Category: Product Reviews

Useful Gadgets: Antennas Direct ClearStream 2MAX and 4MAX Indoor/Outdoor TV Antennas

If you watch enough late-night television or independent local TV stations, you’ll eventually see an ad where George Forman, former heavyweight boxing champion, smiles at the camera and says, “People are always asking me: George, how do I patent my invention?”

Now, I’m pretty sure NO ONE has ever asked George Forman how to patent an invention, just as NO ONE has ever asked me for advice on how to become a championship boxer. On the other hand, I frequently get asked two questions – “What model of TV should I buy?” and “I want to drop cable TV. Can you recommend a good antenna?”

Lately, my answer to the first question is usually “Buy any TV you like. They’re so cheap now that you can just recycle it at the end of the year if you aren’t happy with it.” (I’m not being facetious: I just got a press release from RCA announcing a 50-inch Full HDTV with built-in Roku software for $499 and I’ve seen basic Ultra HDTV 50-inch sets from Hisense for less than that.)

My answer to the second question is a bit more measured. I need to know details before I can give out any practical advice. Do you want an indoor or outdoor antenna? How far do you live from the transmitter site(s)? What obstructions (hills, buildings, towers, etc) are near your home?

My most recent review of TV antennas focused on indoor models, which generally disappoint (with the exception of Mohu and Winegard). In most cases, my trusty $4.99 Radio Shack bow-tie antenna is more than adequate for that job, and if the signals are a bit weak, a low-noise, medium-gain amplifier fixes the problem. Granted; not a very sexy-looking antenna, but function always trumps form when it comes to pulling in TV stations.

A recent article in the Wall Street Journal details how Millennials seem astonished that “yes, Virginia; it is possible to watch television for free!” And all you need to do is (a) pick up some sort of TV antenna – yes, they still make those relics of the mid-20th century, (b) connect it to that threaded F-connector on the back of your TV set or pick up a USB tuner stick for your laptop, and (c) do a channel scan.

A few minutes later, you’re able to enjoy HDTV content from ABC, NBC, CBS, Fox, The CW, My TV, PBS, and other outlets. On secondary channels like Antenna, Comet, and Me TV, you can enjoy those great old black-and-white and color shows your parents and grandparents watched back in the day, like The Twilight Zone, Gunsmoke, Three’s Company, M.A.S.H. and The A-Team. And of course, your local news and weather (and emergency alerts) is always available, as are NFL games, the World Series, Stanley Cup playoffs, NBA Finals, Olympics, NASCAR and Indy Car racing  (I could go on and on….).

With an increasing number of people ditching expensive pay TV channel packages for fast broadband and video streaming (a/k/a “cutting the cord”); installing an antenna to pick up channels for free seems like a no-brainer. And you can happily ignore the occasional spat between your local cable TV provider and a major TV network over retransmission fees that usually results in a broadcast network channel being blacked out.

Plus, in case of severe weather, you have a Plan B if you lose landline telephone, cable TV, and broadband service. (It happens!) At which point the cellular phone networks get swamped and are often unusable. But you’re a cord-cutting smartie – pick up a battery-powered portable TV and you can stay in touch with weather updates. If you have a generator in your home (like I do), simply switch your TV to the antenna setting and you can continue watching while the utility crews struggle to remove fallen trees and re-string wires.

Ah, what better fun than to sit on your deck on a beautiful summer day and play with TV antennas!


Antennas Direct recently sent me review samples of their new ClearStream 2MAX (MSRP $79.99) and 4MAX (MSRP $149.99) indoor/outdoor TV antennas. (AD brands them as “HDTV antennas,” but that’s misleading marketing – HDTV is a picture format, not an RF transmission format. And some broadcast stations transmit standard definition TV on their sub-channels. (Hey, that UHF bow tie pulls in HD broadcasts, too!)

I’ve tested numerous ClearStream antennas in the past, and just for fun, I pulled a couple out of storage to use in this test for comparisons; the 1V and 2V (no longer offered). I also dug up one of Channel Master’Channel Master’s STEALTHtenna 50 models (MSRP $29.00) and added it to the pile, and to top things off, I included my home-brew ‘ugly duckling” 3-element UHF yagi antenna.

The ClearStream 2MAX antenna under test atop a 10-foot mast.


The ClearStream 4MAX struts its stuff.


Channel Master’s STEALTHtenna joins the fun…


…as did my 3-element “ugly duckling” compact UHF yagi antenna.

The 2MAX and 4MAX antennas are basically loop designs. They should exhibit broadband frequency response across the UHF TV band, although they’re too small to have much gain at low-band VHF (channels 2-6) and high-band VHF (channels 7-13) frequencies. That’s where the single dipole element comes in – it works better for channels 7-13, but is still a bit small for reception of 2 through 6.

Channel Master’s STEALTHtenna is more of a directional design as it is a six-element yagi for high-band VHF and UHF. CM claims 9 dB gain on UHF and 6 dB gain on VHF, compared to the published gain specifications of 2.6 dB on VHF and 8.7 dB on UHF for the 2MAX and 2.5 dB on VHF and 11 dB on UHF for the 4MAX. The low VHF gain figures for the 2MAX and 4MAX are precisely because a single dipole element is being used for VHF – and it has a figure-8 reception pattern front and back.

I’ve never calculated the gain of my ‘ugly duckling’ 3-element UHF antenna, but it would be at least 6 dB since it is directional, but has a wide (75-degree) antenna pattern. Still, it is a useful benchmark for basic TV reception and works surprisingly well, with a full-wave loop driven element resonant around 600 MHz and an aluminum-screen reflector.

Each antenna was placed atop this 10-foot mast and aimed in two directions for the test.


Each antenna was tested with and without the ClearStream Juice mast-mounted preamplifier. (Well, the mast was only 15 feet away from the test equipment…)


Hauppauge’s WinTV Aero-M USB stick receiver, TS Reader software, and a spectrum analyzer performed the critical measurements.


