:17:15,560 --> 00:17:17,880
None of that there computery business.

282
00:17:17,880 --> 00:17:21,720
And you'll also find some important safety interlocks,
too.

283
00:17:21,720 --> 00:17:26,420
For example, notice how when the record grabby
thing grabs the record from the carousel,

284
00:17:26,420 --> 00:17:30,990
it ends up between the two records surrounding the one it’s grabbing.

285
00:17:30,990 --> 00:17:35,210
Well, what if the record carousel were to
move with it in that position?

286
00:17:35,210 --> 00:17:38,539
A bunch of records would be broken by the
little hook.

287
00:17:38,539 --> 00:17:43,980
To keep that from happening, the motor which
turns the carousel is wired through this microswitch,

288
00:17:43,980 --> 00:17:49,029
which is only depressed when the Wurlamatic
mechanism has opened the jaw of the…

289
00:17:49,029 --> 00:17:50,769
right, the take out arm.

290
00:17:50,769 --> 00:17:52,360
That’s what it’s called.

291
00:17:52,360 --> 00:17:56,440
This prevents what we in the business call
"a bad day".

292
00:17:56,440 --> 00:18:00,230
And of course you’ll find some other switches
here that do other groovy things, like the

293
00:18:00,230 --> 00:18:02,609
Side 2 Release Switch.

294
00:18:02,609 --> 00:18:05,450
This is what actually releases the side 2
relay.

295
00:18:05,450 --> 00:18:10,009
There’s another one, of course, for the
side 1 relay, and these function just like

296
00:18:10,009 --> 00:18:12,289
the red buttons in our little demo rig.

297
00:18:12,289 --> 00:18:18,519
Both the side 1 and 2 relays are self-latching
to get the main cam relay, and thus the entire

298
00:18:18,519 --> 00:18:22,899
mechanism going, and these two switches are
responsible for releasing them.

299
00:18:22,899 --> 00:18:27,359
You’ll notice that it’s the same pins
which are used to turn the take-out arm that

300
00:18:27,360 --> 00:18:29,860
actually actuate these two switches.

301
00:18:29,860 --> 00:18:34,940
But of course, we haven’t answered perhaps
the most important question about this machine.

302
00:18:34,940 --> 00:18:37,220
What gets this all started?

303
00:18:37,230 --> 00:18:39,620
How does it know to start turning the carousel,

304
00:18:39,620 --> 00:18:43,020
and how does the carousel know what record to stop at?

305
00:18:43,020 --> 00:18:45,520
Or what side to play?

306
00:18:45,520 --> 00:18:48,320
Well, I’m gonna save that for the next video.

307
00:18:48,320 --> 00:18:51,620
Yeah I know, I know, I’m sorry, but this
is already, what,

308
00:18:51,620 --> 00:18:52,560
[NINETEEN]

309
00:18:52,560 --> 00:18:53,060
minutes long?

310
00:18:53,060 --> 00:18:54,060
Or thereabouts?

311
00:18:54,320 --> 00:18:57,480
But before I go, let’s look at one more
thing.

312
00:18:57,480 --> 00:19:01,249
I bet you didn’t think you could just remove
the record carousel, but you can.

313
00:19:01,249 --> 00:19:03,840
It’s actually just sitting in here.

314
00:19:03,840 --> 00:19:06,740
Just select a record to be played, then shut
if off.

315
00:19:06,740 --> 00:19:07,679
[sound of music stopping[

316
00:19:07,679 --> 00:19:11,330
Now, the carousel can simply be lifted up
and out.

317
00:19:11,330 --> 00:19:12,779
Look at what’s underneath.

318
00:19:12,780 --> 00:19:16,680
It’s connected to this black arm which can
be spun around.

319
00:19:16,680 --> 00:19:20,140
This is clearly going to some sort of mechanism
below it.

320
00:19:20,140 --> 00:19:25,720
That mechanism is the Read-out Arm and it,
along with the Selection Accumulator,

321
00:19:25,720 --> 00:19:29,340
are perhaps the most amazing parts of this entire
machine.

322
00:19:29,340 --> 00:19:34,120
The Selection Accumulator is what made the sound you
heard before everything got started.

323
00:19:34,120 --> 00:19:34,920
This one.

324
00:19:34,920 --> 00:19:36,780
[rapid clicking, followed by whirring]

325
00:19:36,780 --> 00:19:37,320
[click]

326
00:19:37,320 --> 00:19:39,500
[carousel spinny-buzz begins]

327
00:19:39,500 --> 00:19:45,040
Notice when I select a record that the buttons
stay depressed until that sound stops.

328
00:19:45,040 --> 00:19:46,940
Then they pop back out.

329
00:19:46,940 --> 00:19:49,480
That's actually the reason there's a reset button in the middle,

330
00:19:49,480 --> 00:19:52,520
so that way if you press the wrong button you can pop it out.

331
00:19:52,520 --> 00:19:56,880
Now, listen closely as I select a series
of records.

332
00:19:56,880 --> 00:19:58,120
A1

333
00:19:58,120 --> 00:20:00,560
[whirring]

334
00:20:00,560 --> 00:20:01,060
[clunk as it stops]

335
00:20:01,180 --> 00:20:01,920
C1

336
00:20:02,920 --> 00:20:03,440
[whirring]

337
00:20:03,440 --> 00:20:03,940
[click]

338
00:20:03,940 --> 00:20:05,300
[whirring]

339
00:20:05,300 --> 00:20:06,000
[clunk as it stops]

340
00:20:06,060 --> 00:20:07,100
E1

341
00:20:07,740 --> 00:20:08,640
[whirring]

342
00:20:08,640 --> 00:20:09,140
[click]

343
00:20:09,140 --> 00:20:10,120
[whirring]

344
00:20:10,120 --> 00:20:11,120
[clunk as it stops]

345
00:20:11,120 --> 00:20:12,500
G1

346
00:20:12,500 --> 00:20:14,040
[whirring]

347
00:20:14,040 --> 00:20:14,540
[click]

348
00:20:14,540 --> 00:20:15,040
[whirring]

349
00:20:15,040 --> 00:20:16,120
[clunk as it stops]

350
00:20:16,120 --> 00:20:17,040
and J1.

