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Tuning in ATSC reception: Ongoing Mohu frustration

-September 14, 2013

Last November, I shared my experiences trying to obtain robust ATSC reception at my CO residence, using two antennas (an unamplified Moho Leaf upstairs, along with the Mohu Leaf Plus downstairs, the latter containing a 10-15 dB amplifier) and two tuners (a SiliconDust HDHomeRun downstairs, and the tuner built into my Curtis LCD3708A 37" 720p LCD TV upstairs). My conclusion at that time was two-fold:
  • The unamplified antenna upstairs did a better reception job than its amplified counterpart downstairs, though I don't know how much of this has to do with the ~10' vertical placement differential between the two, versus the varying tuners connected to them, and
  • Neither antenna did a credible job of tuning in UHF broadcast sources.

Although I also have cable television service here, my search for robust ATSC reception continues unabated, in no small part because I'm too much of a cheapskate to pay Comcast extra cash for a HD channel package ;-) In mid-November and again in late December, Mohu's PR contact reached out to me with a post-review invitation to try out next-gen products from the company. Specifically, the PR person indicated that "We have just released the Leaf Ultimate, which is an all-new indoor antenna that outperforms our current Leaf Plus." Mohu's website offers only a bit more information on the Leaf Ultimate, the replacement for the no-longer-sold Leaf Plus:

Amplified with Clean Peak™ filter technology: most sophisticated amplifier on the market that removes unwanted RF signals and boosts the ones you want

As you can see from the photo below, the Leaf Ultimate is similar in appearance to its precursors, although the amplifier is now standalone versus being integrated into the coax cable coming from the antenna (the coax cable is also separate, versus integrated, in this product generation):



Before swapping out the Leaf Plus for the Leaf Ultimate, I did a channel scan using the Leaf Plus in combination with the HDHomeRun, coming up with 17 claimed receivable channels and sub-channels:



Certainly my results would be better with the Leaf Ultimate, yes? You'd think, but you'd be wrong. In exactly the same location as its predecessor, I was only able to come up with the three sub-channels associated with physical channel 18, and then only about half the time I tried...scan attempts would often report no channels found:



For grins, I grabbed the unamplified first-generation Leaf from upstairs, again installing it in exactly the same place where the Leaf Plus had previously been located. This time I was able to tune in six channels and sub-channels:



So the amplified Leaf Plus does better than the unamplified Leaf, but the supposedly best-of-all Leaf Ultimate actually does the worst of all. What's going on here? Here's my theory:
  • As previously stated, none of the antennas is able to do a credible job of pulling in UHF broadcasters
  • The Leaf Plus amplifier enables it to tease more VHF signals out of the ether than the unamplified Leaf can, but
  • The further (and unspecified) amplification of the Leaf Ultimate causes signal overload at the HDHomeRun tuner's input stage with some VHF sources, leading to its comparatively inferior performance

Next in the review queue are two similar-to-Mohu-in-appearance antennas from Winegard, the FlatWave series, one unamplified ("Non-Amped") and the other amplifier-inclusive ("Amped"). According to my Winegard contact:

I’ve got a remedy for your Hi-Band VHF problem. Our brand new FlatWave antenna series has a patented element design that actually includes not only UHF but also VHF elements. We focused on Hi band VHF and UHF for this design because the real stat is that approx 75% of the country needs to receive not only UHF but Hi Band VHF also. Some people on the fringe of indoor reception will do best in a window [editor note: that's where mine is installed]. We also offer a clear version that passes light and takes the color of any walls behind it.

We shall see. Stay tuned for next week's report.


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