Almost all of my current LNBs are single polarity because I prefer orthomode feeds that allow me to select any polarization from any of the eight receivers connected to my FTA switch matrix. Up until now I have used power inserters on 4x8 powered switches to make sure all of my LNBs get the full 18V they deserve. I found this generated extra wiring and took a lot of unnecessary components, because the powered switches should be capable of feeding 18V out of each port. When I decided to put up a couple of dozen bandstacked LNBs on toroids, I decided enough was enough. The first step was to find a powered 4x8 switch that could pass 950-2150 MHz for the bandstacked LNBs. Many can't. On a hunch I tested a few WNC SWA-48 switches and they didn't roll off significantly. In fact they seem to pass below 950 MHz just fine, too. The other nice thing about the WNC switches is they have removable top and bottom plates held on with screws. That may reduce their water-tightness, but I was planning to install them inside my attic anyway. I popped one open and found separate LM317 regulators providing the voltage for each LNB line. That's perfect because LM317s can be adjusted over a wide range. As stock, two of these are set to 18V and two are set to 13V. A quick calculation found I merely had to tie about 560 ohms across pins 2 & 3 of the '13V' regulators to make them output 18V. Here's how: 1. Take the back plate off the WNC switch. 2. Locate the normally '13V' regulators in the attached photo. Solder on 560 ohm resistors (I had some 1% 562 ohm resistors lying around) to pins 2 & 3 as shown. 3. Power the switch up and verify all LNB connections are outputting 18V. If you want different voltages, the same approach can be used with other resistor values. This mod saves the trouble of wiring up the extra power inserters and having supplies to feed them.