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2)   When rotating the modified DXE-CC-8A Control Console switch from position 1, 2, 3 and 4, if all 

LEDs light normally, measure BCD output voltages. Nominally, +12. Connections A, B, C and D, 
reference to the ground pin G as shown below. The selected position will supply the BCD logic voltage 
as shown in the chart below.   

 

Switch Position 

GND 

GND 

GND 

GND 

GND 

GND 

GND 

GND 

Table 1 - Modified CC-8A Output Truth Table

 

 “1” 12 Vdc (Default) 

 

3)   If the voltages are not normal, less than +10 to 18 Vdc, with the control line connected, then disconnect 

the control line and retest the modified DXE-CC-8A Control Console. If voltages that were not correct, 
are now okay, that indicates a short in the control line or a problem in or beyond the

 

Receive Eight 

Circle System relay unit. 

 

 

4)   If the modified DXE-CC-8A has only a couple LEDs lit with the control cable disconnected, then it 

may have sustained lightning pulse damage and will need to be repaired or replaced.  A new modified 
DXE-CC-8A is available from DX Engineering.  

 

Continue troubleshooting the array control

 with a good modified DXE-CC-8A or by using a 1A fused 

power source.  

 

 

5)   Determine if the control line is intact by resistance or voltage testing each conductor for shorts with the 

far end of the control cable disconnected from the Receive Eight Circle System unit. 

 

6)   With a good modified DXE-CC-8A

 

or other power source connected, measure A, B, C and D control 

conductor voltages at the Receive Eight Circle System 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 b10 to 18 Vdc on the selected line, a resistive, short or open 
circuit problem exists in the control line or in the Receive Eight Circle System relay unit or antenna 
feedlines. Normal voltages on the connected control line will cause relays to switch inside the Receive 
Eight Circle System unit. If switching voltages are correct, lack of system directivity or gaps in 
reception may be due to antenna, feedline or delay line issues. 

 

7)   Test the Active Antennas by feeding a voltage on the tested control line A and/or B conductor(s) to 

select one direction of Receive Eight Circle System unit operation. Simultaneously feed normal 
operating voltage on the tested conductor that powers the Active Verticals for reception. If a low value 
fuse blows, then a short circuit may be isolated by disconnecting antennas and reconnecting them one at 
a time.  

 

If no fuses have blown and connected voltages stay near the n12 Vdc levels, then: 

 

8)   Test for active operating voltage at the end of each antenna feedline. If all are good, proceed. If not, 

repair feedlines and/or connectors. If voltage is present on the power line to the Receive Eight Circle 
System relay unit, but is not measured at the end of good feedlines, inspect inside Receive Eight Circle 
System relay unit to determine if there is an obvious reason that Active Vertical Antenna power is not 
making it out the antenna ports. A bad connection outside of the 

RFS

 relay unit is usually the problem, 

and rarely has a component failure inside the

 

Receive Eight Circle System relay unit been discovered.  

 

Proper Receive Eight Circle System phasing

 

requires that each Active Vertical Antenna, and its 

respective equal length feedline, actually provides the same signal level to the Receive Eight Circle 

Содержание DXE-RCA8CB-SYS-4P

Страница 1: ...E RCA8CB SYS 4P U S Patent No 7 423 588 DXE RCA8C SYS 4P INS Revision 0b DX Engineering 2018 1200 Southeast Ave Tallmadge OH 44278 USA Phone 800 777 0703 Tech Support and International 330 572 3200 Fa...

Страница 2: ...10 Vertical Element Feedlines 11 Typical DXE RCA8C SYS 4P Receive Eight Circle Configuration 12 Delay Line 13 Optimizing the Array 13 Theory of Operation of the Receive Eight Circle Array 14 System D...

Страница 3: ...tter signal to noise ratio Reduced susceptibility to high angle signals compared to phased Beverage antennas as well as superior performance over EWE Flag Pennant K9AY antennas Switching console selec...

Страница 4: ...mpression Tool for 75 coaxial cable connectors DXE SNS6 25 Package of 25 Snap N Seal Connectors for 75 F6 coaxial cable Additional Parts Required Not Supplied with the DXE RCA8C SYS 4P One additional...

Страница 5: ...troller eight DXE AVA2 Active Matching Units for your vertical elements and one Delay Cable with F Connectors installed These units interconnect and work together using factory default settings to con...

Страница 6: ...ontroller 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 Re...

Страница 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...

Страница 8: ...ol 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 active...

Страница 9: ...mitting 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 sequencer such as the DXE...

Страница 10: ...s than 5 8 OD A good ground system improves the array performance and enhances lightning survivability It is important that the ground system is identical for each active antenna in the array You can...

Страница 11: ...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 systems All element feedlines must be 75 and can...

Страница 12: ...the chassis mounting nut allowing the connector body to rotate and fracture the mounting tabs on either installation or removal of the connector F connectors require modest torque typically 6 12 inch...

Страница 13: ...Figure 8 Coaxial Cables are shown in various colors for clarity Shown with optional DXE RPA Receive Pre Amplifier DXE RFCC Receive Feedline Current Choke and optional DXE CW9S Control Cable Power con...

Страница 14: ...na 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...

Страница 15: ...s a clean 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 ban...

Страница 16: ...broadband 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 i...

Страница 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...

Страница 18: ...uctors 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 structure...

Страница 19: ...mity to Transmitting Antennas The AVA2 Active Matching Units with customer supplied vertical elements or the DXE ARAV4 8P Receive Antenna Active Vertical with Relay active elements and your transmitti...

Страница 20: ...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 directions inclu...

Страница 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...

Страница 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...

Страница 23: ...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 line length calculations based on the dimen...

Страница 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...

Страница 25: ...e 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...

Страница 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...

Страница 27: ...e 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...

Страница 28: ...Active antennas and any transmit antennas If that distance is less and high power is used then the Time Variable Sequence Unit TVSU must be used to interrupt power to the AVA2 units 2 Damaged Receive...

Страница 29: ...s disconnected from the Receive Eight Circle System relay unit If measured voltages are not between 10 to 18 Vdc on the selected line a resistive short or open circuit problem exists in the control li...

Страница 30: ...of that antenna may not be receiving power Retest for DC power at the antenna end of that feedline If 10 to 18 Vdc is found then the Active unit may need to be serviced or replaced New AVA2 units are...

Страница 31: ...31 NOTES...

Страница 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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