April 1932 Radio-Craft
[Table
of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Craft,
published 1929 - 1953. All copyrights are hereby acknowledged.
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This Radio Service Data Sheet for the Kennedy
Superheterodyne Short-Wave Converter is an example of the dozens of similar schematic and
alignment instruction sheets that have been posted on RF Cafe over the years. Obtaining technical
information on most things, even readily available items, prior to the Internet era was often
very difficult - if not impossible. Service centers had what was need provided by manufacturers
and distributors, but if you wanted to find a part number or service data on a refrigerator,
radio, lawn mower, garage door opener, etc., and did not have the original paperwork, you
were usually out of luck. Nowadays a Web search will quite often get you what you need thanks
to people (like me) who go to the trouble of making the information
available. The stuff doesn't just magically appear or get posted by benevolent governmental
entities. You're welcome.
Kennedy Superheterodyne Short-Wave Converter Radio Service Data Sheet
Short-wave converters and receivers have recently been sold in such large numbers as to
require the expert attention of the average Service Man. The Kennedy Model 54 Converter, manufactured
by Colin B. Kennedy Corp., South Bend, Ind., for instance, contains numerous points of ·particular
interest to Service Men who previously have only attended to the peculiarities of standard
broadcast receivers.

(Model 54 "Globe Trotter")
The Model 54 converter operates on the superheterodyne principle, and therefore includes
a first-detector - a '24 tube, and an oscillator - a '27. Filament power is obtained from
a built-in transformer; the "B" potential is obtained from the standard broadcast receiver,
which also furnishes the remaining portions of the superheterodyne circuit - that is, the
I.F. amplifier, second-detector, audio amplifier, main power pack; the "C" potentials are
derived in the usual manner-as the potential across cathode resistors.
Of course, some broadcast receivers may already incorporate superheterodyne circuits. In
such instances, the combination of converter and receiver constitutes a "double superheterodyne,"
in which the converter's tube arrangement would be referred to as first-detector V1, and first-oscillator
V2; and the subsequent tubes in the broadcast receiver then will be designated, respectively,
as: first R.F.; second-detector; second-oscillator; I.F. amplifier; third-detector; and audio
amplifier.
Parts replacement values: Resistor R1. 10,000 ohms; R2, 400; R3, 25,000; R4, 50,000; R5,
5,000. Condenser C, oscillator tuning; C1, main tuning; C2, I.F. trimmer; C3, C4, 0.1-mf.;
C5, C6, 0.25-mf.
The plate current obtained from the standard broadcast receiver for operation of the converter
is very slight, and adds no noticeable burden to the power supply of most sets. Two wires,
for supplying this power, come out from the side of the short-wave unit, and are to be connected
to the long-wave (broadcast band) set. One is a black lead which is connected to the "ground"
binding post on the long-wave set; the other is a red lead, which is connected to the negative
side of the reproducer field coil (dynamic reproducer), to the speaker wire or connection
carrying a filtered "B" supply, or (inside the chassis) to the positive end of the voltage-divider
resistor.
Any source of "B" voltage from 150 to 250 volts is suitable. It should be obtained from
some point in the long-wave receiver speaker or filter system, where it will receive fairly
good filtering and be relatively free from hum. A lower voltage, well-filtered, is more to
be desired than a higher voltage with a large proportion of A.C. modulation.
Obtaining this plate supply is very simple on many receivers, such as the Kennedy Models
210, 310, 220, 320, 1030, 632, 426, 526, 726, and 826. In these, the "B" supply may be taken
from the tip-jack terminating the black speaker wire. In Kennedy Models 42, 50, and 52, it
may be obtained at the speaker terminal panel from the side of the field winding which is
common with the speaker-transformer primary. Similar points for connection, on other makes
of receivers, are usually located without any difficulty. The correct terminal may usually
be quickly found by testing from chassis, or ground, to the various speaker terminals. It
should rarely be necessary to go inside the chassis to find a source of "E" power.
If difficulty is had in getting the unit to operate when initially hooked up, and the "B"
source is suspected, 90 to 135 volts of "B" batteries may temporarily be tried. The red wire,
of course, goes to the plus "B" lead, the black wire to the long-wave receiver ground post
as before, and the negative "B" lead to the same ground post.
