Lightning Strike Damage: TVs, Cable Modem & VCR

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
6 replies · 3K views
Messages
364
Reaction score
87
We had a thunderstorm Thursday evening and I think my house got zapped by lightening. I lost two TV's, a VCR, and my cable modem. Of course, the good news is that the cheaper the TV, the less damage it sustained. The best TV doesn't turn on at all, while the picture only fills half the screen and the colors screwed up on the other damaged TV. The cheap ones in the bedrooms didn't sustain any damage at all.

All the surge protectors for electrical power and not a one saw a glimpse of activity. The only thing in common is that anything connected to cable was at risk.

I've never heard of that happening before, although, if a lightning surge can travel through the phone line, then I guess the cable's not much different (I was also pretty sure the cable was buried, but maybe not).
 
Physics news on Phys.org
That's what it sounds like, a surge through your cable line. My TVs are all cheap, so I don't worry about them, but for the cable modem, I connect the cable line through a surge protector. I'm really not sure even that would help in the event of a lightning strike, but figure it at least protects against any spikes in power coming through when the power goes out and comes back on.
 
BobG said:
We had a thunderstorm Thursday evening and I think my house got zapped by lightening. I lost two TV's, a VCR, and my cable modem. Of course, the good news is that the cheaper the TV, the less damage it sustained. The best TV doesn't turn on at all, while the picture only fills half the screen and the colors screwed up on the other damaged TV. The cheap ones in the bedrooms didn't sustain any damage at all.

All the surge protectors for electrical power and not a one saw a glimpse of activity. The only thing in common is that anything connected to cable was at risk.

I've never heard of that happening before, although, if a lightning surge can travel through the phone line, then I guess the cable's not much different (I was also pretty sure the cable was buried, but maybe not).
Welcome to the club. Luckily you sustained less damage than I did, but it's still upsetting.

https://www.physicsforums.com/showthread.php?t=81078&highlight=lightning
 
I've been unplugging stuff during storms. Losing two TV's, a VCR, and a cable modem sucks though.
 
Physics_wiz said:
I've been unplugging stuff during storms. Losing two TV's, a VCR, and a cable modem sucks though.
Yeah, geez, you might have to start reading books for entertainment, or, gulp, talk to the other people in the house! :bugeye: :smile:

I don't think a lot of people really think about the cable line when thinking about unplugging things during storms.
 
BobG, in all likelihood your coax shield is not (properly) grounded. Cable companies rarely bother doing that. If it isn't, you should call them and have them ground it. And have them measure resistance to ground when they're done.
 
Last edited:
Moonbear said:
I'm really not sure even that would help in the event of a lightning strike, but figure it at least protects against any spikes in power coming through when the power goes out and comes back on.

Yes, the effectiveness of the home protection units is slight to none. In industry we use real surge protectiion that, in the case of a low power 110VAC line for example, sells for about $1200. The unit is designed to safely explode, which absorbs the energy from the strike.

The best course of action is to unplug everything when lightning is around.
 
Last edited: