How to choose good quality video cable for residantial industry
Check the PVC Jacket, inside copper wire brading can be seen from the surface: pressing net of "roughness" shows good processing technology and good quality cable;otherwise, smooth appearancewhich does not show the pressing net "roughness" by, is a poor quality cable.
2. check the shielding of copper wire braiding: if the roots of copper wire are enough and pure, check solderability, tin plated copper wire scraping look inside is not copper wire, but aluminum with white colour, alloy wire hardness is significantly greater than the copper wire netting; sparse, uneven distribution, and the insulating layer wrapped tight is cable.
3. check the core: ---SYV cable diameter is 0.78 to 0.8mm, SYWV cable for 1.0mm; the recent emergence of a SYV75-5 core diameter is 1.0mm cable, the characteristic impedance of the cable, certainly not 75 ohm, 75 ohm is applied to the transmission system.
4. check the core wire and the insulating layer adhesion: oblique incision and insulating layer, according to the direction of peeling pull wire, see the core wire and insulating layer without bonding process materials; cable has great cohesion, poor bonding without cable.
test: take one meter cable, delamination core line, insulation, shielding, outer sheath, each 1cm long.The method is: two hands hold the adjacent two layers of the cable, pulling in the opposite direction; good cable general force pull, poor cable can not easily pull out.