HD-1080 & HD-4400 Amplified Combination?

[SRT6]

I would like to combine these antennae which will be stacked and pointed in different directions at an included angle of aproximately 55 degrees. HD-4400 will be UHF at about 45 degrees, HD-1080 will be primarily for receiving Hi VHF 7,8 at about 110 degrees, but still need to receive UHF from this diection also. I am at 42.758745 Lat /86.203959 Long.
Questions:
1. Can Winegard dual input pre-amps be used for combining these antennas?
2. If HD-1080 is used on the VHF input, will UHF from this antenna be be blocked due to band pass filter?
3. Why is Winegard discontinuing the 300 ohm input amplifiers? Would not it be a more efficient connection scheme than using 75 ohm baluns off each attenna?

Thanks, I have not fired these antennae up yet.

[winegard]

SRT6 -

I received the following reply from our technicians...

Trying to combine 2 antennas in different direction becomes tricky in that you can cause multiple signals from each channel to appear at the tuner and confuse it. The problem is that we do not know how much of the 45 degree signals will be picked up on the side of the HD-1080 antenna and how much of the 110 degree signals will be picked up on the side of the HD-4400. If the primary signal is not at least 2 to 3 times stronger than the secondary signal the digital tuner have a hard time figuring out which signal to lock onto.

In order to couple these 2 antennas together you will need to use a CC-7870 coupler and this will reduce your signal by -3.5dB (30%) loss. You will loose all UHF signals from the HD-1080 if you hook up the VHF input on AP-2870 dual input preamplifier. Your best bet would be to preamplify each antenna then try combining the signal after the power supplies of each preamplifier. This way you should have a strong enough signal you can afford the coupling loss.

The 300 ohm input preamplifiers was discontinued for lack of demand. You only loose about .5dB of signal in a good 300 to 75 ohm matching transformer. Plus the 300 ohm wire is a non shielded wire which can act as an antenna on UHF and actually cause ghosting or now on digital multiple signals to the tuner.