Emerson 540A (540) "Emersonette" Midget Radio (1947)
The Emerson model 540/540A, introduced in
early 1947, features a tiny cabinet housing an
All-American-Five (AA5) AC/DC superhet tuning
the standard broadcast band. It was offered in
a choice of four different colors of plastic:-
walnut bakelite, ivory plaskon, red plaskon and
mint green plaskon. All had black bullet style
knobs. The 540 was advertised as "the world's
smallest ac/dc superhet" and in walnut it had an
original list price of $19.95. Other colors were
priced $5 more at $24.95.
The cases are very fragile and as a result
relatively few have survived. Today, the 540 is
highly collectible and the red and green ones in
clean, undamaged condition can command a
price that runs into four figures!
Frequency coverage is from 540 -1620kc. The
540 uses the AA5 minitaure tube complement:-
12BE6 (mixer/LO), 12BA6 (IF amp), 12AT6
(2nd detector/AVC/1st AF), 50B5 (AF output)
and 35W4 (rectifier). 540A Schematic.
The 540's styling is very similar to the pre-war
Emerson CF-255 from 1939. However, due to
the larger tube technology available back at
that time, the CF-255 had to make do with just
The rear of the cabinet
has a cardboard back
that bows out to accom-
modate a loop antenna.
...the world's smallest ac/dc superhet...
...a handful of power and miracle tone...
...a small thoroughbred in every radio respect.
540 or 540A?
The Rider's manual has three pages for the
model 540A (17-19, 17-20 and 17-21 for chassis
120042A) and three additional pages for the 540
(18-7, 18-8 and 18-9, shared with models 564
and 572, for chassis 120042). The two chassis
appear to be the same, other than changes to a
few part numbers, such as the second IF trans-
former. The cases, dials, knobs, etc. are identical
between the models, with the sole exception that
the cabinet parts list for the 540 includes a black
bakelite cabinet in addition to the red, green,
walnut and ivory offered for the 540A. I have never
seen the black cabinet, nor have I found any
advertising that mentions it. The 540 probably
preceded the 540A, even though its Riders pages
appear in a later volume (18 versus 17 for the
540A). All advertising I found simply refers to the
set as "model 540".
This all leads me to conclude that there is little
practical difference between the models from a
user's or modern collector's perspective. Note
that the model number is stamped on the rear
cover. However this is indecipherable on all but
one of my sets.