|For 1936, RCA Victor upgraded their "Magic Brain" to use three of the new
metal tube types. The original "Magic Brain" introduced the previous season
used just two tubes, with the operations of mixer and Local Oscillator (LO)
accomplished by a type 6A7 pentagrid converter. The new version used
separate tubes for the mixer (6L7) and LO (6J7). This was common practice
by many other manufacturers, particularly for their higher end all-wave
receivers where the separated mixer and LO functions resulted in generally
improved performance, especially for short wave coverage.
RCA also introduced the "Magic Eye" (type 6E5) for the 1936 season. This
was used on several of their higher-end console models, including the model
C11-1, whose chassis was otherwise the same as for their T10-1 table
model. For some reason none of their table sets for 1936 used the magic
eye - that would have to await the following season (see my 10T page).
Click on the thumbnail to the left to see an RCA advertisement for the 1936
Magic Brain, Magic Eye and Metal Tubes. An ad for the 1934/35 original
"Magic Brain", as used in models 128 and 143, can be viewed here.
|"Just as the original Magic Brain set new standards of
shortwave reception, so does the new, improved Magic
Brain achieve still higher standards..."