Download WLCM Nighttime Array at Holt, MI - Munn

WLCM Nighttime Array at Holt, MI
The Christian Broadcasting System of Fenton, MI, employed the firm of Munn-Reese,
Inc. for the design and tune up of is new nighttime facility at Holt, MI. The new 4 tower
directional array provided a large power increase from the previously allowed 70 watts
nighttime to the new 4.5 kW of nighttime coverage over Lansing, MI.
The new phasor was designed and built by Kintronic Labs and used the recently
developed technique of not returning the negative tower back to the power buss in the
phasor but instead dumping the returned energy into a dummy load. The power of the
transmitter was them increased to make up for the lost power dissipated in the load.
Keeping the negative tower off the phasor power buss flattened the match presented to
the transmitter and increased the over all bandwidth of the array. This bandwidth
increasing technique requires the use of dual Delta meters. One Delta Meter to measure
the power in the reject load and the other to monitor power from the transmitter. Both
currents are monitored by the remote control and power is adjusted accordingly.
The array was adjusted, field tuned and the proof of performance was completed by the
Munn-Reese, Inc. engineers mid November 2008. The FCC granted program test
Christmas Eve, December 24, 2008.
Exhibit 11.3
Horizontal Plat
of Antenna Array
Tower 1
North
Extent of Ground System
89.0° Electrical spacing
174.9 feet
(53.3 m)
184.0° True
Tower 2
180.0° Electrical spacing
353.8 feet
(107.8 m)
184.0° True
Transverse
Copper Straps
Tower 3
298° Electrical spacing
585.7 feet
(178.5 m)
186.0° True
Tower 4
The proposed ground system consists of 120 buried
copper radials, extending 53.9 meters in length, about
the base of the towers except where shortened to
terminate at property boundaries. The material used
for the radials will be #10 AWG, soft drawn copper wire
Exhibit 9.0
Nighttime Directional Radiation Pattern
0°
340°
350°
2000
10°
20°
30°
330°
40°
320°
1500
50°
310°
300°
60°
1000
70°
290°
500
280°
80°
270°
90°
0
260°
100°
250°
110°
240°
120°
130°
230°
140°
220°
150°
210°
200°
Measurements in mV/m
190°
180°
Call: WLCM
Freq: 1390 kHz
Hours: Night
Lat: 42-33-07 N
Power: 4.5 kW
Theo RMS: 740.41 mV/m @ 1km @ 4.5 kW
#
-1
2
3
4
Field
Ratio
----0.521
1.000
0.849
0.374
170°
160°
Measured Pattern: ▬▬▬▬
Standard Pattern: ▬▬▬▬
Meas. Pattern x 10: ▬ ▬ ▬
Stand. Pattern x10: ▬ ▬ ▬
HOLT, MI, US
Lng: 084-33-05 W
Phase Spacing Orient Height
Ref
TL
A
B
C
D
(deg)
(deg)
(deg)
(deg) Swtch Swtch (deg) (deg) (deg) (deg)
----------------- ----- ----- ----- ----- ----- -----145.1
0.0
0.0
93.0
0
0
0.0
0.0
0.0
0.0
0.0
89.0
184.0
93.0
0
0
0.0
0.0
0.0
0.0
142.8
180.0
184.0
93.0
0
0
0.0
0.0
0.0
0.0
-84.7
298.0
186.0
99.0
0
0
0.0
0.0
0.0
0.0
---------------------------------------MUNN–REESE, INC.
Engineering Consultants
Theoretical RMS: 740.41Broadcast
mV/m@1km
Erss = 1149.96 mV/m@1km
Coldwater, MI 49036 Q =
Standard RMS:
778.02 mV/m@1km
28.75 mV/m@1km