Badcaps.net Forum
Go Back   Badcaps Forums > General Topics > Network Design & Troubleshooting
Register FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 07-01-2010, 06:11 AM   #1
japlytic
Badcaps Veteran
 
japlytic's Avatar
 
Join Date: Oct 2005
City & State: Rockhampton, Queensland, Australia
My Country: Australia
Line Voltage: 240VAC 50Hz
I'm a: Hobbyist
Posts: 1,521
Default Why DSL filters go bad over time

In an old ADSL filter which was not adequately filtering out noise on the phone line at a client's house was a 1uF 100V Jun Fu bipolar electrolytic capacitor.

I recommend against using aluminium electrolytic capacitors in DSL filters, because they can deteriorate over time, even the good ones. But you can't tell if they have electrolytic capacitors unless you open them (and void the approval).
Good filters have polyester or polypropylene and sometimes tantalum (still a good choice) capacitors inside.

The largest non-electrolytic capacitor I have seen in a DSL filter was a 1uF 63V polyester unit.
__________________
My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.
japlytic is offline   Reply With Quote
Old 07-01-2010, 06:54 AM   #2
Scenic
o.O
 
Scenic's Avatar
 
Join Date: Sep 2007
City & State: Duisburg
My Country: Germany
Line Voltage: 230VAC 50Hz
Posts: 2,615
Default Re: Why DSL filters go bad over time

Jun Fu? no wonder..
they always dry out.. even from just sitting around unused..
__________________
The USA have Barack Obama, Bob Hope, Stevie Wonder and Jonny Cash.
We have Angela Merkel, no hope, no wonder, no cash.
Scenic is offline   Reply With Quote
Old 07-01-2010, 08:52 AM   #3
Junk Parts
Court Jester
 
Junk Parts's Avatar
 
Join Date: Jun 2006
City & State: Baltimore-A Rat Hole With A Harbor
My Country: USA
Line Voltage: 120VAC@60Hz
I'm a: Knowledge Seeker
Posts: 8,104
Send a message via AIM to Junk Parts
Default Re: Why DSL filters go bad over time

I have a brand new ADSL filter on my phone that does almost nothing to block the DSL noise. Going to have to get under the desk and change it out.
__________________
“It ain't what you don't know that gets you into
trouble. It's what you know for sure that just ain't so.”
Mark Twain
"I wish to have no connection with any ship that does not sail fast; for I intend to go in harm's way."

John Paul Jones
Junk Parts is offline   Reply With Quote
Old 07-01-2010, 09:06 AM   #4
stj
Badcaps Veteran
 
Join Date: Dec 2009
City & State: Europe
Posts: 4,757
Default Re: Why DSL filters go bad over time

tantalum is polarised, and "very" sensitive to reverse current.
it would be insanely stupid to use one inplace of a bi-polar device unless your trying to start a fire.
stj is offline   Reply With Quote
Old 07-19-2010, 11:18 PM   #5
Uranium-235
Radioactive
 
Uranium-235's Avatar
 
Join Date: Aug 2007
City & State: tehas
My Country: US
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 2,392
Default Re: Why DSL filters go bad over time

or you could just go with cable. for an extra $10-15 a month you dont' have to deal with this crap. of course its not available everywhere I know.

but if you have cable available in your area, please use it, thank you.
Uranium-235 is offline   Reply With Quote
Old 07-20-2010, 12:34 AM   #6
ratdude747
Black Sheep
 
ratdude747's Avatar
 
Join Date: Nov 2008
City & State: New Albany, IN
My Country: USA
Line Voltage: 120VAC 60Hz
I'm a: Student Tech
Posts: 13,280
Send a message via Yahoo to ratdude747 Send a message via Skype™ to ratdude747
Default Re: Why DSL filters go bad over time

cable is not a solid connection... it peaks... but, it is worth it if is not too pricey

i have always heard you should change the filters yearly as they do go bad... i used to have it in my old house, but we have cable here at the new house (no dsl here as the phone lines are too old).
__________________


(Insert signature here)
ratdude747 is offline   Reply With Quote
Old 07-20-2010, 10:38 PM   #7
severach
Badcaps Veteran
 
Join Date: Aug 2007
City & State: Michigan
My Country: USA
Line Voltage: 120VAC 60Hz
I'm a: Hobbyist Tech
Posts: 983
Default Re: Why DSL filters go bad over time

The caps in my filter look like polyester.
severach is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 06:13 AM.


Badcaps.net Technical Forums © 2003 - 2014
Powered by vBulletin ®
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

Did you find this forum helpful?