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Features Overview
The Top Ten Devices Op Swapper (OS) is an accessory that allows a single antenna system to be
shared between two transceivers, while providing protection to the non-transmitting radio’s front
end. Here are some of its features:
Positive Lockout
The OS uses electrically interlocked relay contacts that prevent two transmitters
from being active at the same time.
Ultra High Isolation
Typical isolation to the non-transmitting radio vs frequency:
Frequency (MHz)
Isolation (dB)
1.8 to 7
100
14
95
21
85
28
80
Transceiver Inhibit
The non-transmitting radio is held in an inhibited state to prevent inadvertent
transmitting into an open circuit. The inherent circuitry works directly with Yaesu and Elecraft
K3/K3S (we will call them a K3 in this manual) radios. This functionality can be implemented for
any radio pair by use of external relays.
High Power Rating
Rated at 200 Watts, allowing use with virtually all currently available
transceivers.
Switched Outputs
Two 12Vdc, 1A switched outputs provide an easy way to control external
circuitry such as LEDs or control relays.
LED Indicators
Two LEDs are provided on the front panel to indicate which radio is transmitting.
Simplified Connection Diagram
Fig. 1 – Simplified Connection Diagram
In this manual, we refer to the two radios as “A” and “B,” as shown above.