The antenna and ground wires are entirely disconnected from the long-wave receiver. They
are to be connected to the posts marked "antenna" and "ground" of the short-wave unit, and
left there permanently.
A wire is also connected from the antenna post of the long-wave set to the binding post
on the rear of the short-wave chassis marked "L.W. Ant." This wire should be as short as practical
to lessen any chance of broadcast stations being picked up and heard in addition to the short-wave
signals.
It will be noted, facing the rear of the chassis, that on the left-hand side a wire has
been brought out which may be connected to either one of two small binding posts near the
end of the base. The purpose of this is to adjust the output impedance of the unit L2 to that
of the antenna input circuit of the receiver with which it is to be used. The Kennedy models
previously mentioned have "high impedance" antenna circuits and therefore require this wire
to be on the upper binding post. In doubtful cases, this wire may be tried first on one and
then on the other, with the unit operating, and permanently left where best results are obtained.
These connections are indicated on the diagram and the photographic illustration.
The output of the short-wave unit is tuned. It is set, at the factory, for best operation
at about 1,525 kc. Naturally, the long-wave receiver dial must be set at this point for short-wave
reception, and left there. The R.F. portion of the long-wave receiver becomes the I.F. tuner
and amplifier of the "short-wave superheterodyne." Just past 1,500 kc., a point easily reached
on almost all broadcast receivers, has been found most desirable. The volume control on the
long-wave receiver also acts as the volume control for short-wave reception; while finding
stations, this control is to be turned full on.
In the event the long-wave receiver will not tune past 1,500 kc., or a strong local broadcast
station interferes at that point, the output frequency tuning may be altered slightly to avoid
the difficulty. An adjusting screw for this tuning may be reached through a hole in the rear
of the chassis. It is located near the impedance adjusting wire and binding posts, and is
to be adjusted with an insulated screw driver.
Set the main band-selector switch SW.1 on the position marked "15-25 meters," tune in a
station (music or code) at about 50 on the right-hand dial. Then adjust the screw described
until the left-hand dial also reads approximately 50 when correctly tuned in. This adjustment
then holds for all wave-bands.
For best results, particular care should be taken in the installation of the antenna for
short-wave reception. For instance, it should be clear of metal and grounded objects; and
its lead-in should not be enclosed in metal conduit. Also, the antenna and ground leads should
not be twisted together, or run tightly parallel for any considerable distance.
The right-hand dial of the short-wave unit (looking at the front of the instrument) might
be termed the "station-finding dial," operating variable condenser C. It should be adjusted
very slowly in order not to pass over the signals of the desired station. At the same time,
the left-hand knob, controlling variable condenser C1, should be rotated so that the dials
read approximately alike.
Posted August 7, 2015
Radio Service Data Sheets
These schematics, tuning instructions, and other data are reproduced from my
collection of vintage radio and electronics magazines. As back in the era, similar
schematic and service info was available for purchase from sources such as
SAMS Photofacts, but these printings
were a no-cost bonus for readers. There are 227 Radio Service Data Sheets as of
December 28, 2020.
