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Bussani
11-07-2011, 01:06 PM
This may be a silly question, but when running your phone/net cables through a surge protector, does it matter exactly which order it all goes in? That is, should the surge protector go between the wall and the modem-router, or between the modem-router and the PC(s)? I'd assume before would be better to give the modem-router a little protection, as well as to protect anything plugged into it.

Chilling_Silence
11-07-2011, 02:03 PM
Yeah I put my DSL Modem and Wireless access point on a UPS, but not the PC's.

Surge Protectors you might as well pop on them. I don't usually bother with putting the phone line through a protector though, just the power.

tweak'e
11-07-2011, 07:18 PM
your actually far more likely to get "spiked" via phone lines than through the power. so phone line surge protectors is more important.
protector should go between modem and phone line.

the big problem is actually getting decent phone line protectors. most are just a simple gas discharge tube. better ones are muilti staged and fused so a big spike blows the fuse and kills the phone connection.

Bussani
12-07-2011, 11:16 AM
Thanks for the replies. I'll go ahead putting it between the wall and the modem then.

Chilling_Silence
12-07-2011, 11:53 AM
the big problem is actually getting decent phone line protectors. most are just a simple gas discharge tube. better ones are muilti staged and fused so a big spike blows the fuse and kills the phone connection.

Do they have much of an effect on the line sync speed? Coz all the ones I've used have been of mediocre quality and reduced speeds too much to make them viable long-term...

Terry Porritt
12-07-2011, 12:05 PM
They will all have an insertion loss. My home brewed device consisting of a double gaseous arrestor across the phone lines and centred to earth, two 6.8 ohm resistors and 2 1.5Kw superfast Transorb diodes, adds 1db to the downstream line attenuation, and reduces downstream rate a bit.

But it is the price to pay for a degree of protection against lightning strikes on the phone lines.

Chilling_Silence
12-07-2011, 12:40 PM
Yeah so if it's only adding that much attenuation, I'd take a stab in the dark that if you *were* syncing at say 12m/bit, you might at *worst* lose 1m/bit?

I've used two in the past, and they would pretty much halve the sync speed ... Hence why I ditched them.

I'd be interested to learn a bit more about this though, do you happen to know of any info / guides on DIY that are available online? When it comes to electrical things I'm pretty much a baby on the matter :-/

Terry Porritt
12-07-2011, 01:03 PM
Yeah so if it's only adding that much attenuation, I'd take a stab in the dark that if you *were* syncing at say 12m/bit, you might at *worst* lose 1m/bit?

I've used two in the past, and they would pretty much halve the sync speed ... Hence why I ditched them.

I'd be interested to learn a bit more about this though, do you happen to know of any info / guides on DIY that are available online? When it comes to electrical things I'm pretty much a baby on the matter :-/

Pretty well spot on :), just made a few tests, the synched downstream rate fell from 14094kbps to 12998kps with a 2 db increase in attenuation this time.

Speedtests showed a corresponding drop
http://speedtest.net/result/1381474943.png

http://speedtest.net/result/1381477949.png


I have only just dug out this unit again with current crop of thunderstorms going around. I played around with different devices some years ago while on dialup, after we had a frying tonight strike on our lines.

You never know whether they work or not, that is the problem.

Also I'm not sure whether protectors that were made for dial up would be also ok for ADSL. I seem to remember they had bigger insertion losses.

Terry Porritt
12-07-2011, 02:06 PM
I don't have the reference sites for surge protectors now, except for this one:
http://ec2.epanorama.net/documents/telecom/telesurge.html

Some of the circuits seem too complicated.......bearing in mind lightning takes the shortest path...:) so simplest seems best to me. :banana

The gaseous arrestor was the last DSE had. I don't know if they can still be obtained. The old telephone master jacks used to have them. The Transorbs were from Radiospares and of the bidirectional type.
http://en.wikipedia.org/wiki/Transient_voltage_suppression_diode

John H
12-07-2011, 03:07 PM
(snip)The Transorbs were from Radiospares and of the bidirectional type.(snip)

You know we love it when you talk dirty Terry.