DSL line stealing when there is no tone - DANGER - Operational content

Greg Maxwell gmaxwell at martin.fl.us
Wed May 16 20:46:49 UTC 2001

On Wed, 16 May 2001, Steve Schaefer wrote:

> The main reason not to stick a tone on the DSL line is that the line
> coding (2B1Q) used by SDSL uses the baseband (low frequency part of the
> spectrum).
> For line codings that don't use the baseband (CAP, DMT and variants like
> G.lite), the DSLAM (telco central office DSL equipment) is always set up
> so that the DSL can be combined with a voice circuit over the same pair,
> so it still doesn't put a tone on the line.

I predict great profits for the first person to duct tape 100 'tracer
tone-generators' into a 23 inch rack with 48v DC power source. 

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message and may not reflect the policies of the Martin County Board of
County Commissioners.

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