-
National Union "Presentation" Radio Model G-619
-
Zenith Radio Models 8H032, 8H033, 8H050, 8H052, 8H061
-
General Electric Farm Radio Model 280
-
Admiral Model 6RT44-7B1
-
Montgomery Ward Airline Model 04BR-1105A Radio
- Belmont
Model 678 Auto-Radio Set
- Sentinel
Model 217-P Portable Radio Set Radio
- Remler
Model No. 36 Dual-Wave Auto-Radio
-
Stromberg-Carlson No. 82 All-Wave Receiver
-
Majestic A.V.C. Model 290 Chassis
- FADA 9 Tube
Model 190 "Metal" All-Wave
- RCA Victor
Models 9T and K2 9-Tube, 5- to 566-Meter
-
Motorola "Golden Voice" Model
-
RCA Victor Model H-6
-
Simplex Model TA
-
Automatic "Magic Eye" Model A1
- Silvertone
Models 4488 and 4588 (Chassis No.101412) and 4488A and 4588A (Chassis No. 101412A)
- RCA Victor
Model M109 "De Luxe" 7-Tube Auto-Radio Receiver
- Crosley Model
6625 6-Tube 3-Band Receiver
- International
Model 77 Series 7-Tube Dual-Band Receiver
- Belmont
Model 6D121
-
General Electric Models 60, 62
- Admiral
Model 7C64
-
Radiola "28" Super and "104" Power Speaker
- Sonora
Model TW-49
-
Stromberg-Carlson Models 1020, 1120, Series 10
- Air King
Model 4604D
- Sparton Models
526, 526X, 526PS
- Truetone
Model D2624
- Admiral
Models 6EI, 6EIN
- Detrola Models
571A, 571B
-
General Electric Model 250
- Howard Model
920
- Colonial
Model 652 5-Tube Broadcast-Short-Wave
-
Fairbanks-Morse
9-Tube All-Wave Model 91
-
International Model 500 5-Tube Dual-Range Battery
- Emerson Model
678 "Auto-Dynamic" 5 Tube
-
Stromberg-Carlson
Nos. 230 and 231 Series
- Atwater
Kent Model 649 All-Wave
-
Howard Model G-26, and "Airplane 4" Model AA25
-
Montgomery Ward "Airline" Series 7GM 7-Tube High-Fidelity Receiver
- RCA
Victor Model T5-2 5-Tube, 2-Band A.C. Superheterodyne Receiver
-
Majestic
"Models 50," "51" and "52"
-
Bremer-Tully Model 7-70 and 7-71
-
General
Electric Model M-49 4-Tube Radio-Phonograph Dual-Wave Superheterodyne
- RCA-Victor
Radiola "Superette" Model R7 Superheterodyne
- Crosley Model AC-7
and AC-7C
-
Westinghouse
"Columnaire" Models WR-8 and WR-8-R (Remote Control)
-
Characteristics
of Metal Tubes - and Other "Octal" (8-Prong) Base Types
- Kolster K20,
K22, K25, K27 and K37 Six-Tube Receivers
-
Stromberg-Carlson
Nos. 62 and 63, 8-Tube High-Fidelity Chassis
- RCA Model
103, 4-Tube A.C. Compact Dual-Wave
- FADA "Special"
Model 265-A and FADA "7" Model 475-A
-
General Electric Model C-62 6-Tube Battery
- Emerson
5A Automotive
- Zenith
666 Automotive
- Motorola
100 Automotive
-
Crosley
Roamio 4-A-1 Automotive
-
American-Bosch
524A Automotive
- Crosley
Model 1316 (in Model 167 Console)
- RCA Victor
"High-Fidelity Electrola," Model R-99
- AMRAD
Model 81 ("Bel Canto" Series) Receiver
-
Fada 103 Fadalette, Stewart-Warner Series 108, DeWald 54 Dynette Sets
- RCA
Victor R-27 and Philco 53 Ultra-Midget A.C.-D.C. Radio Receivers
-
Majestic Models Fairfax and Sheffield 8-Tube
- Stromberg-Carlson
No. 29, 9-Tube Superhet
-
International Kadette Model 400 4-Tube Battery-Operated Superhet
- RCA Victor
Model 5M 5-Tube Auto Superhet
-
Majestic Model 11 Short-Wave Converter
-
Silver-Marshall
