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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
G
A
B
C
D
1
GND
0
0
0
1
2
GND
1
0
0
1
3
GND
0
1
0
1
4
GND
1
1
0
1
5
GND
0
0
1
1
6
GND
1
0
1
1
7
GND
0
1
1
1
8
GND
1
1
1
1
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
Summary of Contents for DXE-RCA8C-SYS-4P
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