Josh,
First, you are not going to be able to get each antenna and feed line to a 1.1:1 match, can't happen, and you really don't want it to anyway. What's happening is that each antenna is providing an input impedance, which is then added together (not simple addition, by the way) to provide a resulting impedance of close to 50 ohms at the 'T' where the feed line to the radio connects. That 'close to 50 ohms' impedance when connected to the 50 ohm feed line to the radio should yield a usable impedance value near the 50 ohms of the radio, or amplifier's output impedance. That makes the radio/amplifier 'see' an impedance that it can live with (less than 1.5:1, sort of). All this assumes that each antenna (usually a 1/4 wave which is usually something around 30-35 ohms input impedance) plus feedline impedance will yield soemthing around 100 ohms (ideally, just not likely). When these two impedances are paralleled at the 'T' you get a resulting impedance of about 50 ohms (ideally, also not likely). That resulting 50 ohms impedance when connected to the feedline going to the radio/amplifier (50 ohm) will give the radio/amplifier a 50 ohm load, which what you want. You can see that there are a lot of "depends" things (variables) in that, and if most of them are close to what you hope they are then things work out okay. If not, then the trick is to isolate the variable that's causing problems and 'fix'/change it.
Antenna seperation distance. Almost any distance will work to some degree. 'Best' (easiest to to use) distance is close to a 1/4 wave, or about 9 feet. That's usually the easiest to get 'practical' distance between antennas that yields the most directionality. Don't confuse the 6 foot 'electrical' 1/4 wave with this seperation 1/4 wave, they are not the same thing (and I know that's confusing, but it's dealing with signal travel in air instead of metal. Still confusing but only solution to that is a course in electronics theory. Not a bad idea but I sure as @#$% ain't the one to teach it, and this ain't the place for it - lol).
Radiation patterns. The typical phased antennas signal is greatest perpendicular to the plane of the antennas, or broadside to the two antennas. Antennas mounted fore and aft? Max signal off to ~both~ sides. Antennas mounted one on each side, max signal fore and aft. No matter which way you mount them you'll only be pointed wrong half the time, maybe - lol. Bidirectional. That 'direction' can be changed by varying the phase between antennas, which was what the thingy from 'Hygain'(?) did. It isn't quite as simple as the typical dual antenna set up though. Rejection? No idea, never measured it. It'll be noticable, so I'd guess around at least 3db or more, sort of.
The 'T' connector you posted should work just fine. So would most that you could find at Radio Shack (I know, dirty work). 'Amphenol' conncetors are best, others are too, but it's a sure thing with 'Amphenol'. [Except for the '90 degree' turn connectors which are ALL the pits, deals with how they are made, ain't getting into that.]
- 'Doc
PS - Hardest part about trying to explain this stuff is trying to guess what you know/don't know already, and how much 'stuff' your willing to put up with in getting to the finish line. Either the teller or the listener always seems a bit 'dull'. Isn't intended that way, but just how it works out. Sorry 'bout that...
Best advice I can give is to find one of the ham 'Handbooks'. After getting over the normal intimidation of the thing, it's quite informative, has examples of most of this stuff, and gives a pretty good explanation of the 'why' of it. Sound like I'm trying to get out of teaching something? HELL YES! I'm a lousy teacher.
