VTF8.5 and VTF11.2 are triax cables, physically similar to the standard type (they use the same series connectors), but have detail differences to improve flexibility. The centre conductor is stranded, rather than solid, and the lower cross-sectional area of copper in VTF11.2 produces a slightly higher signal attenuation than VTS.
They are available with a choice of jacket materials, to suit users different requirements:
VTF manufactured by Bedea uses TPE (thermo-plastic elastomer), a synthetic “rubber “with a long pedigree in industrial cable applications, and with extremely high flexibility. This is our most flexible Triax cable.
Two types are available from Draka. Draka “Triflex-PVC” is a PVC compound that has a higher abrasion resistance than TPE, although is not quite as flexible. Draka “Triflex-PUR” has a flexible polyurethane jacket, for the very highest level of abrasion resistance.
A termination service is available for these cables, and the appropriate Canford, Fischer and Lemo connectors are stocked. Readymade cables using both standard and flexible Triax are available – see Canford Triax Camera Cables.
Technical Specification:
| Inner conductor: |
19/0.30mm silver plated copper (1.34mm²) (VTF11.2) |
|
7/0.35mm silver plated copper (0.67mm²) (VTF8.5) |
| Dielectric: |
Cellular polyethylene, 6.0mm diameter (VTF11.2), 4.5mm diameter (VTF 8.5) |
| Outer conductor: |
94% optical coverage, 24 x 7 x 0.14mm silver plated copper |
| Intersheath: |
8.5mm diam. (VTF 11.2), 6.5mm diameter (VTF 8.5) |
| Screen: |
24 x 8 x 0.14mm bare copper |
| Jacket: |
VTF8.5 – OD 8.4mm - 8.5mm, red |
|
VTF11.2 – OD 11.0 - 11.2mm, red |
|
Material as specified in text |
| Impedance: |
75 ohms ±3% |
| Capacitance (nom): |
54pF/m (centre conductor to 1st screen) |
| Attenuation at 1MHz: |
0.55dB/100m (VTF 11.2), 0.80dB/100m (VTF 8.5) |
| Attenuation at 10MHz: |
1.80dB/100m (VTF 11.2), 2.60dB/100m (VTF 8.5) |
| Attenuation at 100MHz: |
6.70dB/100m (VTF 11.2), 8.80dB/100m (VTF 8.5) |
| Velocity ratio: |
0.8 (200MHz) |
| Max. voltage (peak): |
3.5kV RF |
| Minimum bending radius: |
80mm (VTF 11.2), 60mm (VTF 8.5) |
| Maximum pulling strength: |
350N (VTF11.2), 250N (VTF8.5) |
| Operating temperature: |
-35°C to +80°C |
| Weight: |
16kg/100m (VTF 11.2), 10.5kg/100m (VTF 8.5) |
| Reel length: |
500m |
| Cut lengths: |
Available in any multiple of 1 metre (stock types only) |