The weather on test day was spectacular – it had dropped into the high 50s the night before and a tropospheric weather duct was present, bringing in strong UHF TV signals from Scranton/Wilkes-Barre PA; over 70 miles to the north. The signals from WVIA-41, WOLF-45, and WNEP-50 were so strong I could pick them up with the 3-element UHF yagi with no amplification! As the morning wore on and the air heated up, the duct quickly disappeared.

I set up everything on my rear deck with two 5-foot Radio Shack mast sections siting in a tripod mount holding up each test antenna. I aimed it north-northwest to pull in stations from Allentown/Bethlehem PA (about 25 miles away) and south-southwest to pull in Philadelphia stations (over 20 miles away with some obstructions). Each antenna was tested with and without a preamplifier (ClearStream Juice, $79.99) to try and pull in a pair of low-band VHF channels (KJWP-2 and WPVI-6), two high-band VHF channels (WBPH-9 and WHYY-12), and a host of UHF stations.

I captured the spectral views for each antenna/amplifier combination and used TS Reader software to decode the MPEG transport stream and verify reception through a Hauppauge Aero-M USB tuner stick. If the station locked up quickly with a low or zero bit error rate (BER), then I checked it off as received. If I saw tiling on the image or a high BER, then reception was considered unsuccessful. I also tuned in selected signals to watch the content and verify reception.

While UHF reception for smaller antennas is generally easy, there are some lower-power stations in Philly that don’t always show up in a channel scan, so I gave bonus points for pulling in two of these stations (WTVE-25 and WGTW-27). I was also very interested to see how each antenna performed with low-band VHF channels – a part of the spectrum that’s particularly susceptible to atmospheric and man –made noise, especially with indoor antennas.

Here’s what the Philadelphia UHF TV spectrum looked like using the ‘ugly duckling’ 3-element UHF yagi with amplification.


The same spectral view as seen with the Channel Master STEALTHtenna and amplifier…


…the ClearStream 2MAX antenna with amplification…


…and the ClearStream 4MAX antenna with amplification.


Just for fun, here’s the UHF spectral view captured with the discontinued ClearStream 1V through an amplifier. If you’re not seeing a big difference in performance across the commercial antennas, welcome to the club.

In general, the easiest signals to capture came from WPVI-6, WBPH-9, WPHL-17, KYW-26, WCAU-34, WYBE-35, WLVT-39, and WFMZ-46 (that last one runs over 5 million watts ERP). KJWP-2, WUVP-29, and WTXF-42 can all be problematic, as are the two lower-power stations mentioned earlier. In addition, WTXF has a repeater in channel 38 in the Lehigh Valley, so I checked for that one as well.

Why’d I test with the Juice preamplifier? The 8VSB transmission system used for digital television in the U.S. has a theoretical minimum carrier-to-noise ratio of 15 dB – but that’s in a perfect environment. In the real world, signal reflections and distortion make it harder for the adaptive equalizers in an 8VSB receiver to pull in a DTV broadcast.

Amplifying the signal at the antenna (not at the TV) boosts the overall C/N ratio and makes it easier for the equalizers to do their jobs. Plus, it provides access to more distant signals: With a 5-element high-band VHF yagi and Channel Master mast-mounted low-noise preamp, I can watch New York City DTV stations that are over 60 miles away – through two ranges of hills.


Table 1 shows the final results for each antenna running ‘barefoot’ – no amplifier. Each antenna gave a good accounting of itself with the 4MAX taking top honors, pulling in 13 stations. Oddly enough, the discontinued 2V grabbed WTVE-25 for a bonus, but still was good for only 11 stations. The ‘ugly duckling’ did about as well as expected since it has zero gain at VHF frequencies, pulling in 7 UHF stations while Channel Master’s STEALTHtenna grabbed just one more.

Table 1. Comparative performance of all antennas without amplification.


A real head-scratcher? The ClearStream 1V (discontinued) came up just one channel short to the 4MAX and out-performed the 2MAX (9 channels) and 2V (11 channels). Go figure! Of course, the 1V and 2V have mesh screen reflectors, giving the antennas some degree of directivity over the 2MAX and 4MAX.

Table 2 shows what happened when a Juice preamplifier was inserted inline, leveling the playing field.  The ‘ugly duckling’ UHF yagi captured 1 VHF and 11 UHF signals – not bad. That tied it with the 1V loop antenna, edging out the larger 2V dual-loop by one station although both of the older ‘loopers’ found the bonus stations. The amplified 2MAX managed to sniff out 14 stations plus two bonus stations for a grand total of 16, tying the amplified 4MAX (it couldn’t pull in WTVE-25).

Table 2. Comparative performance of all antennas using the Juice preamplifier.


But the overall winner in this category was the $29 STEALTHtenna, receiving every possible station in the table including the two bonus channels for a grand total of 17 stations. It tied the 4MAX on the 15 ‘core’ VHF and UHF channels, too. Just goes to show you that a good antenna design doesn’t need to cost an arm and a leg – you could buy 5 STEALTHtennas for the cost of one 4MAX. (Actually, you could buy two STEALTHtennas; mount them on a mast a half-wavelength apart, and run them into a combiner and mast-mounted preamp to add gain to your system.)

KJWP-2 and WPVI-6 as received by the Channel Master STEALTHtenna using amplification. This setup worked very well in the noisy low-band VHF spectrum.


The same channels as seen by the 2MAX antenna with amplification…


…and the 4MAX antenna with amplification.


The discontinued ClearStream 2V might have been a strong performer on UHF channels, but it’s overwhelmed with noise on low-band VHF channels.


To be fair, a difference of one station either way doesn’t really define a “winner” and a “loser” in this test. I might easily have had different results if I moved antennas to either side or changed their elevation. (That’s why each antenna was tested in the exact same location.) I will say that based on my results, I’m not sure you’d need to upgrade to the 4MAX for an additional $70 over the 2MAX – there was a 4-channel difference when both antennas were unamplified, but they tied with the Juice in line.

