ADS Antenna-Disconnect-Switch, Assembly And Operation Manual

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ADS
© 2018 – DL4ZAO – Status: Preliminary v010 Seite 2
Introduction
The ADS is a remote controlled switch, that completely disconnects the antenna from your radio and
grounds the antenna. It is designed to prevent transient overvoltage due to lightning and atmospheric
surge effects damaging your radio equipment. The Antenna Disconnect Switch is installed at the output
from your transceiver, power amplifier, or antenna tuner in line with the antenna’s coaxial feedline.
When the Power is turned OFF, the antenna’s coax signal wire and shield are shorted together and
grounded, and both the coax center and coax shield are disconnected from the radio. When the ADS
gets powered ON, it re-connects the antenna for normal operating. It and can handle 1.5 kW RF Peak
Power up to 50 MHz. With reduced power it is possible to use the ADS even at higher frequencies.
Important notice: For maximum protection a good earth ground connection is essential. See chapter
“ground earth connection” for details.
Functional diagram
Electrical characteristics

Supply/activation voltage DC 10-18 Volt

Operating current typ. 75 mA when activated/connected (at 12V Supply voltage)

RF-Connectors: female SO239/UHF coaxial socket

Antenna Socket fully isolated against case, RX/TX socket - braid connected to case

Supply connector: 2-pole screw terminal, twin core flexible lead

Case -aluminum diecast, dimension: 112 x 60 x 42 mm

Earth ground connection through a ground screw connected with the metal enclosure, or

Earth ground connection via the box flange-cover mounted on a metal plate connected to Earth

Transmission loss <0.05 dB up to 30 MHz, <0.12 dB up to 70 MHz, return-loss > 26dB

Max. Power: 1,5 KW PEP ( up to 30 MHz, 50% Duty Cycle, Load SWR <2)

Antenna through-connection is activated when Power applied

Remote controlled “OFF”, activated by manual or open collector switching

Connected/Activated condition is indicated by a green LED

Gas-Discharge Tube to provide supplementary surge protection during operation
relay-contacts shown in condition
“deactivated” (Supply Voltage „OFF“)