Line split is causing a decrease in line speed

giggity

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Hiya,

Here is the situation: We have a small office connected to our house, kind of like a small cottage. Our line that comes in to our main house is split in parallel to the office.

When the office is connected, the speeds are as follows:
Screenshot (6).png

When the office is not connected, these are the speeds:
Screenshot (7).png

The effects I can see from this:
  • Attainable rate increases by ~1.5mbps.
  • The delay is reduced by almost half (though it's [SUB]tiny[/SUB]).
  • There is actually output power.
  • Upstream SNR increases, as does downstream (presumably, since attainable rate increases).
  • Attenuation remains constant.

Anyone know what might be happening here?
My best guess would be that the additional resistance of the wire is causing the strength of the electric current to decrease.

Thanks
 
You are most likely seeing electromagnetic effects such as reflection and radiating on the office leg.

Try to place a microfilter/splitter at this junction to prevent ADSL spectrum going to the office.
 
POTS-ISDN-ADSL-Splitter.jpg
 
But how do you connect two pieces of copper to that? I have POTS filters on every device.
Why two?

You should have a jack in the house and a jack in the office. POTS filter into jack and then cables to phone and modem. One in house, One in cottage.

If your readings change like that then one of those filters could be kaput.
 
Extensions do cause problems on ADSL lines to some degree .
 
This is a splitter? What microfilters can you add to plain copper?

Splitter as shown by MickeyD.

I have previously done some tests on a split as in your case and there was impact to xDSL rates even with micro-filters at the end of the telephone loops. Theoretically, if a POTS/xDSL splitter is used in place of the current junction you should be able to attain better ADSL rates.

I don't know of any splitters which can be put directly on copper, you would probably need to add connectors to the copper or break a splitter apart and use a soldering iron.
 
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