That’s a lot of extra dough for not much difference in performance, and if you live more than 20 miles from your local TV transmitters the money would be better spent on a mast-mounted preamplifier – especially if you plan to distribute signals to more than one TV through splitters (a two-way splitter will drop signal levels by about 3.5 dB at each port.).

Useful Gadgets: TERK Omni and Turbo Indoor DTV Antennas

I have to give Terk credit for continuing to roll out innovative designs for indoor and outdoor TV antennas.  Going all the way back to 1998, when I tested my first Terk design, there have been some pretty interesting-looking products in their line (not to mention some strange ones, too!).

Unfortunately, the performance of these antennas hasn’t always matched up to their looks, and the new Omni and Turbo indoor models aren’t breaking that mold any time soon. The bar that any indoor TV antenna must overcome is pretty high: They must have gain at the specific frequencies; enough of it to overcome multipath distortion and echoes – a given indoors – and also to provide a sufficiently-high signal-to-noise (SNR) ratio so that reception is free of drop-outs.

The Omni (model OMNITWR, no price yet) is a black plastic tower that stands about a foot tall and has a blue LED illuminating ring on the bottom. Terk calls this an “amplified multi-directional HDTV antenna” which “receives 4K Ultra HD Broadcast” (never mind that there aren’t any yet) and “Supports 1080p.” The packaging goes on to promote free HDTV from the familiar networks (ABC, CBS, Fox, NBC, CW, PBS, and Univision) and proclaims it is “a great compliment to streaming players.”

Well, Terk and I agree on that last point, at least. Free off-air digital TV is a great compliment to streaming channels. If you can get CBS off-air, why pay $8 a month for it? For sports fans, there are still quite a few marquee events that are broadcast on free channels, and for ‘retro’ fans, more and more secondary minor channels like Antenna TV, Comet, and MeTV are full of classic old TV shows (many in thrilling black and white!) from the 1950s, 1960s, 1970s, and even the 1980s.

Elsa can’t figure out if the Omni is a scratching post or not.

As for Terk’s other claims; antennas pull in RF signals, such as TV channels. Those channels can carry digital information in the ATSC format in the U.S. or in the DVB format used elsewhere in the world. The demodulated broadcast signal can be standard definition (480i) or HD (720p and 1080i). It’s the TV that demodulates the signal, NOT the antenna – all the latter does is receive the RF channel.

So technically, the Omni (and any other indoor or outdoor antenna, for that matter) can receive 4K broadcasts. They could also receive 1080p HD broadcasts, although that format isn’t used by any television station. Yes, the $4.99 bow-tie antenna I use in all of my tests could also receive a 4K broadcast! (How’s that for mixing contemporary with retro?)

Terk’s Trinity Xtend Turbo antenna (Model WITRIAC, $129.99) is another indoor antenna design that is shaped like a book. You can lay it flat or mount in vertically for TV reception. But it does double duty as a WiFi extender, working with dual-band (2.4 and 5 GHz) systems that use the 802.11ac channel-bonding protocol. So you can watch TV and extend your WiFi range, too!

The shipping box touts “802.11ac up to 3X faster than 802.11an.” Well, that should be the case, as you can bond two, three, and even four channels in the 5 GHz band to increase data speeds, but that’s a WiFi protocol not related to DTV reception. As before, Terk claims this antenna will receive 4K broadcasts and supports 1080p, and we don’t need to go down that road again.

But there’s one additional claim that was hard to swallow: A reception range of 65 miles, which would be some manipulation of the laws of physics for such a small antenna! I’m hard-pressed to receive signals that far away using a combination 5-element VHF and 15-element UHF antenna system equipped with a 24 dB mast-mounted preamplifier. But I suppose it’s possible that reception over that distance might be possible if (1) you lived on a mountaintop with a long view to the horizon, (b) happened to be watching UHF TV channels during a tropospheric ducting event, or (c) were watching terrestrial TV on the international space station.

I tried the Trinity Xtend horizontally polarized…

…and vertically polarized.


All’s fair in love and war, so I decided to test both antennas against my reference bow tie antenna. There’s a sweet spot in my 2nd floor home office where DTV signals from Philadelphia are strong enough to be captured with an indoor antenna, so I ‘borrowed’ my cat’s elevated perch and use that to support all of the antennas. Just for fun, I dusted off an amplified Mohu Leaf to compare tests, and to provide a bit more ‘kick’ to the bow tie, I pulled out the Antennas Direct ClearStream JUICE preamp so that all antennas were playing on a more level field.

Each antenna was placed in the ‘nest’ and aimed for best-looking waveforms on a spectrum analyzer. Then, I scanned up and down the band to find which channels were received reliably, i.e. that is for at least a minute with no dropout. In the Philly market, we’ve got a couple of low-band VHF stations, a few high-band VHF broadcasters, and more than a few UHF signals that should be easily received.

Laugh if you want at this ancient antenna design, but it can run circles around upstarts!


Table 1. A comparison of all the antennas under test. None of them could pull in WTXF on channel 42.

Table 1 shows the results. I was quite surprised by how well the bow tie performed, but perhaps I shouldn’t be. This classic design more than holds its own repeatedly in tests against more expensive models with gimmicky packaging, and it’s over 60 years old. With the JUICE preamp, it pulled in eight out of ten stations, missing WBPH-9 and WTXF-42. (None of the antennas could help Fox’s signal, despite it looking pretty clean and strong on my analyzer.)

2nd place went to the UHF bow tie without the preamp, which hauled in seven stations. Not bad for $4.99! Mohu’s time-tested Leaf with external amplifier was right behind, providing reliable reception of six out of ten stations. Terk’s Omni was not up to the task even after I tried a second position for it, pulling in four out of ten stations the first time around and three of ten on the second try. In its defense, it did snag WLVT-39 from Allentown, which only the amplified bow tie could match.

Compact antenna designs will have trouble with low-band VHF reception.  KJWP-2 and WPVI-6, as picked up by the amplified bow tie…

…are basically ‘missing in action’ on the Terk Omni antenna.

