3 ms·
How interesting! How do old-fashioned wired telephones and cable TV deal with this problem?
by michaelt 3y ago
How interesting! How do old-fashioned wired telephones and cable TV deal with this problem?
- fleventynine 3y agoThe cable TV shield is grounded where it enters the house. The POTS lines aren't grounded (they're differential, like 1000base-T), but the telephone company installs some sort of protection device in the exterior box that allows sparks to jump across to the local ground if the voltage differential gets too high.