OT: DSL/Modems

[Bill Vermillion]

On or about Mon, Oct 25 11:35 , while attempting a Zarathustra 
emulation GCC Consulting thus spake: 

>  

> > -----Original Message-----
> > From: 
> > filepro-list-bounces+gcc=optonline.net at lists.celestial.com 
> > [mailto:filepro-list-bounces+gcc=optonline.net at lists.celestial
> .com] On Behalf Of Fairlight
> > Sent: Sunday, October 24, 2004 10:48 PM
> > To: filePro List
> > Subject: Re: OT: DSL/Modems

> > You'll never BELIEVE what Bill Vermillion said here...:

> > > And an interesting thing that can happen with DSL - since
> > > it is a high-frequency signal - similar to RF - is that
> > > sometimes you can lose your voice line - as there needs
> > > to be enough conductivity to carry the voltages for ring,
> > > etc., - that the HF will seem to bleed past LF impairments
> > > and the DSL will work when the regular phone line wont.

> > That's exactly what happened when I lost my voice line to 
> > that hum.  -If- I could get a dialtone at all, I had the hum 
> > at about 25db+.  If I hung up, it wouldn't--it would just be 
> > the hum, no dial tone.  To force a dialtone, I actually had 
> > to use multiple devices off-hook at once to force it to 
> > acknowledge and kick over a dialtone.  Ahh, the fun effects 
> > of a hard ground.  Words cannot convey my joy.  :)  However, 
> > it was a blessing disguised as a curse, since after the week 
> > of hell, I actually ended up with a 30%+ increase in average 
> > DSL performance.  I'll take that, even if a week of hell is the cost. 
> > Yet the DSL chugged merrily away at 97KB/sec while the voice 
> > line was completely knackered before they tried the first 
> > fix, 120KB/sec after the first fix, and after they finally 
> > actually cleared the voice line, 137KB/sec, and since then 
> > it's improved into the 143-153 range, depending on my sync, 
> > which will go weeks at a time without being touched.  It's 
> > -so- much less finnicky now than it used to be.
> > 
> > But yeah, I've had the DSL working full bore and a next to 
> > unusable (in some instances that week, unusable) voice line.  
> > BTDTGTTS.

> The problem my client has is most likely "noise" on the phone
> line portion of this shared line.

With DSL it can be a capacitance that is 'shorting' the HF
carriers.  Noise you can hear is usally more of a problem for
the LF devices - eg things you can hear.  Noise you can't hear -
interference from radio/tv/etc - will affect the high end.

> Since their DSL service is from Covad, I don't want Verizon
> messing with this line. DSL is fine.

> The easiest thing was to move this modem to a shared dial-up
> phone line. They are connecting to A 9600 BAUD connection for
> both dial-up connections they have to make. The interesting
> thing is the transmissions are actually going faster over the
> dial-up rather the shared DSL/phone line. Now it is possible
> that this line has been somewhat noisy for the last few years
> and has just gotten worse.

> As I said originally, this combination worked for over a year
> without a problem. Only since early Sept. did they start to
> have a real problem.

And since you have a time frame where this occured some nosing
around might give you the answer.

Has ANYTHING been added in the building.  Is it a building
with more than one client - and if so check the wiring closet.
Has there been a new cell-phone tower put up nearby?

Are they in an area like we had here - with storm after storm
after storm dumping huge amounts of water - and thus causing water
penetration into the transmission lines.

If the dial-ups are going faster than the DSL and you don't want
to contact COVAD/Verizon with the problem, it would seem logical
to drop the DSL.

-- 
Bill Vermillion - bv @ wjv . com