As for the Trinity Xtend? Best to use it as a WiFi extender and forget about DTV reception altogether, unless you live very, very close to the transmitters. No matter which way I oriented it – vertically or horizontally – it could only pull in two stations reliably (WYBE-35 and WFMZ-46) and neither of them is affiliated with a major network. (So much for the claim of 65-mile reception.) My location is around 25 miles from the Roxborough TV towers and has moderate multipath, but not so much that the average indoor antenna can’t pull in at least five stations.

As for the WiFi extender part; it works quite well. I downloaded the Terk Extender app from Google Play and it didn’t take long to make the connection while following the app’s instructions, boosting 5 GHz signal strength by a few decibels in the farthest parts of my house. So you may still find that part of the product useful if you are strapped for range.

Terk’s Trinity Xtend created a ton of spectral noise on high-band VHF channels 7 through 13…

…that wasn’t seen at all when using the amplified Mohu Leaf.

Here are channels 17 through 46 as picked up by the amplified bow tie.

The same channels using the Terk Omni…

…and the Terk Trinity Xtend, lying flat (horizontally polarized).


As you’ve seen in previous tests, there are some really good indoor antennas for sale that won’t break the bank. Winegard and Mohu both offer indoor panel antennas (passive and amplified) that should pull in the majority of stations in your area if you are no more than 30 miles from the TV transmitters. Radio Shack doesn’t sell UHF bow ties anymore, but Amazon shows the ANTOP amplified bow tie for about $28 – a little pricey in my book, but having the amplifier is a plus.

There’s a catch, though. The recent FCC spectrum auction just concluded and it appears that all UHF channels above 38 will be re-allocated for other uses. This means there are plenty of TV stations that will have to relocate, and some of them will wind up in the noisy, harder-to-receive low-band VHF channels from 54 to 87 MHz. Antennas must have more and longer elements to work at these frequencies, so super-compact designs aren’t going to cut it in the future.

With that in mind, I can’t recommend either of the Terk models for indoor reception – not when a five-dollar piece of bent wire can outperform both of them. Oh well; better luck next time…

USEFUL GADGETS: Three Antennas and a Preamplifier for Cord-Cutters

The cord-cutting landscape has changed considerably in the past twelve months, and it’s no longer a fad, but a growing trend as more and more consumers decide that they can get by just fine without expensive pay TV channel packages.

In fact, Comcast reported yesterday that they now have more subscribers for broadband service than for pay TV channels, which accords greater importance to Comcast’s failure to acquire Time Warner: The combined companies would have controlled broadband distribution to a disproportionate number of U.S. homes.

While Internet service is the key part of cord-cutting, free over-the-air television still pays an important part. Think of the Super Bowl, the NHL Stanley Cup and NBA championships, and the NCAA Final Four championship game.

But there’s also a lot of good programming on free TV right now. In recent months, my wife and I have used our Channel Master DVR+ and TiVo HD to time-shift and watch The Blacklist, American Crime, Brooklyn 9-9, The Good Wife, 60 Minutes, American Odyssey, CSI, Blackish, Saturday Night Live, and Mr. Selfridge (plus a host of one-time PBS programs).

Throw in some Netflix streaming (House of Cards) and there’s plenty to watch without Big Cable. So a balanced cord-cutting approach should incorporate both broadband and terrestrial broadcast TV.

To get the former, you need a fast Internet connection and a late-model Wi-Fi router. To get the latter, you only need some sort of antenna to connect to your television or receiver/DVR, like the Channel Master box, TiVo’s Roamio, Tablo, or Mohu’s new Channels product.

Blessed with a few days of nice weather, I decided to excavate my pile of review products and found three antennas patiently waiting for testing. The first was a rather odd-looking design from HD Frequency, called the CC Aerowave ($49 with 12’ cable from It resembles a small window with a 75-ohm coaxial balun attached to the inner corners of two panes.

The second antenna came all the way from Australia and goes by the name HD Quad ($39.99 from It’s a flexible, transparent antenna with UHF collinear elements, not unlike many other antennas I’ve tested.

The last antenna is a bit larger and is a six-element VHF/UHF yagi, and comes from Channel Master. The StealthTenna 50 (CM3010HD, $29.00 from can be mounted indoors or outdoors. It’s small enough to sit in a closet or attic space, or even in a room – think of it as functional art.

I also found a new inline signal preamplifier from Antennas Direct. The Juice UHF/VHF Amplifier ($79.99 from can be used inside or outside and provides about 18 dB of signal boost with a low noise figure, which is real handy in areas where TV reception can be problematic. (Successful digital TV reception is all about signal-to-noise ratio!)

The tried-and-true bowtie antenna under test. Note the high-tech antenna mount.

The tried-and-true bowtie antenna under test. Note the high-tech antenna mount.

The HD Quad under test.

The HD Quad under test.

The CC Aerowave under test.

The CC Aerowave under test.

Channel Master's StealthTenna 50 under test.

Channel Master’s StealthTenna 50 under test.


For this round of testing, I dusted off my tried-and-true UHF bowtie antenna, once available from Radio Shack but largely ignored by retailers today. (Seriously – how many of them want to sell a $5 TV product?)

I set the bowtie up on a folding table in my home office and attached it to a large cardboard box with masking tape. While that part of the test was decidedly low-tech, I then connected the antenna lead into a two-way splitter, with one leg going to a spectrum analyzer and the other going to a Hauppauge Aero-M USB tuner, connected to my Toshiba laptop.

This arrangement allowed me to see the actual waveform and signal strength of each TV station under test. I could then verify successful reception with the Aero-M, and to close the deal, look at the actual MPEG-2 video stream from each station using TS Reader. These three measurements gave me a very concise report on the performance of each antenna.

If you go back to my last round of testing in November of 2014, you’ll see that I used the same antenna position (different box, though!) and same test gear. The only possible differences in testing would come from the amount of foliage on nearby trees, as my house is partially blocked from the Philadelphia/Roxborough antenna towers over a20+ mile path. (In other words, an ideal site for indoor TV antenna testing!)

