The Collins KW-1 Transmitter is engineered to equip the amateur for use of the absolute maximum power permitted by his license. This transmitter is the result of years of advanced planning and design — a unit you can be proud to own and operate. With the Collins KW-1 you can work dx you’ve never reached before. The KW-1 is a vfo controlled, bandswitching, gang tuned, phone and cw transmitter. Its input is a full 1000 watts on the 80, 40, 20, 15, 11, and 10 meter bands and 500 watts on the 160 meter band. The entire transmitter together with its power supply is enclosed in a handsome grey, wrinkle-finish cabinet.


The KW-1’s frequency range covers 160, 80, 40, 20, 15, 11, and 10 meter bands. Complete bandswitching of the exciter, driver, and power amplifier is accomplished by a single control on the front panel. This reduces to four the number of tuning functions required in operation: bandswitch selection, frequency setting, PA tuning, and PA loading. Over any narrow frequency range, it is only necessary to adjust the frequency control, which is by means of a recently developed, extremely stable, hermetically sealed master oscillator.  Below: KW-1 RF Deck..


The design of the KW-1 Transmitter is such that spurious radiation has been reduced to a very low value, particualarly on television frequencies. The r-f unit is completely shielded i a metal box inside the main cabinet. All circuits passing through this shield are wll filtered for attenation at television frequencies. These features minimize direct radiation from the cabinet and external leads. In the power amplifier the use of a pi section followed by an L section very effectively reduces harmonics of the carrier frequency. To this is added the attenuation of the 35C-2 Low Pass Filter.


Oscillator – two 6BA6’s. Exciter — one 6BA6, four 6AQ5’s, one 807W, two VR105’s, one 6A10 ballast tube. Power amplifier — two 4-250A’s. Speech amplifier — one 12AX7, one 6AL5, two 12AU7’s, two 6B4’s, two 810’s. Rectifiers — two 872’s, one 5R4GY and three 5V4’s.


Modulation current, PA plate current, high voltage, line voltage, multipurpose meter, antenna ammeter. Line fuses, plus overload relay in Class C amplifier current lead, provide circuit protection.

Power Amplifier Input         1000 watts (500 watts on 160 meters)

RF Output Impedance         52 ohms

Maximum Permissable       2.4 to 1
Standing Wave Ratio

Amateur Bands Covered    160, 80, 40, 20, 15, 11, 10 meters

Frequency Range                1700-2000 kc
3400-4100 kc
6700-8200 kc
13,400-16,400 kc
20,100-24,600 kc
26,800-32,800 kc

Emission                              Voice or cw

Frequency Control               70E-14 Master Oscillator, 1675 to 2050 kc

Microphone Input                 Will match high impedance dynamic or crystal

Phone Patch Impedance     600 ohms, unbalanced to ground

Weight                                 600 pounds

Dimensions                          66 1/2″ high, 28″ wide, 18″ deep

Circuit Protection                Overload relay, fuses, high voltage arc gaps

Tuning Controls                   Bandswitching, frequency selector, PA tuning, PA loading

Other Controls                     Filament switch, filament voltage adjustment, plate switch,
overload reset switch, overload relay adjustment, send-
standby-calibrate switch, emission selector switch, tune-
operate switch, meter switch, power amplifier excitation
control, modulator bias control, audio driver bias control
clipping level, audio gain control, bandspread adjustment.

Accessories Required         High impedance microphone, telegraph key, 52 ohm antenna,
wiring to power source.

Power Source                     230 v, 3 wire, 50/60 cycle, single phase, grounded neutral;
or 115 v, 2 wire 50/60 cycle, single phase.

Typical Power Demand,      Key Closed                  2000 w
CW                                       Key open                       800 w
Calibrate, key closed      660 w
Standby                         500 w

Typical Power Demand,      100% sine wave mod.    3100 w
Phone                                  No modulation               2280 w
Calibrate                         780 w
Standby                          600 w

Net Domestic Price*           $3850.00

                                                        * From 10-53 brochure      Courtesy of Gary – WA9MZU