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RAS-4 Receive Antenna Switch

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Receive only antennas are critical for success on the low bands. Unfortunately they only receive in one or two directions, and most are far too large to rotate. The RAS-4 allows switching of up to four antennas using RG6 coax, the standard for these types of antennas.

The RAS-4 is housed in a NEMA rated enclosure with a gasketed lid. A cable gland seals the control cable entry. Finally the internal circuit board has a conformal coating for additional protection.

Common mode noise pick up can ruin the performance of receive antenna systems. The RAS-4 isolates both the center conductor and shield of unselected ports. A bifilar ferrite choke further reduces common mode currents.

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By default, unselected ports are terminated for 75 ohms. The user
can change to 50 ohm, open circuit, or center conductor-shield short
by soldering wire jumpers.


The RAS-4 can be mounted with the enclosure flanges or with the
included L bracket for mounting to a pole or post.


The RAS-4 is a receive only antenna switch. Do not transmit into it.

A controller switch is not included. It will work with many commercial
12V switches or a simple home brewed one. See the User Manual
for more information.

Click to Enlarge RAS-4 Specifications

Antenna Selection:  4:1
Dimensions:  Approx. 4.5” X 3.5” X 3.25” (11.4 cm X 8.9 cm X 8.3 cm), not including the bracket. 
Connector type: F (5)
Unselected port termination: 75Ω default, 50Ω, open, shorted. Wire jumper selectable
VSWR: < 1.5:1 from 100kHz to 20MHz
Insertion loss: < 0.4dB from 100kHz to 20MHz
Port to Port Isolation: > 45dB from 100kHz to 20 MHz
Control Cable: 4 wire, Not included
Switch Controller: 12V, Not included
PDF - RAS-4 User Manual

Order your RAS-4 Receive Only Antenna Switch here:

QTY Price Description
 $124.95    RAS-4 Receive Only Antenna Switch 
  US Shipping is $8.00 per order
  Canada Shipping is $11.00 per order  International Shipping is $36.00 per order
  Important Information on International Orders

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