The Philadelphia TV market is unique in that it has two high-power, low-band VHF TV stations – KJWP (IND) on channel 2, and WPVI (ABC) on channel 6. There are only 40 or so low-band DTVs in operation nowadays as that part of the RF spectrum is susceptible to impulse noise and strange propagation enhancement. Antennas that work well from channels 2 through 6 (about 54 to 88 MHz) are also very large – a half-wavelength dipole for channel 6 needs to be about 68 inches long!

There’s also one high-band VHF operation on channel 12, WHYY (PBS). The rest of the Philly DTV stations are active on the UHF band, starting at channel 17 (WPHL) and ending at channel 42 (WTXF (FOX)). In addition, I can easily pick up three DTV stations from the Allentown area: WBPH-9, WLVT-39 (PBS), and WFMZ-46 (IND). There’s even a repeater for WTXF on channel 38 that shows up on my home antenna array, plus WNJT-43 in Trenton.

The performance of each antenna was verified with an AVCOM spectrum analyzer, Hauppauge Aero-M USB stick receiver, and TS Reader software.

The performance of each antenna was verified with an AVCOM spectrum analyzer, Hauppauge Aero-M USB stick receiver, and TS Reader software.


I picked a handful of stations to verify reception: WPVI-6, WBPH-9, WHYY-12, WPHL-17, KYW-26 (CBS), WUVP-29 (UNI), WCAU-34 (NBC), WYBE-35 (IND), WLVT-39, WTXF-42, and WFMZ-46. Any of these antennas would be doing an outstanding job if they grabbed all of these stations, as their signal levels vary widely and there’s about 113 degrees directional offset between the Roxborough and Allentown antenna towers.

The first measurements were made with the bowtie, but unamplified and with the Juice amplifier connected. I then repeated these measurements with the HD Quad, CC Aerowave, and StealthTenna 50; again, unamplified and amplified. (I’ll have separate comments at the end of this article on the performance of the Juice amplifier.)

Perhaps the toughest signal to pull in is WPVI on channel 6. Two of the review antennas aren’t really designed for low-band VHF reception, but WPVI runs quite a bit of power and manages to get picked up by brute force on many antennas. (None of the test antennas could pull in KJWP-2 reliably). The rest of the stations aren’t quite as challenging to pull in.

Table 1. Here's how each antenna performed with 11 VHF/UHF  test channels.

Table 1. Here’s how each antenna performed with 11 VHF/UHF test channels.

Table 1 shows the results of my tests. Amplifiers do make a big difference, and helped the lowly bowtie antenna and StealthTenna 50 capture first place with 9 out of 11 stations received reliably (i.e. no drop-outs for at least a full minute). To be fair, the StealthTenna 50 is a much larger, directional antenna than the CC Aerowave and HD Quad, both of which should behave like dipoles with classic figure-8 patterns.

Table 2 ranks the antennas by performance. The bowtie by itself wound up in a three-way tie for second place with the amplified HD Quad and bare-bones StealthTenna 50, grabbing 8 out of 11 signals. Following behind was the amplified CC Aerowave, having received 7 out of 11 stations successfully and the bare-bones HD Quad with 6 out of 11 stations.

Table 2. And here's how each antenna/amplifier combination ranked after the tests.

Table 2. And here’s how each antenna/amplifier combination ranked after the tests.


The Aerowave was a puzzler. By itself, it only received one station – WFMZ on channel 46. I experimented with laying it flat and orienting it at right-angles to the Roxborough antenna farm to try and improve reception, and oddly enough, both of these alignments were more successful than simply positioning the antenna with its face in the correct compass heading. Lying flat, it picked up 4 of 11 stations successfully, while angled at 90 degrees, it grabbed 6 of 11.

The literature supplied with the Aerowave says you can “position the antenna in any desired location,” but based on my results, you may be futzing with it for a while to get the best reception – something I didn’t have any problems with when using the Mohu Leaf, Ultimate, and Winegard FlatWave antennas last November.

Just how much difference does an amplifier make? Here's a view of channel 2 through 6, as received by the bowtie antenna, unamplified. WPVI's signal on channel 6 is at the center of the screen.

Just how much difference does an amplifier make? Here’s a view of channel 2 through 6, as received by the bowtie antenna, unamplified. WPVI’s signal on channel 6 is at the center of the screen.

And here's the spectral view with the Juice amplifier inline. You can actually see KJWP's signal on channel 2 now (far left).

And here’s the spectral view with the Juice amplifier inline. You can actually see KJWP’s signal on channel 2 now (far left).



Antenna Direct’s Juice amplifier worked much better than expected. Its specifications call for 17.5 dB of gain on VHF channels and 19 dB of gain on UHF channels. (10 dB = 10 times the signal strength, with each 3 dB in gain doubling the previous signal level.) The amplifier’s noise figure was specified as below 2 dB in the VHF bands and below 3 dB in the UHF bands.

In my tests, the Juice boosted WPVI’s signal on channel 6 by about 15 dB and raised the noise floor from about -87 dBm to -85 dBm – or 2 dB, as the specifications claim. All amplifiers generate noise, and a good design will keep that to a minimum to avoid spurious signals and interference to desired signals. (Cheap amplifiers won’t!) Performance was comparable on channels 9, 12, and even 17, where I saw signal levels increase by about 18 dB.

At the high end of the UHF band, I saw an improvement of 20 dB with an increase in noise figure of about 2.5 dB, using WFMZ’s powerful signal on channel 46 for testing. That’s excellent performance for a UHF amplifier and rivals that of the Channel Master Titan-series mast-mounted amplifiers I’ve been using for years. (Titan 2 VHF/UHF 16 dB $65.00, Titan 2 VHF/UHF 30 dB $69, both available from

I don’t have any data on the Juice’s resistance to intermodulation signal distortion (or overloading from very strong in-band and adjacent-band signals), other than to say that the dozens of very strong FM radio carriers that also broadcast from Roxborough didn’t create any reception issues for me with channel 6 when the amplifier was inline.

