Philco Model 80B "Junior" Cathedral Radio (1932/33)
The Philco model 80 Baby Grand (80B) was released
in September of 1932 as part of the company's 1932/
1933 line-up. As with several of their entry-level mod-
els that had preceded it, it was nicknamed the
"Junior". The set was priced very aggressively, at
$18.75 including tubes and applicable sales taxes.
This pricing was accomplished in part by the use of a
new two-toned cabinet that was a simplification of the
Clyde Shuler design, still in use at the time for the
71B and 91B models.
Moreover, although the chassis was an ac-powered
superheterodyne, it too was very much designed
down to a cost. Philco had eliminated the IF stage,
leaving it with just four tubes and, like the low-cost
models that preceded it, it had no AVC or tone
control. The engineers made up for the lack of an IF
stage, to some extent, by adding regeneration to the
second detector. Regeneration had been exploited
extensively in the early days of radio and involved
coupling the output of a tube back to its input in such
a manner that the signal would again be amplified,
fed back to the input, and so on, around and around.
The process was controlled to stop just short of
oscillation, at which point exceptionally high amplifi-
cation was achieved.
in September of 1932 as part of the company's 1932/
1933 line-up. As with several of their entry-level mod-
els that had preceded it, it was nicknamed the
"Junior". The set was priced very aggressively, at
$18.75 including tubes and applicable sales taxes.
This pricing was accomplished in part by the use of a
new two-toned cabinet that was a simplification of the
Clyde Shuler design, still in use at the time for the
71B and 91B models.
Moreover, although the chassis was an ac-powered
superheterodyne, it too was very much designed
down to a cost. Philco had eliminated the IF stage,
leaving it with just four tubes and, like the low-cost
models that preceded it, it had no AVC or tone
control. The engineers made up for the lack of an IF
stage, to some extent, by adding regeneration to the
second detector. Regeneration had been exploited
extensively in the early days of radio and involved
coupling the output of a tube back to its input in such
a manner that the signal would again be amplified,
fed back to the input, and so on, around and around.
The process was controlled to stop just short of
oscillation, at which point exceptionally high amplifi-
cation was achieved.
..splendid performance at a price that revolutionizes the whole world of radio
" What's the Score! Tune in with Philco Junior. It brings you
the great Fall Broadcasts - football and election news"
"New balanced superheterodyne with fine tone, surprising
distance - Bargain price"
"the tone of Philco Jr. is superb. Its selectivity and distance is
surprising. Here's a balanced Superheterodyne with genuine
Electro-dynamic Speaker, illuminated station dial, New Philco
High-Efficiency tubes - truly a radio which proudly bears the
name of Philco. And it's in a Baby Grand cabinet of unusual
beauty and graceful design"
the great Fall Broadcasts - football and election news"
"New balanced superheterodyne with fine tone, surprising
distance - Bargain price"
"the tone of Philco Jr. is superb. Its selectivity and distance is
surprising. Here's a balanced Superheterodyne with genuine
Electro-dynamic Speaker, illuminated station dial, New Philco
High-Efficiency tubes - truly a radio which proudly bears the
name of Philco. And it's in a Baby Grand cabinet of unusual
beauty and graceful design"
...only Philco could offer so much for so little.
The model 80 used the newly introduced "high-
efficiency" 6.3V tube types, with line-up:- 36
(autodyne-type oscillator/mixer), 36 (leaky-grid 2nd
detector, with regeneration), 42 (AF output
pentode) and 80 (rectifier). Schematic.
The type 36 was a new 6.3V sharp cutoff screen-
grid tube very similar to the 2.5V 24/24A tetrode
that it replaced in the Philco line-up. Furthermore,
the model 80 was one of the first Philco sets to use
the new type 42 - the first power pentode to be
indirectly heated at 6.3V ac and the first to use
cylindrical electrode construction. It would be
extensively used by Philco for a number of years,
until their switch to the Octal types in 1937.
However, even then the 42 continued forth, as it
was re-based as the type 6F6G.
efficiency" 6.3V tube types, with line-up:- 36
(autodyne-type oscillator/mixer), 36 (leaky-grid 2nd
detector, with regeneration), 42 (AF output
pentode) and 80 (rectifier). Schematic.
The type 36 was a new 6.3V sharp cutoff screen-
grid tube very similar to the 2.5V 24/24A tetrode
that it replaced in the Philco line-up. Furthermore,
the model 80 was one of the first Philco sets to use
the new type 42 - the first power pentode to be
indirectly heated at 6.3V ac and the first to use
cylindrical electrode construction. It would be
extensively used by Philco for a number of years,
until their switch to the Octal types in 1937.
However, even then the 42 continued forth, as it
was re-based as the type 6F6G.
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