My Rayotron nightlight was inspired by a half-million volt, electrostatic generator designed to produce high energy X-rays for research in atomic physics. The original project used a 12 volt DC supply to power a small electronic air ionizer that illuminated a miniature cold cathode lamp (CCL).The components were installed in a custom built, cardboard console fabricated from discarded 3-ring binders. A manually adjustable spark gap between the discharge sphere and a telescoping ground return permitted the flicker rate to range from a pulsing light to a steady glow.
This Rayotron reno incorporates recycled and re-purposed materials to:
- replace the shabby chic appearance of original console with a more artistic look;
- upgrade the CCL assembly;
- replace the temporary mounting of ground electrode with a permanent one;
- replace the non-functional dial on instrument panel with a functional power control circuit.
The Rayotron uses a high voltage source. Although ionizer current is minimal, an unexpected shock can cause accidents while you are working on the project. Use caution and common sense.
Step 1: Parts & Tools
The project required these items: hobby saw, insulated hook-up wire, letters (rub-on and stick-on types), finishing nails (2), painter's tape, plastic lid from a jar, sanding block w/paper (medium and fine grades), silicone reducer washer (1.5" x 1.5"), soldering pencil w/solder, spray paints (various colors), variable power resistor (salvage from an old motor control unit, or purchase unit from Ohmite), white glue and wood dowels (to plug unused machine screw holes in console base).
Step 2: Remove Components, Resurface & Repair Console
I disconnected and removed all components from the instrument panel along with the commercial power supply, ionizer and hardware. I sanded the cardboard surfaces with course then fine paper to remove original spray paint. Holes in the base (where the original, hacked power source was installed) were plugged with 3/16 inch wood dowels cut to size and held in place with white glue. I sanded the base until all plugs were level.
The entire console was prepped for repainting by rubbing a thin coat of glue on each panel; letting them dry and then sanding until surfaces felt smooth to the touch.
Step 3: Paint Console
I applied two coats of high gloss, black paint to base, side, back and front panels. Instrument and console lid are painted separately in following step.
Step 4: Paint Remaining Panels
I sprayed the lid with several coats of metallic silver paint and painted the instrument panel with metallic gold so that imperfections in the cardboard would create the appearance of a hammered metal surface.
Step 5: Mask & Paint Instrument Panel
I decided on a two-tone color scheme for the instrument panel. I used painter's tape to make a 1.2 cm border around the panel, then applied two coats of silver paint. Panel components were reinstalled and the panel was attached to the console. I installed the variable power resistor, dial plate and knob to make a functional dimmer.
- Construction Tip: Attach both hinges to instrument panel, then attach panel to console for easy access to front panel machine screws!
Step 6: Apply Letters
Black-on-gold stick-on letters were used on the front panel to spell, RAYOTRON. I lined up the letters with a strip of painter's tape. Rub-ons were used on the handle to spell, NITE LAMP -- I was missing the letters to spell, NIGHT LIGHT. (:>(
- Construction Tip: Use clear spray paint to seal edges of the letters and prevent them from peeling off.
Step 7: Replace Internal Components
Hard wire fuse, switches, lights, power supply, resistor, ionizer and meter as shown in circuit diagram. BTW, factory installed indicator light on ionizer, was desoldered and used as L2 on instrument panel.
Step 8: Modify Support Column
I disassembled the original support tube, then replaced the hand-cut plastic ring at the base with a commercial, beveled reducer washer and discarded the white plastic cap from the original project. Although this step isn't essential, IMHO, it improved the project's appearance. Next, I gave the CCL retaining cones two fresh coats of Neon Red paint.
Step 9: Make Column Pedestal
I re-purposed this mirrored, plastic top from an empty skin cream jar as a pedestal for the support tube. I drilled a center hole in the top to accommodate a #6-32 round head, machine screw. The screw was inserted through bottom retaining cone and pedestal to secure this assembly to the console lid with a ring terminal (connected to insulated hot lead of ionizer) and wing nut. BTW, I inserted a nylon sleeve to insulate the lid from the screw carrying the high voltage.
Step 10: Mount Support Column
There's not much to do here; just place the plastic column over the retaining cone and drop in the CCL so the end slides into the rubber grommit. Temporarily cap the top of the column with the remaining retaining cone. CCL should align with long axis of column.
Bottom end of CCL must contact machine screw that secures pedestal assembly to console lid to ensure a good electrical connection when you energize the ionizer.
Step 11: Attach Discharge Sphere
I used a #6-32 round head, machine screw to attach the upper retaining cone to the discharge sphere. The screw was inserted into the retaining cone, through the sphere and then exited via a hole at the opposite end. A lock washer and acorn finishing nut held everything together.
When you cap the support column with this assembly, top end of CCL must contact machine screw to ensure a good electrical connection.
Step 12: Upgrade Gnd Electrode Mount
The ground electrode of my original Rayotron was held in place with a pinch clip. I separated the telescoping antenna from the clip before removing the two wire handles, then re-inserted the antenna into the base. I slid a 4 cm finishing nail into each handle slot of the clip and then (carefully!) hammered each nail to into the lid.
- Construction Tip: For added strength, glue a small block of scrap wood under the lid, then hammer nails into block.
Step 13: Final Adjustments
Plug in power supply, flip power and ionizer toggles, then crank up the power! The CCL should flicker. Set spark gap to approximately 1 mm by moving the antenna toward the sphere with an (insulated!) screwdriver until CCL produces a continuous glow. Your renovated, Rayotron tribute nightlight is now ready to use.