The Eveready "30" Receivers
The Eveready "Model 34" Console.
The National Carbon Co.'s line of Eveready receivers presents the same chassis, the
"Model 30," in a choice of consoles. The receiver, a R.F.L. design. has variometer tuning
in the antenna circuit, and six stages, using four 27s and push-pull '71s. All console
models have the Eveready dynamic reproducer built in.
Silver A.C. Short-Wave "735"
Chassis of the "Round-the-World Six," a 17 to 650 meter factory assembled receiver.
This receiver is designed to take short-wave reception off the breadboard and into
the parlor. Its circuit is similar to that of the D.C. "735" which is also available;
the latter uses one '22 in an untuned R. F. stage, and four 12As. The A.C. model uses
a '24 with its superior characteristics in the first stage, and has a '45 push-pull output.
The audio channel and power unit are the same as in the "Model 722" - "Band Selector
Seven". The "735" A.C. model lists at $64.90, factory assembled. without cabinet or long
wave plug-in coils.
Set Tester And Checker
The Weston "Model 533" Counter Checker.
Thirteen ranges are combined in the new Weston "Model 547" Set Tester, which measures
both A.C. and D.C. voltages up to 750, by means of its two selector switches. Three 3
1/4-inch meters are incorporated in the panel. The instrument, with the necessary tools
and testing accessories, weighs ten pounds and fits in a carrying case 12 3/8 x 9 x 3
3/4 inches. Its net (dealer's) price is $93.75.
The counter rube checker is adapted for operation from any standard A.C. lighting
circuit, with considerable tolerance of input voltages; and is designed to test quickly
all the latest A.C. as well as D.C. rubes for their characteristics.
Brandes And Kolster Remote Tuners
The Brandes "Model B15," with its selector tuner above. The Kolster and Brandes receivers
of this season incorporate a new method of automatically-selective tuning.
The Kolster "K-45" has no knobs or dials on the front; its dial may be seen through
a small window in the top. and the tuning buttons are on the side. In addition. there
is a remote-control box, led by a cable to the set, which has six buttons for as many
stations, volume control, switch and pilot lights. The list price of this de luxe set
is $500; other models range down to $200.
Above, the remote-control tuning box of the Kolsrer "K-45;" at the left, the automatic
selector built into the set itself.
By modern house-wiring methods, any room can be equipped with a receptacle, thus allowing
a convenient disposition of the tuning box wherever desired.
The Brandes brings the selector tuning system into a lower price range. This line
has also four tuned circuits and '45 push-pull amplification. The "Model B-15" illustrated
lists for $125.50; the line covers the field from $85 to $165.
De Forest Audions
In the line of new tubes presented by the de
Forest Radio Co., an improved heater design has been incorporated to reduce the hum of
the A. C. filament current. The heaters now used are made of "crolite," a new synthetic
ceramic; and the filament is completely shielded from the cathode. In the 410 power tube,
as in the new D.C. screen-grid audion (the 422), oxide-coated filaments are used to give
longer life than with the thoriared-tungsten commonly used. In the new 424, the A. C.
screen-grid audion, other characteristics have been retained, but the grid bias has been
The Crosley "Monotrad" in a table-type metal cabinet, designed to take the speaker
as shown or on top.
In the Crosley line of mass-production price receivers, the newest arrival is the
Monotrad, a seven-tube A.C. screen-grid receiver, listing at $62 without accessories.
Its chassis, illustrated below, has the new Crosley triple-range control, a completely-shielded
gang condenser carbon-type amplification control and Mershon condenser. It is intended
for use in any of the many cabinets designed for the Crosley line.
The chassis of the Crosley "Monotrad."
Majestic Receiver Models
The post-colonial console design of the "Model 181."
The Majestic line incorporates, in its "Models 91 and 92," the latest type of power
detection. These receivers, with built-in super-dynamic reproducers, list at $137.50
The "Model 181," illustrated above, is a striking accomplishment in cabinet work,
and reproduces either radio or phonograph records through a '50 push-pull amplifier.
