In a Nutshell
Here's World's Second Glowing Glass Rod Radio (see techies)

Introduction:

Note added Feb. 24, 2016: Turner Classic Movies (TCM) on Nov. 26 last year showed the 1942 movie "Woman of the Year". The beginning shows this radio, through which Sam Craig (Spencer Tracy) heard for the first time Tess Harding (Katharine Hepburn), his future wife's voice. Note that the knobs are wrong, the radio has the wrong push-button pressed, and changes its look between the two pictures (pict.s 41,42).
This is the second time I made the "Glowing Glass Rod Radio" (first one at ref.1). The 1939 World's Fair, "Building The World of Tomorrow" opened in April in New York (ref.2). Wedged between the great depression and the beginning of World War II, the Fair's president Grover Whalen outlined its purpose as "to place en route the world's resources in a gigantic crusade against man's chief foes: inertia, lassitude, and chance." Celebrities like President F. D. Roosevelt (opening address on TV), Albert Einstein (switched the Fair's lighting system on), Norman Bel Geddes (GM's Futurama), Gilbert Rohde (Community Interest Exhibit), Raymond Loewy (Transportation Exhibit) actively contributed to its tremendous success. GE's lightening generator, ATT's speech synthesizer, RCA's TV ("picture radio") debut, Westinghouse's walking/talking robot were only some of the Fair's lasting firsts.
Zenith's model 317 "Glass Rod" radios were marketed as "The World's Fair Special" for the 1939 model year. Its prominent and unique feature is the use of 12 glass rods, interspersed with 11 gold-painted wooden rods, as speaker grille. It is unavoidable to be reminded at the capitals Capitol (pict.42). The radio came with 3 different chassis (first digit = number of tubes), 4B317 (battery), 5R317 (transformer) and 6D317 (All-American Five with ballast tube). For sale here is again the last version. The transformer powered version is at ref.3. All versions feature Zenith's "Transcontinental Tip-Touch Tuning" innovation, "the most perfect tuning since Zenith first put Automatic Tuning on a radio in 1928". The original purchase price of this radio was $29.95.

Additional information:
 ref.1:    http://www.greenhillsgf.com/IndexOwn_Zenith_6D317.htm
 ref.2:    http://www.websyte.com/alan/nywf.htm
 ref.3:    http://www.tuberadioland.com/zenith5-R-317_main.html
 ref.4:    https://www.facebook.com/Pare-126056450790092/
 ref.5:    https://youtu.be/bfHmiIcvnFY

About my Radio:
The radio's cabinet is refinished using water based Varathane Diamond finish and observing a very conservative attitude when deciding between authenticity and the new trend for high-gloss refinishing. The back plane has been remodeled after the original from 1/8" 3-layer plywood (pict.s 17, 29, 30). The original asbestos heat shield has been replaced by a black painted sheet metal piece (pict.34), that easily absorbs heat from mainly the 30W heater string including the ballast tube and redistributes it over the whole top surface. Unlike the 2 filter caps not a single one of the reliable Zenith wax capacitors had to be replaced (pict.26). The radio has the original metal-cased ballast tube L-55-C (picts.25,35). The corrosion-free chassis is cleaned and in-depth serviced. All moving parts have been treated with contact spray. The original speaker is perfect (picts.21,24). The push-button automatic (Automatic Tip-Touch Tuning) has been cleaned, sprayed and serviced and works perfectly. The radio plays loud and clear on AM/BC, where it has good sensitivity and selectivity over the whole band spread. The radio has been uninvasively and reversibly modified to a. let the glass rods glow, enabled with a separate switch, and b. to accept mp3 players, cellphones etc. through a closed circuit 3.5mm phone jack (see techies). A youtube video has been uploaded recently (ref.5) and can be viewed inline by clicking on thumbnail 43. Please e-mail me (Kris) for any questions or comments, ich spreche Deutsch, je parle Français.

For the techies only:
Inspired by my son's development of a Foldable LED Luminaire (see ref.4 above) and convinced of the jaw-dropping effect I created for the second time the "Glowing Glass Rod" radio (pict.s 5-14). Twelve white SMD LEDs (pict.39) are placed in the little gap on top of each of the 12 glass rods (pict.19), connected in series, preceded by a current limiting resistor and powered by a DC voltage generated by a bridge rectifier from an AC voltage, supplied by the radio's tube heater string (pict.s 31-33,36,37). The LED's can be switched on and off with a miniscule extra switch at the back (pict.29). The whole modification did not alter the radio in any way except two little screw holes on the inside bottom right of the cabinet to hold the components for the LED power supply (pict.33). The modification can only be noticed by the presence of the little switch and can easily be undone. The effect is as expected - jaw-dropping (pict.s 5-14): a uniform glow over the entire lengths of the rods. In contrast to the findings for the first glowing glass rod radio (ref.1), the light is less blue and brighter at the ends of the rods. This indicates that the glass used has less impurities that would scatter light out of the rods by Rayleigh scattering and shifting it to blue. Picts. 10 and 11 seem to indicate that the LEDs are on the bottom of the rods, whereas they are on top. The light is partly channeled by total reflection on the internal glass surface from top to bottom, where it is randomly diffused back by the unpolished end. The escaping light thus is here dominated by geometric optics, not Rayleigh scattering. As for the first radio all surface imperfections act as enhanced scattering centers and appear white.
The many questions and comments I got, and the prompt sale of my first radio confirm my feeling, that the modification made was and is not a sacrilege, but enhancing the appeal of this lovely radio. In the same sense I consider the other modification - playback of mp3- and cellphones etc. as a nice bonus. In particular since they both are uninvasive and reversible.

Here are the specifications:

Please have a look at prices and more radios, phonographs and gramophones  here