Stromberg-Carlson 337 Engineering Data

Engineering Data
Stromberg-Carlson No. 337 Radio Receivers
STROMBERG-CARLSON TELEPHONE MANUFACTURING COMPANY
ROCHESTER, NEW YORK
ELECTRICAL SPECIFICATIONS
Type of Circuit_
Tuning Ranges_
Number and Type of Tubes-
Voltage Rating_
Power Frequency Rating_
Input Power Rating_
Frequency of Intermediate Amplifier
_Superheterodyne with Electric Tuning
_53 to 1.7 Me.; 2.25 to 7.6 Me.; 7.6 to 23 Me.
1 No. 6K8,1 No. 6K7,1 No. 6H6,1 No. 6F5,1 No. 6F6G, 1 No. 6U5,1 No. 80
_105 to 125 Volts
_25 to 60 Cycles and 50 to 60 Cycles
_70 Watts
_455 Kilocycles
APPARATUS SPECIFICATIONS
No. 337-H 50 to 60 Cycles; P-29588 Chassis Assembly;P-27557 Speaker
No. 337-HB_25 to 60 Cycles; P-29589 Chassis Assembly; P-27557 Speaker
No. 337-L 50 to 60 Cycles; P-29588 Chassis Assembly; P-27605 Speaker
No. 337-LB _25 to 60 Cycles; P-29589 Chassis Assembly; P-27605 Speaker
CIRCUIT DESCRIPTION
These receivers are seven tube, instantaneous "Electric Tuning" superheterodyne receivers employing metal
tubes and an efficient dynamic speaker. There are three tuning ranges, the frequency limits of each range being
listed under the "Electrical Specifications", given above.
The electric tuning circuit is arranged so that six favorite stations located in the Standard Broadcast range
may be set up for instantaneous selection by means of the push buttons. (Local and other stations that give the
best daytime and evening service should be selected.) To properly set up the electric tuning arrangement for
the six favorite Standard Broadcast stations, read the section, "Instructions for Setting Up the Electric Tuning
Arrangement", appearing on page 4 of this book. Manual or electric tuning for the Standard Broadcast range
is easily obtainable by simply rotating the Range Switch control knob so that the arrow on the knob points in the
direction of the designation for the desired type of tuning. When manually tuning the receiver in either the
Standard Broadcast or Short Wave ranges, the electric tuning arrangement is made inoperative and the dial of
the receiver is illuminated. When the Range Switch control knob is set for electric tuning (arrow on Range
Switch control knob pointing in direction of the star), the dial illumination ceases and the station letters of the s.
six stations which are set up for electric tuning become illuminated. When manually tuning these receivers or
when setting up the six desired stations for electric tuning, resonance with a signal is indicated by means of the
tuning indicator tube which operates on the cathode-ray principle.
A special temperature controlled compensating capacitor is used in the oscillator circuit of these receivers
when operating the electric tuning arrangement in order to eliminate drift in the oscillators frequency. These
receivers are also provided with a low level bass frequency compensating circuit in conjunction with the volume
control circuit so that balanced reproduction is obtained for any setting of the volume control.
The various tubes are used in these receivers as follows: The No. 6K8 tube functions as both Modulator and
Oscillator tube. The No. 6K7 tube is used in the I. F. Amplifier and the No. 6H6 tube is used as both Demodu-
Fig. 1. Terminal Layout for Voltage Measurement Chart and Location of the
Aligning Capacitors,
P-30011 Issue 1 Printed in U. S. A.