Philco Model 16B Shouldered Tombstone Radio (1935)
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This is the fourth and final model in the series of remarkable
Philco 16 Baby Grand (16B) table radios that first appeared in
June of 1933. Introduced in January of 1935 at a price of $95, it
was one of several new "shouldered tombstone" sets that Philco
debuted half way through their 1935 model season. In my
opinion, its butterfly-shaped grille, set into a front panel of highly
figured butt walnut and tastefully offset with contrasting trim,
conveys a sense of unimposing yet elegant simplicity. But let this
unassuming facade fool you not, for it masks one of the era's
most powerful and very best performing tabletop radios.
The features offered by the 16B were advertised in 1935 as:-
Philco 16 Baby Grand (16B) table radios that first appeared in
June of 1933. Introduced in January of 1935 at a price of $95, it
was one of several new "shouldered tombstone" sets that Philco
debuted half way through their 1935 model season. In my
opinion, its butterfly-shaped grille, set into a front panel of highly
figured butt walnut and tastefully offset with contrasting trim,
conveys a sense of unimposing yet elegant simplicity. But let this
unassuming facade fool you not, for it masks one of the era's
most powerful and very best performing tabletop radios.
The features offered by the 16B were advertised in 1935 as:-
"The finest, most powerful table model ever built, in an
exquisite new cabinet of choice hand-rubbed woods"
exquisite new cabinet of choice hand-rubbed woods"
Even though this set marked the end of the line for the model 16
tabletops, its outstanding legacy would continue on into the 1936
season in the guise of the 116B.
Today, this highly collectible model is quite difficult to find and I
consider myself fortunate to have come by this one.
tabletops, its outstanding legacy would continue on into the 1936
season in the guise of the 116B.
Today, this highly collectible model is quite difficult to find and I
consider myself fortunate to have come by this one.
- Super Class-A audio system
- Shadow tuning
- Bass compensation
- Philco simplified fast and slow
motion tuning - Automatic Volume Control
- Four point Tone Control
- Four tuning bands
- Illuminated station recording dial
- Philco High-Efficiency tubes
Tune in the world with this new Philco Baby Grand!
| Technical details This version of the 16B has a tuning range of 540-22,500kc in four ranges. It's an ac-powered super-heterodyne with the 11-tube line-up:- 78 (RF amp), 77 (mixer), 76 (LO), 78 (1st IF), 78 (2nd IF), 37 (2nd det/AVC), 77 (1st AF), 42 (AF driver), 2 * 42 (push-pull AF) and 80 (rectifier). See also my 16B Art Deco tombstone, 16B cathedral, 16L and 16X pages. Schematic. Note that this table model uses the code 125 chassis whilst a code 126/127 chassis, with a 5Z3 rectifier, was employed for the updated floor models. Major Circuit Changes Relative to the Earliest Model 16Bs The second and later models in the series of 16B tombstone radios featured a number of circuit changes relative to the original, perhaps the most significant of which was the addition of a tuned RF amplifier, which improved the set's sensitivity and noise figure. Possibly as a concession to the additional waveband switching complexity with this new stage, the Philco designers reduced the number of wavebands from five to four, while keeping frequency coverage approximately the same as for the early model. To keep the tube count at eleven, the squelch (QAVC) tube was eliminated, though as it turns out Philco was not alone amongst manufacturers in doing this*. Squelch was designed to eliminate background noise while tuning between stations and it required the establishment of a somewhat arbitrary "quieting" or cut-off level, set using a potentiometer at the rear of the chassis. In practice this adjustment proved difficult to achieve with any degree of consistency, as noise conditions varied significantly from one installation to another. The squelch also had the unfortunate characteristic of suddenly muting or "chopping up" the audio from a desired station if that station experienced a momentary signal fade. Even though a toggle switch was provided on the side of the sets to turn on or off the squelch to overcome these shortcomings, the fact that a tube was now needed for the RF stage meant that squelch simply had to go! The side toggle switch was however retained for use as a bass boost on/off control. Given the addition of an RF amplifier, Philco was able to improve the automatic-volume-control (AVC). The first generation 16, with no RF amp, had AVC applied to the mixer and both IF stages, with the 2nd IF controlled only partially. The application of AVC to the final (2nd) IF stage was generally known at the time to have a detrimental effect on tone quality, contributing to a phenomena known as "modulation rise", responsible for serious audio distortion on strong local stations. The later designs therefore eliminated the application of AVC to the 2nd IF amp, which now ran with fixed bias, and applied it only to the RF and first IF amplifiers. This practice would continue to be followed by Philco in the design of their larger sets for many years. *McMurdo Silver, "1934 Laboratory-Built Super", Radio News and The Shortwave, Nov 1933 |
Restoration
I had been looking for this model for some time when I came across this particular set at the Westford, MA, Radio show in Feb of
2007. However, it was in very dilapidated condition and I initially passed it by (as did numerous others!). As the show progressed
however, I decided to buy it as a restoration project, especially once a $10 price sticker appeared upon its front! The thumbnails
below tell the story of the set as found and at various points during the restoration process.
