Philco Model 19 "Baby Grand" (19B) Cathedral Radio (1933)
The Philco 19B Baby Grand was introduced in early 1933 and was the
latest in a series of models that used the Clyde Shuler designed
cabinet introduced the previous summer. The 19B's cabinet is quite
compact and in my opinion, its proportions are more pleasing to the
eye than the other, larger models that share the cabinet style. The
initial 1933 purchase price was $37.50, though by year's end, in time
for Christmas, it was being advertised for $50 ($52.50 in the West).
The model 19B used a new Philco 6-tube superheterodyne chassis.
Early production covered the standard broadcast band only and
featured a two-point tone control. However, in the summer, ready for
the 1934 season, the radio was upgraded to cover the police and
amateur band and to provide a four-point tone control ("brilliant, bright,
mellow, deep"). My model is this later version, distinguishable by its four
knobs (the early model had three).
The model 19B also featured Philco's shadow tuning, first introduced
in the summer of 1932 for the model 91. This development was
described in Philco advertising as follows:-
19B... Powerful new Baby Grand with shadow tuning & other big set features.
"Philco Shadow Tuning gives you absolutely correct tuning, instantly. A
shadow band that is projected on a screen immediately above the station
dial contracts in width as you approach a station, reaching its narrowest
dimension when you are right on the hairline of perfect tuning"
" A Child can tune with Philco Shadow Tuning... marks the greatest
advance in ease of operation ever invented. It is revolutionary, yet so
simple a child can tune perfectly"
The model 19B's new 6-tube superheterodyne chassis tuned the standard broadcast band from 540-1500kc and, for the late version, the
police/amateur band from 1500-3200kc. The chassis was, I believe, Philco's first to use the newly introduced type 75 tube, a duo-diode/triode
that combined the functions of "detector rectifier" and "detector amplifier". The use of this multi-type tube facilitated the development of a
6-tube chassis having not only an RF stage, but also Automatic Volume Control (AVC). Contrast this with the 5-tube model 51B/52B offered
just about a year earlier, which had no RF stage nor any AVC. The one significant development still missing from the 19B 's circuit was the
pentagrid converter, which would further advance performance of the lower tube-count sets by increasing the efficiency and reliability of the
converter as well as by allowing AVC to be applied to that stage in addition to just the RF and IF amplifiers, as was the case for the 19.
However, the pentagrid converter's adoption would have to wait for some of Philco's 1934 models, introduced later in 1933.
The 19's tube line up is 44 (tuned RF amp), 36 (LO/mixer autodyne circuit), 44 (IF amp), 75 (2nd detector/AVC/1st AF), 42 (AF output) and
80 rectifier). The schematic for the two-band model may be found here, courtesy of philcoradio.com.
I bought this radio at the NEARC show in NH in 2003. It had been slopped with a coat of tinted shellac at some point in its
history (click the thumbnail to the right to see it). In late 2006 I used denatured alcohol to strip off the shellac, revealing an
almost pristine original lacquer finish below. I was just amazed that anybody would have felt inclined to cover up that
wonderful old finish with such a poorly applied and ugly coat of shellac! Anyhow, following some touching-up of the lower
trim pieces, a new decal and grillecloth, this has turned out to be one little gem of a cathedral radio.
During the same time period, I restored the radio electrically. In addition to a full recap and replacement of out-of-tolerance resistors, I had to
contend with an open-circuit shadowmeter. However, I followed the procedures outlined on Chuck Schwark's excellent philcorepairbench web
site to effect a successful repair. After a careful alignment, the radio now plays and operates beautifully!