- Noise margin vs. speed
- Posted by Richard Tobin on December 7th, 2005
I recently upgraded my ADSL conneciton from 500kb to 2Mb. From what
I'd read here, I expected the noise margin to be reduced by about
12dB, but in fact it's barely changed (from 31.0dB to 29.5dB). I see
that the output power has increased from 16.5dBm to 19.0dBm - does
this explain it?
-- Richard
- Posted by Kraftee on December 7th, 2005
Richard Tobin wrote:
Doubt it, I would personally wonder about the accuracy of the readings
your router is giving you...
- Posted by Phil Thompson on December 8th, 2005
On 7 Dec 2005 21:02:58 GMT, richard@cogsci.ed.ac.uk (Richard Tobin)
wrote:
31 was probably a maximum displayable value (binary), the actual might
have been 39 dB - lose 12 from that then add on 2.5 for the extra
power and bingo, 29.5 dB.
Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali
AOL - the unlimited ISP of choice for heavy downloaders.
- Posted by George on December 9th, 2005
It could be that your ISP had your line provisioned at 2Mb anyway, and
was just limiting it to 512 from their end - There are a few ISPs who do
that (including AOL). Obviously, there would be no change in noise
margin etc if this has been the case.
- Posted by Richard Tobin on December 9th, 2005
In article <v2tfp1hkm5bgu66m4kasiv7slv6anv1mfp@4ax.com>,
Phil Thompson <phil.thompson@spamcop.net> wrote:
Possible, but given that it can do .5dB I would have expected the maximum
to be 31.5dB...
-- Richard
