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BevFlex-4X Installation Manual Rev 2.23  November 2019 

 

Quad shield is ideal, but not necessary.  The better the shielding, the less likely you will pick up unwanted 
interference.   We recommend using a good quality cable with a UV resistant jacket and weatherproof connectors.  
Any good quality 75 Ohm characteristic impedance coaxial cable can be used, including coaxial cables that 
incorporate a supporting, steel messenger/carrier wire.    
 
If long spans are required between supporting posts or trees, the use of coax with a supporting messenger/carrier 
wire is desirable.   Much of the surplus coaxial cable from CATV companies has an integrated messenger wire and 
can often be obtained for free.   If the cable has a supporting messenger wire, this wire needs to be insulated from 
the end supports and all intermediate supporting structures.  Normally the messenger wire can be left floating from 
the RG-6 shield, but can be optionally connected to the shield of the F connectors on the end termination units with a 
3/8” ID lug and nut. 
 
Flooded, self-sealing RG-6 is an advantage for BOG configurations and buried feed lines back to the shelf. Small 
animals may chew through the outer jacket. Flooded RG-6 will seal the openings, preventing water from getting into 
the coax. 
 
14.   

What effect does my local ground conductivity have on antenna performance, and should I make any 

adjustments to the height above ground to compensate for this?

 

 

When mounted at least 7 ft. above ground level, electromagnetic modeling of the BevFlex-4X antenna shows little 
effect on the an

tenna’s performance over a range of soil conductivities  between  0.1 mS/m and 50 mS/m, which are 

typically found in most locations. 
 
15.   

How will weather conditions affect the performance of my antenna?

 

No more so than with any other wire antenna installation.  The reversible Beverage allows you to switch directions to 
reduce interference from atmospheric storms coming from predominantly one direction.  In such cases, it is better 
than other antennas for receiving under high noise conditions. 

16.   

Why are there ground connections on each of the end terminating units?

 

The ground rods provide a connection between the custom reflection transformers at each end of the antenna and 
the ground under the antenna, which completes the circuit between the two ends of the antenna. 

17. 

 

Will I need to use an external preamp with this antenna? 

Generally, no external pre-amplifier is required or desired as signal levels from the BevFlex-4X are well above the 
noise floor of your receiver on frequencies below 10 MHz.   Received signals from the BevFlex-4X will almost always 
be LOWER in “S” meter readings than on your transmit antenna, but the overall signal to noise ratio will be higher.  
An antenna pre-amplifier may be helpful for a BevFlex-4X configured as a Beverage-On-Ground (BOG) or EWE at 
frequencies above 7.0 MHz. 

18.   

What kind of connector is required to interface with my radio?

 

The output from the switching and termination unit is via a standard “F” connector matched to the 50 Ohm input 
impedance found on most receivers.  You will need to provide a 50 Ohm cable and the adapters required to connect 
to your particular radio.  (“F” to BNC, PL-259, RCA phono, etc.) 

19.   

Do I need to use 50 ohm cable between the switching unit and my radio?

 

With the short lengths of cable involved in most installations, either 50 Ohm or 75 Ohm coaxial cable can be used.  

Содержание BevFlex-4X

Страница 1: ...na systems now in use worldwide for weak signal low noise reception This product retains ALL of the features of the original BevPro BevFlex series while adding the flexibility to accommodate a total o...

Страница 2: ...End Terminator Units 1 Antenna Feed Unit 1 BevFlex 4X Switch Unit 1 BevFlex 4X Quick Start Guide 1 Getting Started The BevFlex 4X is a versatile system that can be used to build five types of low ban...

Страница 3: ...tends to each end point of the antenna The outer shield of the coaxial cable is continuously connected regardless of where the unique feed system is placed along the entire length of the antenna The t...

Страница 4: ...0m 30m 20m 15m 160m 80m 40m 30m 20m 15m 100 ft P F G G E E Nil P G E E E 150 ft F F G E E E Nil F G E E G 250 ft G G E E E E F G E E E G 350 ft E E E E G G G E E E G F 450 ft E E E E F F G E E E F P 5...

Страница 5: ...stems BevFlex 4X Beverage antenna kit will enable you to construct a Beverage receiving antenna that has a uni directional receiving pattern that can be reversed In either of its two directional patte...

Страница 6: ...ou As a reminder this is a RECEIVE ONLY ANTENNA AND MUST NEVER BE CONNECTED DIRECTLY TO THE OUTPUT OF A TRANSCEIVER The application of more than a few milliwatts of power into the system will result i...

Страница 7: ...f RG 6 cable can be obtained at local builder s supply stores or over the Internet Use of 50 ohm coax is not recommended for either the Beverage antenna element or the feed lines back to the shack The...

Страница 8: ...ures Several different types of electric fence insulators are readily available for this purpose A height of 7 to 10 feet above ground is ideal and keeps the wire high enough to allow mowing under the...

Страница 9: ...Unit provides both common mode RF and DC Ohmic isolation of the feedlines from the antenna It is recommended that the shields of the two feedlines be connected to the station ground at the entrance to...

Страница 10: ...ver DO NOT CONNECT THE BevFlex 4X TO ANY TERMINAL CAPABLE OF TRANSMITTING AS YOU MAY DAMAGE THE BevFlex 4X ANTENNA COMPONENTS If your receiver or transceiver does not have a separate receiver antenna...

Страница 11: ...u accidently blow this fuse the unit will be non operational If this occurs you can replace this fuse with an identical 50 ma fuse available from Unified Microsystems Bell P N MRF 50 available from Di...

Страница 12: ...about using an external switching arrangement to create a receive antenna function external to the transceiver Many of these external T R relays do not have enough isolation and fast enough switching...

Страница 13: ...cy references on 3 330 kHz and 7 850 kHz WWV time and frequency reference on 2 500 5 000 and 10 000kHzThese are all reliable and predictable HF sources that can aid in understanding the performance of...

Страница 14: ...physical length of the antenna This extended electrical length characteristic along with the ability to hide the antenna in sod can put the advantages of this low noise receiving antenna within reach...

Страница 15: ...0 ft to 300 ft on ground or buried 1 2 deep FWDIN REV IN Feed unit may be placed at any point between terminators REV END FWD END Direction refers to direction of main receive lobe Terminal 2 to GND T...

Страница 16: ...st be installed at each end of the EWE The Terminator Unit internal jumpers must be configured for EWE use The factory setting is for Beverage type antennas See Table 3 and Figure 19 and Figure 20 for...

Страница 17: ...OUT REV IN RX Forward Reverse BevFlex 4X Block Diagram EWE Configuration RG 6 feed lines to shack Any length do not need to be the same length Directions 12 Antenna Wire 30 ft to 40 ft typical length...

Страница 18: ...G but is really a phased array of two short vertical antennas that are top coupled by the horizontal wires It may also be thought of as a pair of back to back EWE antennas mounted above ground Details...

Страница 19: ...cting the appropriate taps on the BevFlex 4X universal termination units the Flag now is reversible with individual RG 6 coax feed lines connected via the termination unit to each of the two vertical...

Страница 20: ...are suspended about 18 above ground level More information about the VE3DO antenna is available at the following link http audiosystemsgroup com VE3DO pdf The Terminal Unit internal jumpers must be c...

Страница 21: ...ized for 160M Horizontal length 20 40 40 optimized for 160M 20 optimized for 80M Terminator Unit 10 Terminators placed near Feed Unit Ground Rod REV END FWD END Note Feed line connections are reversed...

Страница 22: ...and to a single ground rod Antenna Wire connection to Other Terminator Stud 2 1 2 2 3 Terminator Internal Jumper Settings The five antenna types supported with the BevFlex 4X have different impedance...

Страница 23: ...te unused ports but they might be 50 or 75 ohms You will need to verify that the switch you use provides the proper 75 Ohm termination and if necessary make modifications 9 Troubleshooting the BevFlex...

Страница 24: ...the Forward position the resistance reading from the center pin of the B port to shield should be approximately 1 Ohm This is the resistance of the transformer winding With the direction switch in th...

Страница 25: ...s higher signal levels than EWE or VE3DO antennas Flag antennas can be constructed to be rotatable Inverted EWE An unbalanced short above ground antenna with simple support requirements VE3DO A balanc...

Страница 26: ...should position the Beverage antenna cable 7 to 10 feet above ground is ideal in that it maintains the correct impedance as well as allowing for mowing under the antenna and minimum interaction with w...

Страница 27: ...l conductivities between 0 1 mS m and 50 mS m which are typically found in most locations 15 How will weather conditions affect the performance of my antenna No more so than with any other wire antenn...

Страница 28: ...ith WD 40 or contact cleaner to maintain a good connection and prevent corrosion Use Vaseline or silicon grease on the threads of the F connectors when you put them together All wires and coax cable f...

Страница 29: ...s This spacing and orientation will minimize the coupling and interaction between the two antennas 28 Can I feed more than one receiver from my BevFlex 4X antenna system Yes you can use any standard 5...

Страница 30: ...on The only way to accurately measure the rest of the components of the system is to use an RF antenna analyzer to determine the actual RF impedances of the parts of the system you are troubleshooting...

Страница 31: ...Is there a simple way to check the Front to Back Ratio F B of my BevFlex 4X Yes a good way to check the front to back ratio of the antenna is to find an AM broadcast band radio station that is more t...

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