Here's a spectral view of WBPH-9 and WHYY-12 with no amplification...

Here’s a spectral view of WBPH-9 and WHYY-12 with no amplification…

And here are both channels after turning on

And here are both channels after turning on “the Juice.”


Here is a view of the UHF TV spectrum from channel 17 to channel 46, as received by the Aerowave with the Juice amplifier. (I could only pick up one signal without amplification.)

Here is a view of the UHF TV spectrum from channel 17 to channel 46, as received by the Aerowave with the Juice amplifier. (I could only pick up one signal without amplification.) Many of the TV signal waveforms are quite distorted, which makes the job of the adaptive equalizers that much harder.

Here's the same view of the UHF TV spectrum, this time received by the HD Quad equipped with the Juice amplifier.

Here’s the same view of the UHF TV spectrum, this time received by the HD Quad equipped with the Juice amplifier. Note that the TV signal waveforms are somewhat cleaner with less multipath distortion.

One more look at the UHF TV spectrum, this time through the elements on Channel Master's StealthTenna 50 and Juice amplifier.

One more look at the UHF TV spectrum, this time through the elements on Channel Master’s StealthTenna 50 and Juice amplifier. Most received channels are very clean with little multipath distortion.

Finally, the same UHF TV spectrum, this time as received by the lowly bowtie, again with

Finally, the same UHF TV spectrum, this time as received by the lowly bowtie, again with “Juice.” Amazing how well such a simple antenna works, isn’t it? That big spike on the far right is WFMZ-46, whose operating frequency is close to resonance with the half-wave loop created by the bowtie antenna. Hence, the very strong signal. (At one time, channel 46 was near the middle of the UHF band, believe it or not!)


It is amazing how little antenna you need to achieve indoor TV reception. My location is sub-optimal in this regard, given my distance to Roxborough and the number of obstructions in my path.

Yet, with just a $5 bowtie antenna, I was able to receive eight TV stations reliably (5 from Philadelphia and 3 from Allentown), including all major networks (CBS, NBC, ABC, Fox, and PBS). Adding the Juice amplifier brought in one more station, and probably fiddling with the bowtie position would have captured the remaining two on my list.

Channel Master’s StealthTenna 50 isn’t exactly small, but you can put it in tight locations indoors for reception, such as a townhouse attic. You can even install it on top of a shelf, or in a closet, and with an amplifier, it will do an excellent job – just use one of the many TV reception Web sites ( is the best) to determine the compass heading and where to aim your antenna.

The HD Quad behaves like many other collinear antenna designs I’ve tested. It’s transparent, so you can hang it in a window, and it is a better performer on UHF channels than on VHF. Add an amplifier to it and you may grab a few more channels. One bonus – you can roll it up and take it with you on trips, as I often do. Hook it up to a USB tuner stick and you can watch local HDTV on your computer in hotel rooms.

The CC Aerowave was, to put it mildly, a disappointment. I even tried moving it to different locations, using the spectrum analyzer to peak the signal and see if I could improve those reception numbers. No dice! Some signals that wouldn’t come in at all were now just intermittent with frequent dropouts and frozen images. Adding the Juice amplifier didn’t help much, so I can’t recommend this antenna.

Finally, Antennas Direct’s Juice amplifier is a solid performer and delivers the goods. A noise figure approaching 2 dB in the UHF TV band is excellent performance for the price. There is a puzzler, though – although this amplifier is obviously weatherized, it doesn’t come with a mounting bracket for installation on a mast, which is the best place to out it to overcome signal loss and noise in the antenna downlead. Something for the AD folks to figure out…

Antennas, Antennas, On The Wall…Who Has The Best Reception Of Them All?

It’s been a L-O-N-G time since I conducted tests of indoor TV antennas. More than a year and a half, to be exact. Yet during that time, various samples have been showing up at my door to be added to the “eventually get around to it” pile in my lab.

Well, I eventually DID get around to it. Some downtime this week gave me the motivation to haul out all of those production samples, set up my spectrum analyzer, and also give Channel Master’s new DVR+ ATSC receiver/DVR a workout.

Unlike my past tests, which took place mostly in northern New Jersey, I opted to stay at home this time and give each of the contenders a shakeout in my upstairs office. Indoor DTV reception at my house is by no means easy – my location is over 20 miles from the Philadelphia (Roxborough) TV towers, and according to, I have a 2-Edge path, meaning there are some hills in the way.

Still, there’s enough RF coming into the room to make this test worthwhile. And my timing couldn’t be better, as numerous research reports and news stories show that, slowly but surely, an increasing number of homes are “cutting the cord” and using a combination of free, over-the-air TV with Internet streaming to get their daily fix of video.

A recent report by The Diffusion Group shows that 14% of all broadband homes don’t subscribe to pay TV, up from 9% in 2011. The report states that about 75% of U.S. households now have broadband service, so that means 13 million homes are doing just fine without the likes of DirecTV and Comcast.

Significantly, 2013 was the first year that pay TV companies saw a net loss of subscribers, even though it was only several tens of thousands. But that result flew in the face of experienced analysts who predicted only a few years earlier that consumers would never give up on cable and satellite television subscriptions.

Funny thing about that: At some point, the monthly cost of pay TV channel packages got so high that people reached their breaking point and said, “Enough!” It’s no surprise that Netflix has more subscribers than Comcast, Time-Warner, or any other MSO (50 million and growing in the U.S.). And it’s even less of a surprise that HBO and CBS announced video streaming services last month to reach cord-cutters: They’ve clearly read the writing on the wall.

While those stories are compelling, they’re beyond the scope of this review. So let’s refocus on the task at hand, which is to determine how well each of the test antennas performed with the DVR+.


Mohu, who has developed some pretty clever antenna designs, sent along their Leaf Metro ($24.99) several months ago. This compact package bears a remarkable resemblance to the trusty UHF bow-tie antenna that decorated so many old tube TVs back in the day, and which was eventually dropped from most product lines because (a) it was too inexpensive, and (b) it didn’t look cool enough.

