Combine VHF only antenna w/ Mohu Sky?
 

Hi,
I live in central MA where reception can be difficult. I can pull in most of the Boston channels with my Mohu Sky pointed toward their towers but want to get FOX Providence, RI if possible. This channel operates on VHF 12 while all of the Boston channels are UHF. If I turn my Mohu toward Providence I can get Fox on a clear night but it is very inconsistent. I saw posts here about combining a VHF & UHF (though I know the mohu does both to some degree) antennas.

My thought is, point the Mohu Sky HD toward Boston and then grab something along the lines of an Antennacraft y10-7-13 and point that toward Providence. Is this possible? And if so what do I need?

I currently have a line of coax going up to my mohu on the roof with the "mohu power injector" which looks to be the exact same as the Winegard LNA-100.

If it helps here is my fool report: link
And before people ask I have tried everything from rotating the antenna and changing location to get Fox Boston UHF-31. Though most other Boston channels come in fine Fox UHF-31 will not come in.

Yes, you can do that. The VHF antenna will not be amplified, though, since the Sky's amp is mounted inside the outdoor housing.

Install and aim the VHF antenna so that it works well. If you find that it needs to be amplified, you will need completely separate down-leads and you'll have to install the U/V combiner at the outputs of the respective combiners.

If the VHF antenna is fine as a passive installation, then you can combine the two antennas using either a Radio Shack 15-2586 or our EU-385CF as close to the two antennas as you desire. Do NOT substitute a Holland or TruSpec/PicoMacom (or any other) UVSJ as the two liste above are the only ones known that will pass your pre-amp power THROUGH the UHF side of the device which s what you need.

Reception of a Fox affiliate is a challenge given that two stations, WFXT & WTIC are broadcasting on the same frequency, real CH-31.

You may want to explore alternate mounting height. A high gain antenna with a high F/B (front to back ratio) would also help. The Antennas Direct 91XG would be a top contender based on that criteria. Still, you could face the prospect of needing to take additional steps such as ganging two antennas to improve the F/B.

http://forum.tvfool.com/showthread.php?t=1024

Thank you both for the replies.

While I would love for this to work in a passive install, I am doubting it will. Question though, since the mohu "power injector" is pretty much the same as the Winegard LNA-100, could I possibly still use one cable and pick up an LNA-200, putting the outdoor pre-amp with the VHF antenna, and having the power injector feed both that pre-amp and the one built into the mohu Sky? The "power insterter" that comes with the LNA-200 seems to be the same, I just don't know if it would be strong enough to feed both pre-amps.

FOX has been a tough one for me. There was probably some reason, but why both Boston, MA & CT Fox stations both picked to use channel 31 is beyond me. I guess they figure only a small population (myself included) lives on the boundaries of both signals. I figured early on this interference is probably what is keeping me from getting FOX though there is a hill on the CT side of me so I am surprised the already weak signal doesn't get blocked some by that. Again there is probably more science to this than I know of. I looked at the 91XG but it seems to be very directional and the site itself warns that hilly terrain can be tough. I already have a 2Edge between myself and the Boston stations so with my hilly terrain I may be best sticking with my mohu and trying to consistently pull in VHF-12 from RI. On clear days it comes in fine on its own of the mohu is pointed in the general area, though when the weather gets wet I am out of luck.

You're on your own there. Assuming that the parts are interchangeable probably isn't a wise decision. For example, Winegard uses the identical plastic housing for its LNA100 amp and for the injector for the LNA200. The only physical difference is that one has an integral F-connector and the other has a short coax pigtail. I have no idea what Mohu is using for a power injector for the Sky as I haven't seen one yet.

I know it's not good practice but I am 99% sure that the two injectors are pretty much the same. Below are pics for comparison. I also would also bet that the Mohu Sky HD innards are VERY similar to the Winegard Flatwave Air.

http://www.winegard.com/images/lg_boost_th.jpg http://d3a21r1ohpba23.cloudfront.net...ultimate-9.png

Like I said, you're on your own. Your results will be anywhere from it works okay to an expensive surprise.

The outside shapes and connectors are not what is important The internal electronic components are what matters and you haven't a clue what they might be.

C'mon, "it works ok" not "it works great" haha. I hear you though. Was just considering options. But the above combiners you listed will allow the power to travel to the mohu and the VHF antenna to work passively?

Even if you are lucky enough to have two units w/ identical voltage and polarity, you could exceed the capacity of the power inserter (ma).

There are other problems that could arise, but they would differ, from one unit to the next.

Yeah I hear you. I am going to try a passive install and if that doesn't work bite the bullet and run a 2nd line of coax to the roof and combine in the basement after the amps.

By the way, is the LNA-200 a good amp to use for the y10-7-13?

With a measured noise figure of over 5 dB, there are likely far better choices than that one.

Any suggestions?

Bump on an amplifier suggestion for the y10-7-13?

The RCA TVPRAMP1R preamp is economical and has good performance. It can be used in both strong and weak signal areas.

Thanks! Hopefully it will work for my painfully weak signal area.

Does it come with the power brick or injector for the amp?

Anyone know what hookup the y10-7-13 has? Will I need a converter for hooking up standard RG-6 to it?

The TVPRAMP1R is supplied with a separate power supply which is intended for installation in an area that's dry. The amplifier unit is weather proof so it can be installed on the mast, near the antenna like any other preamplifier.

As I recall, my Y10713 was not supplied with a matching transformer (balun). The antenna output is '300Ω balanced', so you will need to use a standard 300Ω/75Ω matching transformer.

Finally got around to ordering everything up. Let's see how it goes!

Update: The Antennacraft Y10713 is an amazing antenna. I installed it in my attic and used the recommended UHF/VHF combiner and my signal strength (which I know is relative to the TV) went from 0% to 50% with quality at 100%. This was without using an AMP, in an attic, pointing to a station 60 miles away with a 2EDGE. Signal has remained pretty reliable though there was some pixelation when watching one night. Going to play around with spots in my attic as well as try an AMP I have laying around. Going into this I was not expecting much, I am in a pretty bad location for OTA to begin with but I now have a reliable fox affiliate since my local one (WFXT Fox-25) has yet to show a blip of a signal at my house ever after playing around with antenna locations. Odd thing is the other UFH Boston stations like ABC NBC & CBS all come in strong.

So I tried two different Radio Shack amps and it made no difference with my signal strength. Guess it's good my RG6 isn't losing anything but shouldn't I have seen something? Tried back and forth multiple times with the amps and strength was a solid 60% each time.