RL478-50ALU
4-7/8" Unflanged Rigid Line (Aluminium outer conuctor)

Rev : 03 | Rev date : 11 Aug 2022

RFS manufactures a range of unflanged and flanged rigid coaxial transmission lines and accessories to meet all commonly used EIA/IEC standards from 1-5/8" to 8-3/16".
4-7/8" unflanged rigid line is a 50-ohm rigid coaxial transmission line, and is ideal for indoor connections between RF broadcasting equipment.

FEATURES / BENEFITS

Inner conductor is of the highest purity copper (99.95%) for minimum attenuation and lowest operating temperature.
Outer conductor is made from lightweight aluminium, easy to cut and install
Materials are milled to exact dimensions to ensure strict compliance with specifications and stable characteristic impedance.
Elbow spigots and couplings are of silver-plated brass for high conductivity.

4 7/8" Unflanged Rigid Line

Technical features

Structure
Product Line		Rigid Line
Product Type		Unflanged rigid line (Aluminium outer conductor)
Size		4-7/8"
Feeder Type		Rigid coaxial transmission line (unflanged)
Outer Conductor Material		6060-T8 Aluminium
Outer Conductor OD	mm (in)	123.2 (4.85)
Outer Conductor ID	mm (in)	120 (4.724)
Inner Conductor Material		C102000 Copper, 99.95% pure
Inner Conductor OD	mm (in)	52.1 (2.051)
Inner Conductor ID	mm (in)	50.1 (1.972)

Electrical Specifications
Maximum Frequency	MHz	862
Impedance	Ω	50 +/- 0.5
Relative Propagation Velocity	%	99.8
Peak Power Rating	kW	2160
RF Peak Voltage	kV	14.7

Mechanical Specifications
Weight	kg/m (lb/ft)	3.7 (2.48)
Finish		Natural
Recommended clamp spacing	m (ft)	2 (6.5)

Ordering Information
Standard Lengths	mm (ft)	2750, 5500 (9, 18) [Note 3]

Environmental Specifications
Ambient Temperature Range	°C(°F)	-40 to + 60 (-40 to 140)
Humidity		95%, non condensing

Attenuation and Power Rating
Frequency, MHz	Attenuation, dB/ 100m	Attenuation, dB/ 100ft	Average Power kW (Note 1)	Average Power kW (Note 2)
50	0.14	0.044	153	205
88	0.19	0.059	115	154
98	0.20	0.062	109	146
108	0.21	0.065	104	139
150	0.25	0.077	88	118
174	0.27	0.082	82	110
202	0.29	0.089	76	102
240	0.32	0.097	70	93
300	0.36	0.108	62	84
400	0.41	0.125	54	72
470	0.44	0.135	50	67
500	0.46	0.140	48	65
520	0.47	0.143	47	63
600	0.50	0.153	44	59
665	0.53	0.161	42	56
719	0.55	0.168	40	54
800	0.58	0.177	38	51
820	0.59	0.179	38	51
862	0.60	0.183	37	49


Attenuation at 20°C (68°F) Mean power rating at 40°C (104°F) ambient temperature Note 1. Outer temp rise 24°C (75°F), Inner temp rise 65°C (149°F) Note 2. Outer temp rise 30°C (86°F), Inner temp rise 85°C (185°F) Note 3. Custom lengths are available on request

Elbows
Elbow Model No		RL478-50ALU-EL	RL478-50ALU-ELT
Elbow Type		Non-tuneable	Tuneable
VSWR 0-862 MHz		1.025:1	1.014:1
Elbow Weight	kg (lb)	5.3 (11.7)	5.6 (12.3)

Accessories
Accessory Model No		RL478-50ALU-STR	RL478-50AL-FLA	RL478-50-IJK	RL478-50-SHR	AD49U-N
Accessory Description		Straight Coupling - Inner & Outer	Flange Adaptor - Clamp Type	IEC Inner Joining Kit	Suspension Hanger	4-7/8"u/f - Type N Adaptor
Accessory Weight	kg (lb)	0.54 (1.19)	0.7 (1.54)	1.3 (2.9)	1.3 (2.9)	2 (4.4)