Type 747CD Series GRANGER™ Horizontally Polarized Transportable HF Antennas 2-30 MHz or 4-30 MHz Frequency Range with Single Input Up to 20 kW Average 40 kW Peak Power Rating Horizontal Polarization Transportable Directional Log Periodic 2.0:1 Nominal, 2.5:1 Maximum VSWR (2.0 MHz Version) Short-, Medium-, and LongRange Communications General Description The Type 747CD high performance, log periodic antenna is lightweight, transportable, easy to erect and provides high gain and directivity with proven reliability. It is designed for short, medium and long range communications with a frequency range of 2 to 30 MHz or 4 to 30 MHz. One balun transformer is supplied for the 2 to 30 MHz range. A complete set of tools and winches, a special erection fixture and an instruction manual are also provided with the system. Adaptability For HF communications stations situated in hurricane and typhoon zones, the 747CD Series offers quick restoration of operational antenna circuits which are damaged by storms. When such damage occurs, the antenna can be erected and, with some advance preparation, made operational in less than two hours. The advance work includes selecting a tower site, burying the guy and catenary anchors in position and permanently installing the transmission line from the transmitter. The antennas are easy to erect. The 75ft (22.9m) tower which supports the antenna is supplied in nested sections with a special erection fixture that simplifies installation. Only two sets of guys are required. There are no locking latches, sliding sections or elaborate cable and pulley arrangements to malfunction; the design simplicity increases ease of assembly and reliability. Transportability All versions of the 747CD are sufficiently lightweight to be air transportable. They can also be moved from location to another by truck or other ground vehicle. Transportable weight and volume of each version are listed in the shipping information. supports each antenna, is fabricated of 6061-T6 aluminum alloy, a material extremely resistant to corrosion. The feedline and radiator assembly, prefabricated in a single unit, is of high strength Calsun-bronze wire. Spacers are of high-purity alumina ceramic. The tower has a rigid triangular truss configuration, with tubular vertical members that reduce frontal area and frictional wind drag. It is secured by two sets of Parafil rope guys attached to galvanized steel anchors 3.5ft (1.05m) long. The antenna elements are made of materials that resist the effects of corrosive agents such as salt spray, as well as ultraviolet light, arcing or corona. Strength and Durability The 747CD Series antennas are built to withstand harsh environments and repeated setup and takedown in the field. The single central tower, which 1 Organic plastics, which tend to carbonize under some of these conditions, are not used. Optional 4-30 MHz Compact Antenna This series is offered as an optional configuration when available ground area is limited. Except for operating frequency, weight and size, the performance characteristics and operating features are similar to the standard series. The frequency range can be extended from 4-30 MHz to 230 MHz through use of an optional field conversion kit. An additional type, 747CD-44, with power ratings of 20 kW average 40 kW peak is available to meet higher power requirements. Partial List of Users of 747CD Horizontally Polarized Transportable Antennas: U.S. Army, Air Force, Marine Corps and Navy; Australian Army and Air Force; U.K. Ministries of Defense and Aviation; NATO; and the Canadian and French Governments. Characteristics Frequency Range, MHz Polarization VSWR without Resistive Loading, max. Input Impedance, ohms Gain Azimuth Plane Half-Power Beamwidth, degrees 2-4 MHz 4-30 MHz Elevation Plane Pattern Max. Length of Any Part When Packed, ft (m) Wind Survival Rating, mph (km/h) Without Ice With 0.5 in (12mm) Radial Ice Erection Time (average ground Standard Series 2-30 Horizontal 2.0:1 (2.5:1 below 4.2 MHz) 50 See Page 3 Compact Series 4-30 Horizontal 2.0:1 50 See Page 3 Essentially omnidirectional 60 See Page 3 10 (3.0) 60 See Page 3 10 (3.0) 100 (160) 50 (80.5) 2 hours with a 5-man crew 100 (160) 50 (80.5) 2 hours with a 5-man crew 2 Antenna Dimensions Standard Series 2.0-30 MHz Compact Series 4.0-30 MHz Directive Gain vs. Frequency A ft (m) 317.5 (96.8) 303 (92.4) B ft (m) 328.3 (100.1) 186 (56.7) C ft (m) 120 (36.6) 120 (36.6) D ft (m) 75 (22.9) 75 (22.9) Elevation Plane Coverage 3 Elevation Plane Radiation Patterns (Directive Gain in dB Relative to Isotropic) Ordering Information Type Number Frequency Range MHz 747CD-2 747CD-3 747CD-7 747CD-9 747CD-11 747CD-42 747CD-43 747CD-44 747CD-47 747CD-49 2-30 2-30 2-30 2-30 2-30 4-30 4-30 4-30 4-30 4-30 Bulletin 1410B 05/08 Data subject to change without notice. Power Rating kW Average Receive Only 1 10 2.5 20 Receive Only 1 20 10 2.5 Peak Input Connector Female Receive Only 2 30 30 40 Receive Only 2 40 30 30 Type N 7/8” EIA 1-5/8” EIA 7/8” EIA 1-5/8” EIA Type N Type N 1-5/8” EIA 1-5/8” EIA 7/8” EIA 4 ASC Signal Corporation • 606 Beech Street West • Whitby, Ontario, Canada • L1N 5S2 • t. +1 (905) 668 3348 • f. +1 (905) 668 8590 • www.ascsignal.com