Follow up: Since OP I bought an amplifier for the square-grid antenna I've had installed in my attic for years. It did help some. Bought and installed a lava motorized antenna. It does ok, but having a motor on it is pretty-much useless, since the controller does not indicate where it's is pointing or what direction it is rotating. Basically it's a set-it/forget-it type. I also bought an SP100 omni-directional antenna. It too does ok and found a few more channels. I do not have a signal strength meter but have one on the way. It, hopefully, will help tune the antenna better than me using only a compass. I will try to mount the omni unit outside and out of sight to the HOA spys. It doesn't look like tv antennas once did. Looks more space-age.....frisbee with a 24" wing on each side 180ð apart.. That installation will be the best I can do given where I live. That will involve a little more work (grounding the mast and grounding the cable-shield). I think my biggest problem with OTA signals has more to do with the 70' Red Oak tree in my front yard tho....

To add to davidandkasies excellent post, for best results the preamp should be as close to the antenna as possible. For a 4-way splitter, you will want something with at least 8 db of gain. Also look for a low noise figure (3 db or less), and doesn't easily overload (100k microvolts or more.) Considering your splitter, coax, and connector losses and such, a Winegard HDP 269, at 12 db of gain might be ideal. More typical is something like a Winegard AP-8700 - which has about 17-19 db of gain. It would also work, but might require a bit of attenuation to avoid overloading your TV sets. A preamp designed to be mounted outdoors on a mast has a separate power supply. The power supply is remotely mounted somewhere out of the weather and sends DC up the coax to power the preamp. You could use something like this. But as davidandkasie says, the power supply will probably want to be on the antenna side of the splitter - since many splitters won't pass the DC through. OTOH, since your antenna is in the attic, there should be a junction box around somewhere were you can install an outlet for an indoor preamp. As far as coax goes, use RG-6 everywhere you can. The new compression connectors are really neat - much better than crimps. But they require an investment in tools. (About $75.) Don't even bother with those stupid 'twist on' connectors.

I too have OTA (Over The Air) channels. I have a roof antenna. Although, it is sitting in my living room at the moment. I really need to find someone to install it on the roof. Anyhow, in Houston, there are almost 90 OTA channels. My antenna that sits in the living room picks up around 75 of them. Half are foreign & religious channels though. What many people don't realize is that with a TV antenna, we can actually pick up true high definition picture. Whereas, cables & satellite services often compress the pictures and what you see on your TV is only what you get from these services. Regardless that you have an HDTV (high definition TV). Anytime someone comes over my home, they're surprise of how crispy clear my TV is. All it is is simply true high definition signal via OTA. Between AntennaTV, MeTV and ION channels, they keep me entertain 24/7. I'm not a big sport fan; thus, paying to watch TV just doesn't make sense to me. I had Infinity and Uverse young salesmen tried to sell me their services. They insisted that their service beat the price of all the others. I repeatedly tell them: No thanks. Then, they asked me: "What do you do for TV?". I simply point my finger up in the air and tell them I watch OTA channels. They had this puzzled look. LOL, these kids had no idea what OTA channels and a roof antenna were. After getting some lengthy explanation, they admitted that they can't beat the price of OTA channels. LOL... these kids...

"Neither Consumer Report or Amazon reviews have proven to be worthwhile due to the reviewers giving 5 stars for something they have owned a short amount of time" Ridiculous statement. Of course CR owns the TVs a short amount of time. TVs become obsolete; should CR rate TVs five years old and no longer manufactured? The TVs are rated on performance. "I would take the advice of a post on here may be better in the television section of garden web over anyone else." That makes no sense. Each person has only one TV; he can't do side-by-side performance comparisons.