General information

The ads is a remote-controlled disconnect switch that protects sensitive radio systems from overvoltages on the Antenna. It is inserted into the feed line between the antenna and the receiving/transmitting System. In the inactive state, without supply voltage, in the ads the connection between the antenna socket and the socket to the radio system is separated by relay Contacts. At the same time, the inner conductor of the coaxial cable is briefly closed by the antenna with the grounded metal housing. When switched on (activated) the line is switched from the antenna to the radio System. Then another 600V arresters (GDT) protects against surge Pulses. The ads is designed for transmitting services of 1KW in all frequency bands up to 75 mhz. It can also be used at higher frequencies with reduced power and Reception. Important note! For effective protection, The metal housing of the ads must be connected to a good aerial earth. The basic requirements for grounding will be addressed later in the sections "installation" and "execution of grounders".

function diagram

The schematic shows the relay contacts in the inactive state (operating voltage "off")

Properties

Supply voltage DC 10-18 Volt
Current consumption 75 MA (with 12v supply Voltage) in activated state
RF Connectors: Socket SO239/UHF
Antenna socket is insulated, RX/TX socket is connected to the housing Earth
Supply connection cable: via screw terminal-two wires red/black
Housing: Aluminium die-cast housing, Housing Dimensions 112 x 60 x 42 mm
Connection via screw connection (m6) to the housing or
Earth connection by screwing the flange cover onto a grounded metal plate
Insertion loss<0.05 db="" bis="" 30=""></0.05><0.12 dB bis 70 MHz db="" bis="" 70=""></0.12 dB bis 70 MHz>
Through power: 1.5 kw (up to 30 mhz, 50% duty cycle, SWR<2)></2)>
Activation: by applying the DC supply voltage
Arresters for surge protection in switched-on operation
Activation display by a green LED
Remote controlled off: via manual switch or open collector switch

Functioning and operation

In the off (disabled) state, the connection is separated from the inner conductor and from the external conductor/screen of the coaxial cable to the radio system via relay Contacts. The inner conductor of the coax feed line from the antenna is short-circuited via relay contacts with the grounded metal housing. If the supply terminal K3 is connected to a DC voltage between 10 and 18V, in the ads the connecting cable is switched from the antenna to the KOAXBUCHSE from the radio System. In the activated operating state, a arresters with a ignition voltage of 600V ensures the protection against Overvoltages. A green LED indicates when the ads is Activated. Activated-the connection from the antenna to the radio system is switched off (led green lights up)-the line from the radio system is Disconnected. The supply line to the antenna is connected to the metal Housing/earth (led off). The different methods of activation can be found in the "activation variants" Section. Note:

In the transmission mode: on uncoordinated antennas with high VSWR, the standing waves on the feed line generate voltage maxima and if the ads are inserted at a point of the voltage maximum, it may occur that there is the breakthrough voltage of the Gasableiters of nominal 600V is exceeded in the ADS. This danger exists only with high SWR and transmission services via 1kW.

Remote Power supply: When operating preamplifiers that are remote-fed via the coaxial cable or active antennas, It should be noted that the ads antenna disconnect switch in the disabled state briefly closes the inner conductor of the coaxial cable from the antenna to Ground. A remote feed switch (bias-t) is therefore on the rx/tx side in front of the antenna disconnect

Power supply

A supply voltage of 10 V to 18V is required to operate the Relays. The supply voltage is connected to the circuit board via a screw terminal (k3). A piece of Red-black twin strand is used as the supply line. The nominal current consumption in the activated state is Type. 70 MA at 12 V supply voltage Type. 85 Ma with a supply of 13, 8v. The supply voltage for activating the ads can be either from the transceiver or from the The radio system or from a DC power supply.

For radio systems with a 12v supply output for auxiliary devices, This can be used to activate the ads the output must be able to supply the required current from 90mA. When the radio or receiver is switched on, the ads are activated at the same time and the antenna is switched On. Many devices have an RCA/RCA jack installed as a supply Output. Usually the positive pole is on the inside Pin. When connecting a plug to the Red-black supply line, pay attention to the correct polarity: red = plus, Black = minus/gnd.

If a supply output for auxiliary devices is missing from the radio system, the ads can be powered from a 12v DC power supply when switching the DC voltage, the ads are activated and the antennas are switched On. When connecting the Red-black supply line from the screw clamp K3 Please pay attention to the correct polarity: red = plus, Black = Minus/gnd

Remote "off"/Fernabschaltung

The ads has a remote control connector on a post bar (k4). If the ads are permanently connected to a supply voltage and activated, it can be disabled by short-circuiting the two pins of K4 of the ads via a FET Switch. The short-circuit connection can either be done via an external manual switch with potential-free contacts or actively controlled via an open collector transistor switch (active-low). The maximum switching voltage on the switch corresponds to the supply voltage, the internal resistance is 47kΩ. When connecting an open collector switch, pay attention to the correct Polarity. With the help of this remote shutdown, the activation/deactivation of the ads via the cat interface of a TRX and an automatic tape decoder (E.G. Stationmaster o Etc.).

