The SWM8 Single Wire Multi-Switch is now shipping: Click here.
Single Wire Multiswitch (SWM) technology allows you to distribute satellite and Over The Air (OTA) antenna signals on a single cable. For instance, you can combine your Sat 1, Sat 2, and the OTA cable into one cable. In addition, a house that was wired with a single cable can now have up to 8 tuners anywhere in the house.
The SWM's do work with the TiVo's and other "Legacy" receivers using the legacy ports. So for instance an HR10 would use 2 legacy ports and still use two cables for it's two tuners.
Currently the only SWM Receivers are:
D12 Standard Definition Receiver - Single Tuner
H20 / H21 HD Receivers - Single Tuner
HR20/HR21 DIRECTV PLUS HD DVR - Dual Tuner
+ Older "Legacy" Receiver Tuners must be connected individually to the Legacy ports.
+ The SWM5 can serve up to 5 SWM tuners
plus 2 Legacy tuners
. For example, it might serve (2) HR20's, (1) H20's, and (1) TiVo.
+ The SWM8 can serve up to 8 SWM tuners
plus 3 Legacy tuners
. For example, it might serve (3) HR20's, (2) H20's, (1) TiVo, and 1 older receiver.
+ "SWM" is now used instead of "FTM". Older units may have a label of FTM instead of SWM but they mean the same thing.
Here is the most updated Diagram and Notes on the SWM8 from the HD DVR FAQ
Single Wire Multiswitch (SWM)
Because it is an active device, I saw a jump in signal levels too.
The SWM8 does a great job of combining OTA and satellite on one wire. It can be 1 cable instead of 3 going to your DVR now. You need a good diplexer though to split the OTA back out at the receiver.
Here is the comparison chart: Diplexers