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installation, there are some fundamental concepts that you should know. 
 

1.

 

Have you sized your array to achieve the desired performance within your space? Do you 
know where you will be locating your Receive Eight Circle Array? Review the explanation 
of the optimal monoband and multi-band frequency coverage of the Eight Circle Array in 
sections entitled 

Array Performance

Site Selection 

and

 Sizing the Array

 

2.

 

Are you ready to build your system? Proceed! 

 
The 

DXE-R8C-SYS-V3 Receive Eight Circle Array Packages 

includes: 

 

DXE-RCA8C-1

  Receive Eight Circle Array Controller 

 

DXE-CC-8A

 Special eight position Receive Eight Circle Control Console

 

modified to 

p12 Vdc for powering the active antennas.

 

  

 

DXE-SSVC-2P

 Stainless Steel V-Clamp for mounting the 

RCA8C-1

 Receive Eight Circle 

Array Controller to a mounting post between 1" and 2" OD 

 

Eight 

DXE-RSEAV-1 Active Verticals 

with AVA-3 Active Matching Units, Aluminum 

Vertical Elements, Insulated Mounting System and Stainless Steel V-Clamps to be used 
with customer supplied ground rods for ground mounting

 

 

DXE-RG6UFQ-1000 

(Two) 1000 Foot Rolls, Quad Shield Coaxial Cable, 75Ω, RG6 

Flooded Cable 

 

DXE-CPT-659

 Coaxial Cable Prep Tool for RG6, 75Ω Coaxial Cable, w/extra blade 

 

DXE-SNS-CT1

 F-Connector Compression Tool for 75Ω coaxial cable connectors 

 

DXE-EX6XL-25

 Package of 25 F Connectors for quad shield 75Ω RG6 coaxial cable

 

 
Additional Parts Required, Not Supplied with the DXE-R8C-SYS-V3 

 

 

One additional DXE-RG6UFQ-1000 

75Ω quad shield Coaxial Cable that may be required 

for the main feedline from the station to the array

 

 

 

Five-Conductor Power and Control Cable.

 

The modified 

DXE-CC-8A

 Control Console 

interfaces to the 

DXE-RCA8C-1 

Eight Circle Array Controller through a 5-wire cable to 

select one of eight directions and to power the eight active elements. Economically priced 

DXE-CW9S

 is a 9-conductor control wire which may be used allowing the user to use the 

spare wires to double up on power and return lines for current carrying capability.

 

 

Eight Ground Rods 

6 ft. length x 5/8 in. diameter min., used as supports and crucial 

grounding for the eight DXE-RSEAV-1 Receive Short Element Active Verticals.

 

 

Eight Circle Layout 

 
The optimized array for single band performance has vertical elements 
arranged in a circle with a 

radius

 of about 175 feet for 160 meters, or 84 

feet for 80 meters, or 44 feet for 40 meters. A two-band array for 80 and 
160 meters should also have a radius of about 84 feet. See the 

Theory of 

Operation 

sections for exact dimensions, options for wider frequency 

coverage and guidance in choosing the best orientation. 
 
The default direction of the array with no voltage (BCD 000) places 
elements 1 and 6 in front and elements 2 and 5 at the rear, with pairs of 

Summary of Contents for DXE-R8C-SYS-V3

Page 1: ...em Package DXE R8C SYS V3 U S Patent No 7 423 588 DXE R8C SV3 INS Revision 0 DX Engineering 2022 1200 Southeast Ave Tallmadge OH 44278 USA Phone 800 777 0703 Tech Support and International 330 572 320...

Page 2: ...11 Vertical Element Feedlines 12 Typical DXE R8C SYS V3 Receive Eight Circle Configuration 13 Delay Line 14 Optimizing the Array 14 Theory of Operation of the Receive Eight Circle Array 15 System Des...

Page 3: ...ands typically 160 80 and 40 meters it is functional from 500 kHz to 30 MHz Excellent directivity in a smaller space than phased Beverages for better signal to noise ratio than transmit arrays and oth...

Page 4: ...75 coaxial cable connectors DXE EX6XL 25 Package of 25 F Connectors for quad shield 75 RG6 coaxial cable Additional Parts Required Not Supplied with the DXE R8C SYS V3 One additional DXE RG6UFQ 1000...

Page 5: ...ight Circle Array Controller eight DXE RSEAV 1 Receive Short Element Active Vertical Antennas and one Delay Cable with F Connectors installed These units interconnect and work together using factory d...

Page 6: ...ler unit should be mounted as shown in Figure 3 with cover upward and the control and coaxial cable connections downward to prevent water from entering the box The stainless steel base of the Receive...

Page 7: ...connections are labeled G A B C D The terminals use the same connection letters and are connected G to G A to A B to B C to C and D to D On the RCA8C 1 the green connector is a two part connector as s...