Over a period of several months, I dis-assembled the radio, stripped off the old finish, which included an ugly, flaking coat of paint
and re-glued the panels, all of which were seriously de-laminated and buckled as a result of long-term moisture exposure. In re-
building the panels, I first completely separated the layers of ply and then re-built each panel layer by layer. At each step, while the
glue was drying the panel was securely clamped between heavy boards in order to straighten it. A sheet of replacement walnut
veneer was used on the top panel as much of the original was missing. I set aside this original as a color reference for the re-
finishing process. Finally, once a couple of small veneer patches had been made to the front panel, the cabinet was re-assembled.
To preserve its structural integrity, the original nails and screws, cleaned of rust, were re-inserted just where I had found them to
begin with. Other than the replacement sheet of veneer on the top, all pieces of the cabinet remain original.
A grain filler was applied to the front and top and the case was re-finished using toning and clear lacquers. Dark walnut toner was
used for the dark areas while the front panel was lightly toned using medium brown walnut. I used the traces of finish seen on the
original top sheet of veneer (that I had set aside) as well as my original "as found" photos of other areas as a guide to the choice
of toning lacquer used.
At this point, other than a light cleaning, I haven't restored the chassis but I plan to have it on the bench here very soon!
I had been looking for this model for some time when I came across this particular set at the Westford, MA, Radio show in Feb of
2007. However, it was in very dilapidated condition and I initially passed it by (as did numerous others!). As the show progressed
however, I decided to buy it as a restoration project, especially once a $10 price sticker appeared upon its front! The thumbnails
below tell the story of the set as found and at various points during the restoration process.
Over a period of several months, I dis-assembled the radio, stripped off the old finish, which included an ugly, flaking coat of paint
and re-glued the panels, all of which were seriously de-laminated and buckled as a result of long-term moisture exposure. In re-
building the panels, I first completely separated the layers of ply and then re-built each panel layer by layer. At each step, while the
glue was drying the panel was securely clamped between heavy boards in order to straighten it. A sheet of replacement walnut
veneer was used on the top panel as much of the original was missing. I set aside this original as a color reference for the re-
finishing process. Finally, once a couple of small veneer patches had been made to the front panel, the cabinet was re-assembled.
To preserve its structural integrity, the original nails and screws, cleaned of rust, were re-inserted just where I had found them to
begin with. Other than the replacement sheet of veneer on the top, all pieces of the cabinet remain original.
A grain filler was applied to the front and top and the case was re-finished using toning and clear lacquers. Dark walnut toner was
used for the dark areas while the front panel was lightly toned using medium brown walnut. I used the traces of finish seen on the
original top sheet of veneer (that I had set aside) as well as my original "as found" photos of other areas as a guide to the choice
of toning lacquer used.
At this point, other than a light cleaning, I haven't restored the chassis but I plan to have it on the bench here very soon!
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