Model 727-DC Battery-Operated Superheterodyne
- RCA
Victor Model VHR-307 Home Recording - Phono-Radio Combination
-
Delco 32-Volt Radio Receiver Chassis Models RA-3, RB-3 and RC-3
- Majestic
Chassis Models 380 A.C. T.R.F., and 400 A.C.-D.C. Superheterodyne
- General
Motors S1A, S1B
- Admiral
Model 7C63, Chassis 7C1
- Westinghouse
Model H-133
- Arvin
Models 150TC, 151TC
- Kadette Model
90 Duplex
-
RCA-Victor "Magic Brain" Model 281
- Grunow
11A Chassis 11-Tube All-Wave Superheterodyne
-
Sears, Roebuck & Co., Silvertone "Rocket" Models 6110 and 6111
-
General Electric Model GD-52
-
Zenith Models 6D302, 6D311, 6D326, 6D336, 6D360
-
Allied Radio, Knight Model E10913
- Arvin Model
140P
- Emerson
Models 501, 502, 504
- Crosley
Model 56TD-W
- Hoffman
Model A500
-
Stewart-Warner
Model 9003-B
-
Zenith Models 6D014, 6D029
- Coronet
Model C-2
- Sparton
Models 7-46, 7-46PA, 8-46, 8-46PA
-
Stewart-Warner Models 9001-C, D, E, F
-
Zenith Models 5D011-5D027
- Bendix Models
636A, C, D
- ECA Model 108
-
International Model 66 and 666, 6-Tube Superhet
-
Ford-Philco
Radio, Model FT9, 6-Tube Auto-Radio Receiver
- Howard
Explorer Model W Deluxe 19 Tube All-Wave Superhet
- RCA Victor
Portable Table Electrola Model R-95
- Atwater
Kent Model 305Z 5-Tube 32 V. D.C. Superhet
- Kadette
Jewel Model 40 Chassis 3-Tube Ultra-Midget Receivers
-
General Electric Model N-60 6-Tube Auto Superheterodyne
-
Sparton Model 40 6-Tube T.R.F. Automotive Receiver
-
Clarion "Replacement" Chassis, Model AC-160 A.V.C. Superheterodyne
- Emerson Models
20A and 25A
- General
Electric K-40A
- Pilot Model
B-2
- RCA-Victor
Radiola Model M-30 Automotive Radio
- Motovox
Models 10A All-Electric and 10E Battery-Operated "Moto-Tetradynes"
-
Kennedy Superheterodyne Short-Wave Converter
- RCA
Victor Model R-78 B1-Acoustic 12-Tube
- Philco
Model 15 Series, 11-Tube Superheterodyne Chassis
-
Zenith Challenger Model 740
-
Sparton
Selectronne Receivers Models 1068 and 1068X
- Fada Model
155 Super Fadalette A.C.-D.C. Set
-
Clarion De Luxe Models AC-280 and 25-280
-
Crosley Model A-157 (River Roamio) Auto Radio
- Philco Model
'37-116 Codes 121 (Shadometer) and 122 (Dial Tuning)
-
Arvin Model 28
-
Philco Model 818
-
Fada Model 266 Motoset
-
Bosch Models 736, 737, 738
- RCA-Victor
Model 15U, Radio-Phonograph
- Sparton
Models 566 ("Bluebird" Mirror), A.C.-D.C. 5-Tube 2-Band Midget Superhet
- Atwater
Kent Model 776 6-Tube Auto Radio
- Stromberg-Carlson
No. 61 4-Band 7-Tube A.C.-D.C. Receiver
- Arvin Model
182TFM
- Crosley
Model 58TK
- Westinghouse
Model H-165
-
General Electric Models G-105 and G-106
- Silvertone
"F," "FF," "G," "H," and "J"
-
Stewart-Warner Model 03-5A1 to 03-5A9 (Chassis 03-5A) Senior Varsity Radio
- Radiola Models
61-6, 61-7
-
Westinghouse
Models H-104, H-105, H-107, H-108
- Farnsworth
Models EC-260, EK-262, EK-263, EK-264, EK-265
-
United
Models 980744, 980745
-
Stewart-Warner (R-127 Chassis) Models 1271 to 1279 All-Wave
- ERLA Model
4500 Dual-Wave T.R.F. 4-Tube A.C. Receiver
- Clarion No. TC-31
5-Tube A.C.-D.C. Superhet.
- Detrola Model
105C 5-Tube Dual-Band A.C.-D.C.
