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I have lost a dialup modem due to a 2

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pilihp

Technical User
Dec 18, 2002
118
GB
I have lost a dialup modem due to a lightning strike on the overhead phone line. Is there a product that will provide protection? I always disconnect the phone line from the modem and the ac power when computer is not in use but have been caught out by the sudden and unexpected strikes that regularily occur in Italy.
 
Hi

You need to get yourself a surge protector. I've got one that is a multi adapter extension with sockets in the end for the phone line.

Hope this helps

[lightsaber] May The Force Be With You [trooper] [yoda]
 
TSSTechie, thanks for that, The phrase 'surge supressor'is the operative thing. 'Lightning strikes' etc did not bring up much in Google.
 
Modem Protection.
Having researched this subject it seems the only available devices to be found need to be connected to the ac mains supply and also they only work 'ONCE'. What can I do to protect the modem used with a laptop running on batteries only? It is impracticle to use a device that only survives one strike as there can be multiple strikes per day!
 
MOVs degrade with each activation. And how much they degrade is dependent on how much of a surge they damp out.
The commercial power strips that are MOV protected are suggested for replacement in 1 to 3 years.
If you take a hit that degrades one totally you probably have lost the laptop at the same time.
The reason for the AC connection is for the ground connection. Open one of the power strips up and you will see that there are 3 MOVs inside, 1 across the mains, and 1 between the mains and the ground. I suspect that the same holds true for the phone connection.
Since the phone line is tied to ground at the demarcation point, I suspect that you could rig a duplicate there using the phone company installed ground.

Ed Fair
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.
 
You also get what you pay for. IMO the very cheap surge suppressors are basically worthless.

Go with a company with a reputation for surge surpression, APC and Tripplite are two well know ones.

Many companies also make surge suppression equipment just for notebooks. Here is an example from APC's website.
 
Edfair: Many thanks; The critical word MOV has enabled me to read up all about protection devices and I found a very useful article which gives the circuit of a simple to build device which puports to be very effective and is exactly what I'm looking for. Here is an address which could help others:
 
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