Page 8: ...ontrol Line Lengths Minimum Copper Wire Gage AWG Length 24 1 000 feet 22 1 500 feet 20 2 000 feet Active antenna circuitry needs a good voltage supply to operate properly When supplying power to an ac...

Page 9: ...proximity to transmitting antennas 1 10 wavelength of the lowest transmitting frequency This is possible provided the active units are powered off at least 5 ms before transmitting An optional sequenc...

Page 10: ...a change in signal or noise level you need to improve the ground A second rod spaced a few feet away from the first one may correct the problem or 10 to 12 ground radials each 15 ft long should provi...

Page 11: ...nt Feedline and Delay Line It is important to use 75 feedline to the operating position from the DXE RCA8C 1 unit Do not use amplifiers combiners filters or splitters that are not optimized for 75 sys...

Page 12: ...ge them Excessive tightening torque can loosen the chassis mounting nut allowing the connector body to rotate and fracture the mounting tabs on either installation or removal of the connector F connec...

Page 13: ...gure 7 Coaxial Cables are shown in various colors for clarity Shown with optional DXE RPA 2 Receive Pre Amplifier DXE RFCC 1 Receive Feedline Current Choke and optional DXE CW9S Control Cable Power co...

Page 14: ...a and set the receiver to the narrowest selectivity you expect to use Receiver noise power is directly proportional to receiver bandwidth going from 2 5 kHz selectivity to 250 Hz selectivity reduces n...

Page 15: ...an stable pattern with high directivity over wide bandwidth W8JI initially developed and used this array in the 1980 s This array started appearing in the 1990 s at larger more advanced low band DX st...

Page 16: ...dband active elements this array has unbeatable performance across a single band The Eight Circle Array upper frequency limit for a clean unidirectional pattern is slightly above where the array is 35...

Page 17: ...rimary benefit Antenna gain is a secondary advantage As frequency increases the fixed array size becomes electrically larger in terms of wavelength The increased electrical spacing produces higher sen...

Page 18: ...nductors regardless of element design for a given style of element The effect on pattern depends almost entirely on how much surrounding objects absorb and re radiate signals if the undesired structur...

Page 19: ...power lines as possible Proximity to Transmitting Antennas Eight DXE RSEAV 1 Receive Antenna Active Vertical active elements and your transmitting antenna need only minimal physical separation to main...

Page 20: ...d with a radius of 327 wavelength This pattern achieves the best Receiving Directivity Factor RDF which is a figure that compares the forward lobe gain to the average gain of the antenna array in all...

Page 21: ...lowable side lobe levels as represented closely to the pattern 35 wavelength radius shown in Figure 9 For example an array built to cover 160 80 and 40 meters has a highest frequency of 7 3 MHz and a...

Page 22: ...atterns in Figure 10 were generated using EZNEC and show the effects on the patterns when varying the radius of the array These patterns are not to be viewed as pointing in a default or particular dir...

Page 23: ...not know the VF of the coaxial cable you are using you must directly measure the electrical length of the coaxial cable you have with an analyzer or obtain cable with a known VF Table 3 shows delay l...

Page 24: ...imensions rather than operating frequency which allows for the use of a single delay line for optimum directivity over a very wide frequency range This results in phase being correct for a rearward nu...

Page 25: ...Array is sized by multiplying the free space wavelength at 1 832 MHz of 537 feet wavelength times the optimum pattern circle radius of 0 327 wavelength which yields an optimal circle radius of 175 6...

Page 26: ...2 26 66 13 172 8 345 6 319 3 0 604 3 500 70 29 35 14 91 8 183 7 169 7 0 604 3 650 67 40 33 70 88 1 176 1 162 7 0 604 3 800 80M only or 160 80M 64 74 32 37 84 58 169 2 156 3 0 604 7 200 40M only 34 17...

Page 27: ...pulled inward C Shorted Open conductors due to water Check feedlines and control cable D Zapped by lightning pulse or RF overload Make sure units are at least 1 2 wavelength on the lowest frequency a...

Page 28: ...Active antennas and any transmit antennas If that distance is less and high power is used then the Time Variable Sequence Unit TVSU 1B must be used to interrupt power to the AVA units 2 Damaged Receiv...

Page 29: ...tem relay unit with the control cable connected and again at the end of the control cable that is disconnected from the Receive Eight Circle System relay unit If measured voltages are not between 10 t...

Page 30: ...ing the RF If one or more Active Receive Verticals produce a low or no signal then the AVA unit at the base of that antenna may not be receiving power Retest for DC power at the antenna end of that fe...

Page 31: ...31 NOTES...

Page 32: ...allation damaged from severe weather including floods or abnormal environmental conditions such as prolonged exposure to corrosives or power surges or by the performance of repairs or alterations outs...

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