City Theatrical 1504 User manual

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1504 Follow Spot Yoke
Source Four LED Series 3
Rev 1.0
© 2022 City Theatrical, Inc.
Made in USA

City Theatrical Follow Spot Yoke
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Getting Started with the CTI Follow Spot Yoke for Source Four LED Series 3
Congratulations on the purchase of your City Theatrical Follow Spot Yoke for Source Four
LED Series 3. The City Theatrical Follow Spot Yoke is a professional quality device that can
provide smooth pan and tilt operation to your Source Four LED Series 3. A heavy steel yoke
gives mass and prevents vibration, and ball bearings on the pan and tilt create extremely
smooth movement, even on very long throws.
The 1504 City Theatrical Follow Spot Yoke can be configured for use with the Source Four™
Series 3 LED fixture. All lenses from XDLT 5º to 50º can be used. A track allows the lighting
fixture and any accessories to be perfectly balanced for ease of operation.
SET FOR RIGHT HAND OPERATION
Mounting Brackets
Tee Slot Extrusion, one set
of two pieces, 10” long.
Shoulder Screw,
3/8” x ½”, 5/16”-18 thread,
3/16” Allen key.
Tilt Hand wheel
Yoke
Pan Bearing
Pan Lock Knob
Light fixture facing this direction

City Theatrical Follow Spot Yoke
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Mounting your Follow Spot Yoke Source Four LED Series 3
The City Theatrical Follow Spot for Source Four LED Series 3 can be mounted in a variety of
ways. The bottom of the pan bearing has female 1 ½” NPT pipe threads, and any length of 1
½” pipe can be threaded into it. Using a 36” piece of 1 ½” pipe threaded into a 50 lb. boom
base is a typical method.
The Follow Spot Yoke can be mounted in a variety of positions, such as:
•On a stand of 1 ½” pipe with a boom base
•Underhung from a pipe
•Overhung on a hand rail
These diagrams illustrate three possible hanging methods:
Pipe and base mount
Overhung on
handrail
Underhung on pipe

City Theatrical Follow Spot Yoke
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Preparing Your Lighting Fixture
If you are planning to use a 14º-50º or a 10º Source Four, you will need to remove the
shutters from the lighting fixture. This is not necessary, but may be desirable for a 5º Source
Four to prevent the shutter blades from accidentally being moved during operation. Remove
the shutters by removing the four machine screws which hold the two halves of the Source
Four barrel together and exposing the shutter, pressure plate, and shutter spring parts.
Remove the shutter blades, but reinstall the pressure plates and springs. Only reinstall the
two machine screws on the neck of the barrel. Then go on the next step:
Two Angle Brackets allow your Source Four to be installed in the Follow Spot Yoke Source
Four LED. Replace the two ETC Torx machine screws with the enclosed M4x12 pan head
Phillips machine screws. Then use the original hex bolt and washer to fasten the angle
bracket.
Next, install the two Tee Slot Extrusions using the enclosed #8-32 x 3/8” flat head Phillips
machine screws (three screws per extrusion) as shown in the illustration below.
Note: If you experience difficultly installing M4x12 screws, it may be due to incompletely
threaded holes on the Source Four barrel. Threads can be formed completely with the
following steps:
1. Remove the bottom half of the barrel, locate the threaded holes in the barrel.
2. Using the original Torx thread-forming screw to finish the thread on the bottom half of
the barrel.
Angle Bracket
Tee Slot
Extrusion
#8-32 x 3/8 Flat Head
Machine Screws
M4x12 screws
Original Hex Bolt
and Washer

City Theatrical Follow Spot Yoke
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Installing the Source Four into the Follow Spot Yoke
Note the two Tee Blocks that slide into the Tee Slot Extrusion. Using a 3/16” Allen key, slightly
loosen the two 3/8” x ½” socket head shoulder screws to free the Tee Blocks. Carefully insert
the Tee Slot Extrusions onto the Tee Blocks. Tighten the tilt handwheel. Temporarily tighten
the shoulder screws.
Install four 4-40 x 3/16” pan head machine screws, one in each end of each Tee Slot
Extrusion. These screws serve as safety devices to prevent the Tee Blocks from accidentally
slipping out of the Tee Slot Extrusion track.
Install the Lens Tube into the Source Four
Install the Lens Tube into the Source Four and install the two #10-32 screws (one plastic
thumbscrew and one Philips machine screw) that hold the Lens Tube to the lighting fixture.
Plug in the lighting fixture into a switch or dimmer and dress the cable to ensure that it does
not restrict the yoke’s movement or its balance. Turn on the lighting fixture and adjust the
sharpness of the beam to the degree that you think is appropriate.
Shoulder Screw
Tee Slot
Extrusion
Tee Block
Tilt Handwheel
#4-40 x 3/16” machine screws

City Theatrical Follow Spot Yoke
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Balance the Lighting Fixture in the Yoke
The lighting fixture can be adjusted forward or backward in the Tee Slot Extrusion to establish
a perfect balance point. To test the balance, carefully loosen the tilt locking knob and feel if
the fixture is front heavy or back heavy. To adjust the balance, loosen the two shoulder
screws and evenly push the fixture forward or backward in the Tee Slot Extrusion until it
balances exactly. Lock the shoulder screws again. Test and repeat if necessary.
Adjust balance as needed

City Theatrical Follow Spot Yoke
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Using Other City Theatrical Accessories with Your Follow Spot Yoke
City Theatrical has created a range of accessories to make your Follow Spot more versatile
and easier to operate.
Part
Number
Name
Use
2180
Drop-In Iris
Change size of beam
1520
Follow Spot Yoke Handle
Provides handgrips at front of Follow Spot.
1519
Follow Spot Source Four LED
Series 3 Handle
Clamps onto the rear of Source Four LED Series 3 to provide
a handgrip.
2180
1520
1522