Zenith Remote-Tuner System
The Zenith "50 Screen-Grid" Chassis (above) and Automatic Tuner (below, right).
The newest Zenith designs Incorporate
the "Model 50" chassis, with its five tuned R.F. circuits, and two push-pull audio stages,
with '45 output. All embody the Zenith automatic tuning system, to which has just been
added (in the "Model 55") the remote tuner illustrated. This operates at the turn of
a button, its pilot light automatically indicating the station which is on; and gives
also volume control. The set operates a 12·inch dynamic reproducer. The "Model 55" is
priced at $700 in its Italian Renaissance cabinet; others down to $175.
Champion Radio Tubes
A new method of merchandising of interest to
buyers, as well as sellers, is utilized in the packing of Champion tubes. Not only is
there the new system of packing the complete tube equipment for a given receiver in one
carton; but the individual tube is in a stout container of a design which permits a demonstration
test of its characteristics without removing it or breaking the seal by means of a test
adapter furnished by the manufacturers.
Hammarlund Amplifying Units and Transformers
The Harnmarlund Manufacturing Co. has just added to its extensive list of radio components
several important units; among them a three-stage R.F. band-selector, known as "BS-3,"
to work ahead of an amplifier; a three-stage screen-grid R.F. amplifier, "RF-3," to follow
the former; a shielded, polarized R.F. choke, SPC, and a family of audio-frequency transformers.
The band filter comprises a three-gang "Midline" condenser and matched filter coils;
this affords pure 10-kc. selectivity ahead of the amplification. The amplifier also contains
a three-gang condenser and matched, shielded coils. Both units are factory assembled
In front, the "Battleship" condenser of the band filter; behind it, the coils in their
The first-stage A.F. transformer, "AF-2," has a ratio of 1 1/2-1; the push-pull input
type, "AF·4," 2-1 on each side. Both have very large primaries, and cores of special-alloy
laminations to insure a flat characteristic. The output transformer types are "AF-M"
for magnetic reproducers and "AF-D" for dynamics.
A complete power supply unit, "PS-45," is designed to operate a receiver with push-pull
'45 amplification. It comprises two heavy chokes and a power transformer with primary
tapped at 80 volts for use with an automatic voltage regulator. The high-voltage secondary
is a center-tapped 750-volt winding with a rating of 100 milliamperes; and there are
a 5·volt and two 2 1/2·volt windings. The new voltage divider is "RHQ-30" and the condenser
The new A.F. transformer in its steel housing for sub-base mounting.
Jewell "581" Test Panel
The Jewell Electrical Instrument Co. has designed a laboratory panel, suitable for
shop or jobber's use, to facilitate complete testing of receivers and other radio apparatus
in the shortest time. It is furnished with high-resistance precision meters and gives
in addition to tube readings, condenser capacities and high-voltage secondary readings.
Dealer's price $159; with work bench, $208.87.
Readings of the seven large (5 inch) meters of the Jewell Test Panel are visible at
a glance. It is a time-saver; and time is money, even in the radio business. There is
a tube socket at the lower right for testing rubes apart from a set.
"General" Wood Cabinets
The increasing vogue of individuality, in cabinets to take standard receiver chasses,
has promoted the production of many very artistic designs. The Wood Cabinet Corporation
presents a line, of which the "Model 108" is illustrated; it is designed to accommodate
any popular set, with speaker above.
An attractive and somewhat modernistic piece of cabinet work.
Best Electric Motor Chassis
The "BBL" electric motor, designed for small-cone reproducers, incorporates a tapped
winding with a switch, which matches the output impedance of the receiver without resorting
to a special transformer, as well as a separate volume control. It is now available in
a separate cabinet, at $35 list, as well as in chassis form at $22.50.
The magnetic reproducer unit of the "BBL" motor will drive a 12-inch fixed-edge diaphragm.