75A-4 / KWS-1 Accessories

[75A-4 / KWS-1 Station]

SC-101 Station Control

The SC-101 provides the necessary control functions which, with the necessary antennas and the KWS-1/75A-4 combination, will equip a complete, neat amateur station. In addition to providing the necessary interconnecting harness, the SC-101 contains a beam direction indicator, beam rotation control, phone patch, directional RF watt-meter and remote control for antenna selection. The SC-101 is composed of these units:

The 312A-2 includes a 10" speaker, beam direction indicator, directional wattmeter, 24 hour numeral clock, Lumiline lamp, phone patch, power supply for operating relays and terminal board for interconnecting units. Controls on the front panel are a three-position beam control - CCW, OFF and CW; Phone Patch VOX Balance; Phone Patch OFF-ON; Antenna Selector - X, 80, 40, 20, 15, 10; Directional Wattmeter Control - Forward 100, 1000, Reflected 100, 1000; and an ON-OFF switch with indicating light. The Antenna Selector will provide control of any three antennas. Three additional antennas may be controlled with the addition of three relays for which space has been provided. One or two rotators may also be selected in combination with the antennas. One synchro transmitter for tower mounting to feed the beam direction indicator is included with the SC-101. The synchro receiver is an integral part of the direction indicator.

The 68Y-1 mounts in any convenient position near the station. It contains the antenna transfer relay, two coax relays for antenna selection, mounting bracket for the directional wattmeter coupler and necessary interconnecting coax cables. Space is provided for mounting three additional coax relays.

The 534A-1 includes a metal duct which mounts on the rear of the desk or table and houses all interconnecting cables. Utility AC outlets are provided along the top of the duct. Included is a cable harness for interconnecting the 75A-4/KWS-1, 68Y-1 and 312A-2. Additional standard conduit will be needed in lengths depending on the individual station installation.

189A-2 Phone Patch

This unit provides the necessary apparatus for phone patch operation with the KWS-1 and 75A-4 (or KWM-1). It utilizes a hybrid transformer for proper VOX operation. Output impedance is 600 ohms. Terminal connections are provided on the KWS-1/75A-4 (and KWM-1). Two connections to phone line are all that are necessary. Space for mounting is provided in the 312A-1. The 189A-1 components are a part of the SC-101 and 312B-2 (KWM-1).

35C-2 Low Pass Filter

Collins 35C-2 Low Pass Filter is a 52-ohm three-section low pass filter with approximately 0.2 db insertion loss below 29.7 mc and approximately 75 db attenuation of harmonic emissions at TV frequencies.

Mechanical Filters

Collins F455J Series Mechanical Filters are available as accessories for the 75A-4 Receiver. The F455J-05 Filter, bandwidth of 500 cycles, is recommended for CW reception; the F455J-15 (1.5 kc) for RTTY; the F455J-60 (6.0 kc) for AM where interference is not a problem; and the F455J-21 (2.1 kc) and F455J-31 (3.1 kc) for SSB. The F455J-31 is supplied as standard equipment in the Receiver.

307E-1 Gear Reduction Tuning Knob

Provides new ease and accuracy in tuning SSB signals. Operating on a 4 to 1 ratio, it eliminates the need for the Dial Drag control and has no detectable backlash. Simple installation on KWS-1 and all 75A models. Standard equipment on later models of 75A-4 and KWS-1.

312A-1 Speaker/270G-3 Speaker

The 312A-1 Speaker Unit includes loudspeaker and has space for the extra control functions necessary in a complete installation. Unit is furnished with removable perforated steel front panel insert with no cutouts; operator can remove panel and install any control functions such as beam direction indicators, clocks, switches, etc. A 10" speaker is sub-mounted behind the front panel and a Lumiline lamp above. Rear of the unit is open and across the bottom is a terminal strip. The 270G-3 cabinet and 10" PM speaker assembly is attractively finished to match the 75A-4 Receiver.

302C-1 and -2 Directional RF Wattmeter

This wattmeter measures forward and reflected power in a 52-ohm coaxial transmission line over the frequency range of 2-30 mc. Scale ranges of 0-100 and 0-1000 watts are provided. The 302C-1 consists of indicator unit and coupler unit, the 302C-2 of coupler and unmounted meter and selector switch for custom installation.

180S-1 Antenna Tuner

This is an antenna matching device that can be configured as either an L or pi-network. Power 1-KW, Frequency range 3-30 Mc.

136C-1 Noise Blanker

This is an RF noise blanker for the 75A-4.

Return to the KWS-1 page
Return to the Virtual Collins Radio Museum

Copyright © 1996-WA3KEY & 1957-Collins Radio Company
This Home Page was created by wa3key, Thursday, February 22, 1996
Most recent revision Thursday, February 22, 1996