Stromberg-Carlson 320 Engineering Data

Engineering Data
Stromberg-Carlson No. 320 Radio Receivers
STROMBERG-CARLSON TELEPHONE MANUFACTURING COMPANY
ROCHESTER, NEW YORK
ELECTRICAL SPECIFICATIONS
Type of Circuit_
Tuning Ranges_
Number and Types of Tubes_
Voltage Rating_
Input Power Frequency_
Input Power Rating_
Frequency of Intermediate Amplifier
-Superheterodyne
_A—530 to 1700 Kc.; C—5900 to 18,000 Kc.
1 No. 6A8, 1 No. 6K7, 1 No. 6Q7G, 1 No. 6V6G, 1 No. 80
-105 to 125 Volts, A. C.
-25 to 60 Cycles and 50 to 60 Cycles
-40 Watts
-455 Kilocycles
APPARATUS SPECIFICATIONS
No. 320-H Receiver-50 to 60 Cycles; P-28646 Chassis Assembly
No. 320-HB Recelver-25 to 60 Cycles; P-28647 Chassis Assembly
No. 320-T Receiver-50 to 60 Cycles; P-28646 Chassis Assembly
No. 320-TB Receiver-25 to 60 Cycles; P-28647 Chassis Assembly
CIRCUIT DESCRIPTION
These receivers are five tube superheterodyne receivers employing metal tubes and an efficient dynamic
speaker. There are two tuning ranges; the frequency limits of each range are listed under the "Electrical Specifi¬
cations" given above. The pilot lamp circuit is arranged so that the large tuning dial is illuminated at all times
when the receiver is turned "on".
The various tubes are used in these receivers as follows: The No. 6A8 tube functions as both Modulator and
Oscillator. The No. 6K7 tube is used in the I. F. Amplifier and the No. 6Q7G tube is used as the Demodulator,
Automatic Volume Control and Audio Amplifier tube. The No. 6V6G tube is used in the Audio Power Output
Stage and the No. 80 tube is the Rectifier tube of the power supply unit.
Fig. 1. Terminal Layout for Voltage Measurement Chart and Location of the
Various Aligning Capacitors.
NORMAL VOLTAGE READINGS
The various values of voltages listed in the following table are obtained by measuring between the various
tube socket contacts and the chassis base, with the tubes in their respective sockets. The receiver is, therefore,
in operation when the measurements are made. Figure 1, shows the terminal layout of the sockets with the
proper terminal numbers.
Voltages are given for a line voltage of 120 volts, and allowance should be made for differences when the
line voltage is higher or lower. A meter having a resistance of 1000 ohms per volt should be used for measuring
the D. C. voltages. Voltage values shown are those obtained on the lowest possible scale of a meter having the
following ranges: 0-2.5, 0-10, 0-100, 0-250, 0-500, 0-1000 volts except when an asterisk appears after any given
voltage value in which case the 250 volt scale was used.
P-28908 Issue 1 Printed in U. S. A.