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LL (Low Loss) Coaxial Cables

Unique cable design: The braid configuration and the expanded PTFE dielectrics of the LL cable constructions contribute to lower attenuation levels at higher frequencies, while providing shielding effectiveness levels that exceed those of flexible MIL-C-17 cables. Flat strips of silver plated copper are braided over the dielectric core with an intermediate metallized polyester or polyimide layer, and an outer round wire braid.
Improved electrical characteristics: LL cables with expanded PTFE dielectrics exhibit low coefficients of expansion over the entire operating temperature range from -100° C to +250° C. Impedance discontinuities are minimized at the cable- to-connector interface. Higher levels of power can be transmitted because higher temperatures do not affect the cable due to the temperature stability of the tape. Where phase versus temperature requirements are critical, LL cables allow for an approximately 75% lower phase shift and change in propagation time delay due to temperature. Temperature cycling tests have been performed on a number of cables with positive results.
Lowest attenuation for any given size: LL coaxial cables, with expanded PTFE dielectrics and strip braid composite configurations, offer attenuation from 20 to 35% below other mil spec cables of comparable size. When size and weight are considerations, LL cables should be considered. The graph below defines maximum attenuation levels for all LL cables referenced on the next page.
Technical support available: We continually work with cable assembly houses and connector manufacturers to ensure maximum system reliability. Cable designs take into consideration size and weight constraints, existing connector availability and termination techniques. Sources of supply for connectors operative to 18 GHz may be recommended.
Many special constructions available: The chart on the following page outlines just a few designs we have manufactured. Some of the more popular constructions are standard stock items, and many additional cables are available for prototype assemblies. Additional cables not referenced here are available to meet specific customer requirements.

Product #: LL335i


Conductor Solid Silver Plated Copper
Outer Diameter Conductor 0.089 ± 0.001 in
Dielectric PTFE Tape
Outer Diameter Dielectric 0.250 ± 0.005 in
Inner Braid Flat Silver Plated Copper
90% min. coverage
Outer Diameter Inner Braid 0.255 ± 0.005 in
Inner Shield Aluminum Polyster
Outer Diameter Inner Shield 0.261 ± 0.005 in
Outer Braid Round Silver Plated Copper
90% min. coverage
Outer Diameter Outer Braid 0.277 ± 0.005 in
Jacket Green Tint FEP
Outer Diameter Jacket 0.300 ± 0.005 in
Marker Tape Harbour Industries LL335i
Nom. Weight per 1000 ft. 76.0 lb
Min. Bend Radius 1.5 in
Min. Continous Length 50 ft
Put-up 18" wood, (1) length per spool
Operating Temprature Rating -55 to 200 ºC
RoHS Compliance Complies with RoHS (Directive 2002/95/EC)

Electrical Characteristics

Impedance 50 ohms ± 2
Nom. Capacitance 24.5 pF/ft
Nom. Velocity of Propagation 83.0 %
VSWR (Max 400 MHz to 18 GHz) 1.35:1
Typical Attenuation @ 100 ft. 11.3 dB @ 5.00 GHz
17.1 dB @ 10.00 GHz
22.4 dB @ 18.00 GHz
3.1 dB @ 0.40 GHz
4.9 dB @ 1.00 GHz
8.5 dB @ 3.00 GHz
Max. Attenuation @ 100 ft. 12.5 dB @ 5.00 GHz
19.0 dB @ 10.00 GHz
26.0 dB @ 18.00 GHz
3.5 dB @ 0.40 GHz
5.5 dB @ 1.00 GHz
9.5 dB @ 3.00 GHz

Test Method

Test Points 801
IF Band Width 35 kHz
Sweep Time 6 s
Test Length 6 ft
Connector Type Male SMA Plug
Sampling Plan Per Mil-STD-105
k1 0.149
k2 0.0001674