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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 System unit.
Use a steady, non-fading ground wave signal from a low or
medium power daytime AM Broadcast station that is over 10 miles away, on a frequency high
in the band, or another constant signal source near 160 or 80 meters, well away from the array,
to test that each Active Vertical receives the same signal level. Do not use sky wave or night
signals for these signal level tests.