351
00:20:17,900 --> 00:20:19,800
[whirring]

352
00:20:19,800 --> 00:20:20,300
[click]

353
00:20:20,300 --> 00:20:21,360
[clunk as it stops]

354
00:20:21,640 --> 00:20:24,680
Did you notice something changing with each selection?

355
00:20:24,680 --> 00:20:27,080
[whirr...

356
00:20:27,320 --> 00:20:27,980
[whirr...

357
00:20:27,980 --> 00:20:28,480
click]

358
00:20:30,080 --> 00:20:31,120
[whirr...

359
00:20:31,120 --> 00:20:31,620
click]

360
00:20:32,860 --> 00:20:34,300
[whirr...

361
00:20:34,300 --> 00:20:35,000
click]

362
00:20:35,680 --> 00:20:37,620
[whirr...

363
00:20:37,620 --> 00:20:38,180
click]

364
00:20:39,140 --> 00:20:40,360
What's going on?

365
00:20:40,420 --> 00:20:44,800
Well, stay tuned because in the next video
we’ll find out.

366
00:20:44,800 --> 00:20:45,660
Thanks for watching.

367
00:20:45,660 --> 00:20:50,420
I really hope you enjoyed this video and that
my explanations were easy enough to follow.

368
00:20:50,420 --> 00:20:55,320
Electromechanics are really quite simple,
but they can be a little confusing.

369
00:20:55,320 --> 00:20:59,080
When you use switches and relays to make sequences
and interlocks,

370
00:20:59,080 --> 00:21:01,080
it can seem to get out of hand.

371
00:21:01,080 --> 00:21:04,639
In fact, these here are the schematics for
this machine.

372
00:21:04,639 --> 00:21:07,229
They’re super easy to read!

373
00:21:07,229 --> 00:21:11,320
You might have thought this was a pretty simple
device with what you’ve seen up ‘till now,

374
00:21:11,320 --> 00:21:12,230
but trust me.

375
00:21:12,230 --> 00:21:17,400
When we explain where these buttons go, it’s
gonna get a lot more complicated.

376
00:21:18,240 --> 00:21:20,440
I think I’ll play some music now.

377
00:21:20,440 --> 00:21:21,620
How about…

378
00:21:21,620 --> 00:21:22,620
T1?

379
00:21:22,620 --> 00:21:23,980
[ buttons being pressed ]

380
00:21:23,980 --> 00:21:25,720
[ selection accumulator whirring ]

381
00:21:25,720 --> 00:21:29,000
[ buzzing as carousel moves ]

382
00:21:30,160 --> 00:21:32,080
this is gonna take a while...

383
00:21:33,420 --> 00:21:36,220
shoulda picked something in the C's or D's...

384
00:21:38,740 --> 00:21:43,400
[ clunk, followed by various mechanical sounds ]

385
00:21:43,400 --> 00:21:44,580
[a low hum]

386
00:21:44,580 --> 00:21:48,320
♫ scratchy low-fidelity smooth jazz ♫

387
00:21:58,200 --> 00:22:00,680
♫ audibly improved smooth jazz ♫

388
00:22:02,260 --> 00:22:05,220
I liked that delivery so much and then it
fell apart!

389
00:22:05,220 --> 00:22:08,660
And a staggering number of switches, rel … ooh.

390
00:22:08,660 --> 00:22:10,780
Ha, that’s the, that’s the end of the
sentence!

391
00:22:10,780 --> 00:22:11,280
[laughs]

392
00:22:11,280 --> 00:22:11,780
oops.

393
00:22:11,780 --> 00:22:13,100
Did I say “of course” weirdly?

394
00:22:13,100 --> 00:22:16,710
It’s a little late now, ‘cause I’m already
moving it back, but I think I did.

395
00:22:16,710 --> 00:22:21,600
However, this clever mechanical program wouldn’t
make for a useful jukebox…

396
00:22:23,180 --> 00:22:26,120
it’s later than you think it is, I’m kinda tired.

397
00:22:26,129 --> 00:22:28,160
When I press it, it morment...

398
00:22:28,160 --> 00:22:29,560
[weird stress
sounds]

399
00:22:30,440 --> 00:22:31,960
Those are fun words!

400
00:22:31,960 --> 00:22:33,880
They aren’t words, they’re just sounds

401
00:22:33,880 --> 00:22:35,879
So what happens when the record is over?

402
00:22:36,380 --> 00:22:36,879
Oh.

403
00:22:37,680 --> 00:22:40,279
It’s not phrased as a question that I know
the answer to.

404
00:22:40,279 --> 00:22:42,029
I should have added a paragraph here.

405
00:22:42,029 --> 00:22:42,820
I need to…

406
00:22:42,820 --> 00:22:45,040
I need to say something that’s not in the
script.

407
00:22:45,040 --> 00:22:46,320
That’ll go well.

408
00:22:49,280 --> 00:22:53,560
Stay tuned for next time when we 
ACCUMULATE SOME SELECTIONS

409
00:22:54,420 --> 00:22:57,520
I'm very excited for the next video.

410
00:22:57,520 --> 00:23:00,040
I think you're gonna like it.

411
00:23:02,000 --> 00:23:02,960
doo doo doo doo