Installation

The ads antenna disconnect is looped into the coaxial cable between the radio system and the ANTENNA. In the case of radio transmitters, the ads should be inserted after the PA and the antenna tuner. The ads can be used in buildings, in the shack, on the cable to the antenna or directly at the ANTENNA. It offers the best protection, however, when it is inserted outside the building into the cable way before the antenna cable enters the building. In an outdoor installation, weather-protected housing in a suitable box is Advisable. Important: for effective protection against atmospheric surges, it is necessary to connect to a good aerial earth. The earth connection point of the ads antenna circuit breaker is to be connected to the ground or the main grounding rail (pas) in the shortest possible distance. The requirements for a standard-compliant grounding of antennas are described in en 60728-11 (vde 0855-1) and din vde 0855-300. As the terrestrial connection point, the ads antenna disconnect is equipped with a M6 screw on the Housing. The earth connection should be connected to the aerial grounding in a short distance. To connect the ads to a Potentialausgleichsscjoeme, a pipe with a cross section of Min 6mm2 copper is Recommended. If the connection is to be of Lightning current, 16 mm2 copper would be required. The external conductors of the aerial cables, metal pipes of the water or heating system or the protective conductors of the domestic power grid are not suitable as grounding conductors.

Execution of Grounders

According to the applicable standards, Earthers are to be built at a depth of 0.5 m and at a distance of 1 m from the Foundation. The connection between the Earther and the main grounding rail pas-should be flash current Viable. The same is true for the aerial cable. A single solid wire with a cross-section of min. 16 mm2 copper, 25 mm2 aluminium or 50 mm2 steel is considered to be capable of lightning Current.

Circuit diagram

Measurement diagram through damping

Scaling: horizontal 10MHz/tick mark, vertical 0, 1dB/tick mark

Activation variants

Supply and activation together with the supply voltage of the radio System. When the power supply is switched on, the ads are Activated. The ads is deactivated when the power is switched off, the switching to the antenna is Disconnected.

"remote off". Supply and activation together with the supply voltage of the radio System. When the operating voltage is switched on, the ads are Activated. The ads can be deactivated by closing the remote switch contacts "remote off" despite the supply voltage.

For radio systems with a 12v supply output for auxiliary devices, This can be used to activate the ADS. When the radio or receiver is switched on, the ads are activated and switched on at the same time.

Disclaimer

The ads antenna disconnect is a component for supplementary protection of sensitive transmission/Empfangsanlagen against static charges and atmospheric surges from the ANTENNA. The ads antenna circuit breaker is not a substitute for lightning protection measures or other safety devices as laid down in the relevant standards for antenna systems and radio Systems. The operator is solely responsible for the compliance with the regulations in the construction of a radio transmitters/receiving system and the antenna System. Any liability for damage to persons or property in this context is Excluded.

Standards and standards

[1] din vde 0855-300 (vde 0855-300): 2008-08 Radio transmitters-/-Empfangssysteme for transmitter output power up to 1 kw – part 300: Safety Requirements. [2] din en 60728-11 (vde 0855-1): 2005-10 cable networks and antennas for television signals, sound signals and interactive services – part 11: safety Requirements. [3] en 62305-3 (vde 0185-305-3) Lightning Protection – protection of construction equipment and Persons. Copyright Notice © Sept. 2017, Günter Fred mandel, All rights reserved

Bom

POS.	Number	Part No.	Value	Description
1	1	C1	100nF, Ceramics	Value Print: 104
2	1	C2	10nF, Ceramics	Value Print: 103
3	2	d1, D2	1N4007
4	1	D3	LED
5	4	k1, k2, k5, K6	Solder Pin
6	1	K3	Screw Terminal 2-pole	Pitch 5mm
7	1	K4	2-pol pin header with Plug and cable
8	1	R1	47K
9	1	R2	2, 7K
10	1	R3	2, 7K
11	2	RLY1, RLY2	Relay 12v
12	1	T1	BS170
13	1	X1	arresters, GDT Bourns 2049-600
14
15	1	RF Double Jack	SO239 through Bush
16	1	RF Double Jack	SO239 through Bush with bulkhead fitting

17	1	Implementation Grommet	5mm
18	1	Rca/rca socket	For insulated mounting
19	1m	Twin Strand	Red/black
20		Mechanikkleinteile	Screws and nuts
21		Insulating Parts
22	1	PCB Printed circuit board
23	1	Housing Aluminium with flanged cover	Hammond 1590BSFL

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Ads-antenna Disconnect Switch

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