Ultra-small high-speed coaxial cable with dual filament insulator

An ultra-small, high-speed 75 ohm coaxial cable comprising:

• a. a longitudinal conductor having a diameter of 0.0063″ to 0.0508″;
• b. a support wrap helically wound about the conductor according to a wrap pitch and comprising first and second insulator filaments helically twisted together according to a twist pitch, wherein the filaments each have a diameter of 0.003″ to 0.025″ and a tolerance of ±0.0025″;
• c. an insulator sheath at least partially covering the support wrap and the conductor, wherein:
• the insulator sheath has an inner diameter of 0.030″ to 0.200″ and an inner diameter tolerance of ±0.0005″;
• the insulator sheath has a wall thickness, and a wall thickness tolerance of ±0.00025″;
• and the insulator sheath is supported by the support wrap at a particular number of support locations and is thereby offset from the conductor to form an airspace between the conductor and the insulator sheath;
• d. a concentric ground shield disposed about an outer periphery of the insulator sheath;
• and
• e. a concentric outer insulator jacket disposed about an outer periphery of the concentric ground shield, wherein:
• f. the cable has a characteristic impedance tolerance of ±3 ohm.

An ultra-small, high-speed cable comprising:

• a. a longitudinal conductor;
• b. a support wrap helically wound about the conductor according to a wrap pitch and comprising first and second insulator filaments helically twisted together according to a twist pitch, wherein the filaments each have a diameter of 0.0025″ to 0.010″ and a tolerance of ±0.00025″;
• c. an insulator sheath at least partially covering the support wrap and the conductor, wherein:
• the insulator sheath has an inner diameter of 0.020″ to 0.075″ and an inner diameter tolerance of ±0.0005″;
• the insulator sheath has a wall thickness, and a wall thickness tolerance of ±0.00025″;
• and the insulator sheath is supported by the support wrap at a particular number of support locations and is thereby offset from the conductor to form an airspace between the conductor and the insulator sheath;
• d. a concentric ground shield disposed about an outer periphery of the insulator sheath;
• and
• e. a concentric outer insulator jacket disposed about an outer periphery of the concentric ground shield.

A method of manufacturing a high-speed, ultra-small coaxial cable with a characteristic impedance of 50±1 ohms, said method comprising the steps of:

• a. preparing a support wrap by helically twisting together first and second insulator filaments according to a twist pitch, wherein the filaments each have a diameter of 0.0025″ to 0.010″ and a tolerance of ±0.00025″;
• b. helically winding the support wrap around a longitudinal conductor according to a wrap pitch, wherein the conductor has a diameter of 0.008″ to 0.0253″;
• c. at least partially covering the support wrap and the conductor with an insulator sheath, wherein:
• the insulator sheath has an inner diameter of 0.020″ to 0.075″ and an inner diameter tolerance of ±0.0005″;
• the insulator sheath has a wall thickness, and a wall thickness tolerance of ±0.00025″;
• and the insulator sheath is supported by the support wrap at a particular number of support locations and is thereby offset from the conductor to form an airspace between the conductor and the insulator sheath;
• d. disposing a concentric ground shield about an outer periphery of the insulator sheath;
• and
• e. disposing a concentric outer insulator jacket about an outer periphery of the concentric ground shield.