Mohu’s Leaf Ultimate ($69.99, now called the Leaf 50) has also been sitting on the shelf for a while, and I did hook it up for one of my previous antenna tests. Unlike the Metro, the Leaf 50 is an amplified design and uses an external preamp cartridge that installs in-line and uses either USB power from your TV or a supplied wall transformer.

Mohu's Leaf Metro is very reasonably priced and doesn't take up much room.

Mohu’s Leaf Metro is very reasonably priced and doesn’t take up much room.

The Leaf 50 (formerly known as Prince - no, wait, the Leaf Ultimate) is a solid performer and makes this box look good...

The Leaf 50 (formerly known as Prince – no, wait, the Leaf Ultimate) is a solid performer and makes this box look good…

Rounding out the Mohu triumvirate is the Curve 30 ($49.99), another rectangular-shaped flat antenna that sits on a shelf with a supporting bracket. It doesn’t use an amplifier and is intended for close-in (30 miles or less) operation.

From Antennas Direct, we have the ClearStream Eclipse ($59.99) with inline amplifier. It’s not much more than a tapered loop, but what’s unique about this design is the adhesive attached to the front of the loop: Simply peel off the protective backing and stick it on a window. Or wall. (Or an annoying relative who’s fallen asleep on the couch.)

Mohu's Curve makes a better interior decoration than antenna in my tests.

Mohu’s Curve makes a better interior decoration than antenna in my tests.


The ClearStream Eclipse can stick to just about any surface.

The ClearStream Eclipse can stick to just about any surface.


The FlatWave Amped works very well and its motives are transparent.

The FlatWave Amped works very well and its motives are transparent.

From Winegard, we have the FlatWave Amped ($64.99), a flexible multi-band antenna with preamplifier embedded in the housing, right where the mini coax attaches. Like the Leaf 50, the FlatWave Amped can be attached to just about any non-metallic surface or just hung on a wall.

Finally, just for fun, I threw in an RCA ANT1050 ($12.99) that I had replaced with a Mohu Leaf earlier this year for a friend’s sports collectibles store. This is a strange-looking design, but is basically a pair of folded dipoles in a flexible plastic housing that you can attach to just about any surface.

I wanted to call this the

I wanted to call this the “BatTenna.” Wonder why…


OK, the bow tie doesn't look like much, but it will give you hours of enjoyment - much more than a $3.99 latte macchiato!

OK, the bow tie doesn’t look like much, but it will give you hours of enjoyment – much more than a $3.99 latte macchiato!

And for even more fun, I dug up one of my trusty UHF bowtie antennas to use as a “control” for all of my tests. When Radio Shack used to sell these, they cost all of $3.99 a pop. And therein lies the problem – there’s just no money to be made selling these anymore; not when you can get ten times that amount of money for a flexible antenna design.

Part of my test rig, consisting of my trusty Toshiba laptop and an AVCOM PSA2500C spectrum analyzer.

Part of my test rig, consisting of my trusty Toshiba laptop and an AVCOM PSA2500C spectrum analyzer.


For this test, I went with a simple but reliable methodology: I set up the bow tie antenna on a small table, in a spot where my spectrum analyzer indicated good signal levels on VHF and UHF. The feed from the bow tie went to a two-way splitter, and two identical 10’ lengths of RG-6 connected from there to the DVR+ and to my analyzer.

After running a channel scan on the CM DVR+, I “looked” at each received channel with the analyzer (and captured numerous screens as JPEGs for reference). Then, I switched the antenna feed over from the analyzer to my Hauppauge Aero-M receiver (plugged into my laptop) and used TS Reader to look at the MPEG stream from each station that was successfully received. If I saw nothing but green bars and a low bit error rate (BER), the station was logged under the “Yes” column. If I saw tiling or signal break-up, it was logged as “Int” for intermittent. And if the station didn’t come in at all, or only briefly, it was pushed to the “No” column.

After testing the bow tie, I repeated this procedure for each review antenna. The Curve antenna used its own support in the same test location, but all other antennas were attached with masking tape to a cardboard box to hold them in place in the “sweet spot.” Not elegant, but effective. (I didn’t remove the adhesive from the ClearStream Eclipse.)

This was about as fair as I could make the test. No antenna was positioned in a more favorable location than any other antenna – I just picked a spot, attached or stood up each antenna, connected it, and tried to watch TV stations, just like the average person would at home. Except they wouldn’t have had the advantage of an analyzer to find the best place to set up.


After logging plenty of transport streams, switching through channels, and grabbing analyzer screens, I came up with the results shown in Table 1. Depending on where you live in the metro Philadelphia area, there are 16 to 18 separate digital TV stations that can be received indoors. Three of them are in the Allentown/Bethlehem area, and one (WNJT) is in Trenton, NJ.

Amazingly, I found 11 stations that were consistently strong with most models – not all – and decided to use those for my test: WPVI-6 (in the no-man’s land of low-band VHF), WBPH-9 and WHYY-12, WPHL-17, KYW-26, WUVP-29, WCAU-34, WYBE-35, WLVT-39, WTXF-42, and WFMZ-46. WBPH-9, WLVT-39, and WFMZ-46 are all up in Allentown, and the rest of the signals come off the Roxborough towers. (Note that the channel numbers given are for each station’s physical (RF) channel, NOT their virtual channel. For example, KYW uses channel 3, while WTXF uses channel 29 and WFMZ uses channel 69. )

Table 1. Each antenna was tested with 11 different TV stations. VHF stations are listed in yellow, while UHF stations are listed in green.

Table 1. Each antenna was tested with 11 different TV stations. VHF stations are listed in yellow, while UHF stations are listed in green.

A few other stations popped up briefly during scans, but none of the antennas could pull any of these in consistently. I left them out of the test. Even the DVR+ was able to read and capture some elementary PSIP information for these stations, like their virtual channel table (VCT) and call sign. But capturing basic PSIP information doesn’t mean reception was successful.

