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Here are a few other causes for malfunction:
1) Damaged Dual Vertical Array Relay unit due to lightning. This has been reported only a
couple of times and is not very likely.
2) Dual Vertical Array Relay units that were damaged by animals or insects.
If necessary, the following further troubleshooting procedure may assist in finding the malfunction.
Advanced Troubleshooting Procedure
1) Test the
DXE-EC-DVA
Dual Vertical Array (DVA) Control Console unit, which should be connected
only to the control lines of the Dual Vertical Relay Unit. When the DVA Control Console is connected
to the control cable, do all three of the selected switch position LEDs light normally when rotating the
directional control knob?
2) When rotating DVA Control Console switch from position 1, Broadside and 2, if all three LEDs light
normally, measure BCD output voltages. Nom12 Vdc. Connections A and B, 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
1
2
1
GND
H
0
BROADSIDE
GND
0
0
2
GND
0
H
Output Truth Table -
“H” 12 Vdc
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 DVA 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
Phasing Relay Unit.
4) If the DVA Control Console has only a one or two LEDs lighting up with the control cable
disconnected, then it may have sustained lightning pulse damage and will need to be repaired or
replaced. A new DVA Control Console (
DXE-EC-DVA
) is available from DX Engineering.
Continue troubleshooting the array control
with a good DVA Control Console 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 DVA Phasing Relay Unit.
6) With a good DVA Control Console
or other power source connected, measure 1 and 2 control
conductor voltages at the Phasing Relay Unit with the control cable connected, and again at the end of
the control cable that is disconnected from the Phasing 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 Phasing Relay Unit. Normal voltages on the connected control line will cause
relays to switch inside the Phasing Relay Unit. If switching voltages are correct, lack of system
directivity may be due to antenna feedline(s) or the vertical elements.
7) Test reception of each Vertical Antenna by connecting each antenna feedline, one at a time, to an
activated port on the Phasing Relay Unit. This assumes that a good port has been identified and is
functioning properly. Normal reception must be confirmed from each antenna. If one or both monoband
verticals produce a low or no signal, then vertical elements, connections or feedlines may need to be
serviced or replaced.
8) If both vertical elements tested provide the same signal level in one port, then change switching to
select the other port and try each antenna on that port one at a time, testing for the same level of
reception. If one or two of the antenna ports are dead or has diminished reception, there may be a
problem in the Phasing Relay Unit.
