people have posted how you may use an in-line Micro-Filter in lieu of a
POTS Splitter to filter the whole house; saving the cost of purchasing
a POTS Splitter. You may, but you are quite likely asking for trouble.
The inline Micro-Filter is, as you can see in the photo, is a single stage
filter consisting of an inductive device and a capacitance device.
The circuit board is bare. The POTS Splitter is a three-stage filter
and much more capable of separating analog voice/fax/dial-up modem from
the DSL modem. The circuit board has a clear coating to protect it
from the moisture that will be present in an outdoor location. The
POTS Splitter is designed for filtering the whole house, and for use in
an outdoor location.
If you are too close to the Central Office, or the Remote Terminal if
you are serviced from such, the strength of the DSL signal can overwhelm
the lesser in-line Micro-Filter and allow noise to affect analog devices.
If you are too far from the Central Office, or the Remote Terminal if you
are serviced from such, the extra wires, jacks, and filters will cause
a loading of your DSL line that will lower the maximum download speed.
If this goes lowers than your capped speed you will experience lesser performance.