- Zenith
6-Tube All-Wave Chassis No. 5634
- RCA Victor
Model 261, 555 to 107 Meter
- Philco
Model 38-116; Code 125
-
Stewart-Warner "Ferrodyne" Chassis Model R-136
-
American-Bosch
Model 43OT 5-Tube 3-Band Superheterodyne
- RCA
Victor Model C9-4 9-Tube 3-Band Superheterodyne
- Kennedy "Model
826B" Combination Receiver
- Steinite
50-A and 102-A
- Pilot Model
63 All-Wave 6-Tube Superheterodyne
- Stromberg-Carlson
No. 69 4-Tube All-Wave Superhet. Selector (Converter)
- RCA
Victor Model 102 4-Tube A.C.-D.C. T.R.F. Receiver
- Bosch Models 60
and 61
-
Atwater Kent Models 30, 33, 35, 48 and 49
- Crosley Model
120 Senior Superheterodyne (Pliodynatron) Chassis
-
Columbia Screen-Grid 8 Receiver
-
General Electric Models A82 and A87, 8-Metal-Tube All-Wave A.C. Superhet.
- Colonial
31 and 32 D.C.
- Zenith 5-Tube
Triple-Wave Chassis nos. 5508 and 5509
- Remler Model
46 ("Scottie")
- General
Electric FA-60 and FA-61
-
Stewart-Warner
Series 900
-
Howard
Model B-5 (715), Series 1 and 2 (Sheaffer Radio-Clock-Pen Desk Set)
-
Ford-Philco Car-Radio Models F-1440 and F-1442
-
Brunswick Model 31 Combination Radio and Panatrope
- Emerson Models
38, 42 and 49, 6-Tube Dual-Wave (Chassis U6)
-
General Motors Chevrolet No. 601574 Automotive
-
RCA Victor M-104 (and M-108) Automotive
- Arvin-Ford
17-A Automotive
-
Westinghouse Model WR 207 & WR 208 5-Tube Dual-Band Superheterodyne
- Radiolas
"Super VIII" (AR-810, "Semi-Portable" (AR-812), 24 and 26
- Howard Model
45 A. V. C.
- Majestic
Model 25
-
Galvin Motorola Model 61
-
Arvin Model 6
- Admiral
Models 7T06, 7T12
- Garod Model 5A1
- Hoffman Model A301
-
Knight Model E10716 Battery Portable
- Arvin Models 555,
555A, 552N, 552AN
- Grantline Models
605, 606
- Truetone Model
D2616
- Belmont Model
5D128
- Arvin Models 444,
444A
-
International Kadette Model 1019
-
Stewart-Warner Models 97-561 to 97-569
- General
Electric Model 280
- Zenith Models 5R080,
5R086
- Truetone Models
D1747, D1748
-
Crosley Roamio Automotive T.R.F. Models 90, 91, 92
-
Crosley Roamio Automotive Superheterodyne Models 95, 96
-
Wells-Gardner Series 062
-
Emerson
Model AZ-196
- Belmont Model
5P19
- Crosley Model
56FC
-
Emerson
Models 507, 509, 518, 522, 535
- Garod Model 6AU-1
- General
Electric Models 219, 202, 221
-
Crosley "Chairside" Model 567
-
Belmont Model 408 Battery "Farm"
- Wards Model
74BR-1055A
- Farnsworth
Models EK-081, EK-082, EK-083, EK-681
- Philco
Model 200-X Radio
-
Admiral "Aeroscope" Models 161-5L, 162-5L and 163-5L
- Philco
Model 59, 4-Tube A.C. Midget Superheterodyne
- Zenith
Farm Model 6V 27, 6-Tube Superhet
- Ward 10-Tube
All-Wave High-Fidelity Superhet, Series ODM
-
Philco-Packard
Deluxe
-
Canadian
Westinghouse Model 175
- Crosley Model
1155
- Philco Models
39 and 39A
-
Arvin Model 35 8-Tube Car-Radio
- Hetro
Air-Ace Series M
- Westinghouse
Models H-161, H-168, H-168A
- Garod Model 5A4
- Arvin Models 152T,
153T
- Belmont Model 5240
- Mantola Models 92505,
92506
- General Electric
Models 102, 102W, 107, 107W, 114, 114W, 115, 115W
- Crosley Model
555 (A.F.M.)
- Crosley Model
515 (Fiver)
- Crosley Model
425 (Travo)
-
Firestone-Stewart-Warner Model R1332
- Fairbanks-Morse
Model 81 "Farm" Set
- Clarion Model
423, 470, 471, 472, 480
-
International Radio Corp. Model 90
- Belmont Model
578 Series A
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