The most surprising thing I learned from this round of tests was that the cheapest antenna – the bow tie – was also the most reliable. This design was really intended for reception of UHF stations and was intended to clip on to an extended rabbit ear. Yet, it pulled in ten of the eleven test stations without a hitch, having trouble only with WPVI on channel 6. That’s not a surprise at all, given how inefficient a bow tie would be at 86 MHz! (And it was only $3.99!)

WPVI's signal on channel 6 (center of display) was all but nonexistent on the Metro...

WPVI’s signal on channel 6 (center of display) was all but nonexistent on the Metro… well as the Mohu Curve...

…as well as the Mohu Curve…

..and Winegard's FlatWave Amped.

..and Winegard’s FlatWave Amped.

There was a two-way tie for 2nd place between the Leaf 50 and FlatWave Amped. Again, not a surprise – both of these antennas have fundamentally good designs based on collinear elements, and their built-in preamplifiers raised signal levels sufficiently to provide a strong signal-to-noise (SNR) ratio. That’s critical for DTV reception, especially with multipath! The Achilles Heel for both antennas was VHF reception; specifically, WPVI-6 and WBPH-9. Channel 12 locked up beautifully as did all of the UHF stations.

The Leaf Metro, which physically resembles a bow tie, came in third with eight stations received successfully and three intermittently. Oddly, those three stations were WBPH-9, WUVP-29, and WTXF-42; it wasn’t an either/or VHF/UHF thing. Maybe some more futzing around with antenna placement would have cleaned things up. But you can’t complain for $30 with this model.

The ClearStream Eclipse and the RCA ANT1050 were both disappointments. Each antenna only pulled in seven solid signals, all in the UHF band. Channel 6 was a no-show on the ANT1050 and troublesome on the Eclipse, and vice-versa for channel 9. The Eclipse, even with an amplifier, couldn’t handle channel 12, but the ANT1050 was happy with it. However, the ANT1050 couldn’t lock up WCAU’s NBC signal on channel 34 (ironic, considering what was once RCA used to own what was once NBC!).

Here's a view of the UHF spectrum from channel 14 through 51, as captured with the ClearStream Eclipse.

Here’s a view of the UHF spectrum from channel 14 through 51, as captured with the ClearStream Eclipse.

The same spectrum, as seen through the FlatWave Amped.

The same spectrum, as seen through the FlatWave Amped.

And once more with the Leaf 50 (Ultimate). Not much difference between the three - at least what meets the eye...

And once more with the Leaf 50 (Ultimate). With UHF stations, this antenna had an 8 – 10 dB edge over the FlatWave and 3-4 dB over the Eclipse.

The Mohu Curve, bringing up the rear, was to be truthful kind of a flop. It only snagged five stations successfully – two on VHF and three on UHF – while passing on some easy, strong channels like WPHL-17 and WCAU-34. It also had trouble with WPVI’s broadcast on channel 6.

Again, it might take some futzing around to improve reception with this model, which is probably better used within a 10-to-15-mile-radius around the TV towers and not 15+ miles away. This isn’t the first time I’ve tested a decorative or camouflaged antenna – RCA had a curved picture frame model about ten years ago – and they usually come up short for some odd reason.


OK, everyone can stop nagging me now. I tested every antenna I could find, save for an Australian model that must have come in some time ago and had a PAL-type RF connector for which I had no appropriate adapter. Most of these antennas deliver the goods: I’ve always been a big fan of the basic Mohu Leaf design, despite its lack of gain at VHF frequencies. It’s unobtrusive and works very well.

Winegard’s FlatWave, the answer to the Leaf, also pulls its weight. Both it and the Leaf scored highly in my last test of indoor antennas in March of 2013. (Wow, was it REALLY that long ago?) And things only got better with the amplified versions of each model. I didn’t see a significant degradation of the noise floor here when they were switched on (< 2 dB) and they made a difference on the weaker signals. Use either of these if you are 15 – 30 miles out from the TV transmitters and have a reasonably clear reception path, i.e. maybe a small hill or some buildings in the way.

The ClearStream Eclipse amplifier clearly has some noise issues in the high VHF band (and possible spurious emissions).

The ClearStream Eclipse amplifier clearly has some noise issues in the high VHF band (and possible spurious emissions).

In contrast, Mohu's Leaf 50 is clean as a whistle from channels 7 through 13.

In contrast, Mohu’s Leaf 50 is clean as a whistle from channels 7 through 13.

The Metro has everything – good performance in a small, inexpensive package. I’d recommend this one for city dwellers, and you shouldn’t need any additional amplification. Closer to the transmitter, it should pick up low-band VHF stations nicely, but since there are only about 45 of them in the entire country, that’s not a big issue for the average user.

I can’t recommend any of the last three models, given how many strong stations they couldn’t pull in. The Curve is best used by city dwellers or close-in suburbs, but only if you want to make a fashion statement. Otherwise, go with the Metro and stick it on the wall or in a window. The ANT1050 is certainly cheap, but missed too many easy stations. And the Eclipse is clearly challenged with low-band and high-band VHF reception.

Still, isn’t it amazing how well the bow tie antenna worked? If you can’t find one at a flea market or surplus store, you can make your own easily enough – there are several Web sites that show you how to do it. And your cash outlay will be minimal. Gosh, $3.99 won’t even buy you a tall coffee at Starbucks these days…


This product isn’t getting as much attention as it should. The super-flat DVR+ (not much thicker than a Leaf or FlatWave) has a full ATSC receiver and dual DVRs. It uses the program guide transmitted by each digital TV station to show you what’s on and to set up recordings.

Two accessory USB ports are provided for a Wi-Fi adapter and external storage (internal storage of 16 GB amounts to only about 2 hours of recording). There’s also an RJ-45 port for wired Ethernet connections, helpful when your box does a software update. The connection to your TV is through HDMI with embedded audio, and a separate optical port is provided for AV receivers.

Channel Master's DVR+ has such a low profile that you'll probably overlook it at first glance.

Channel Master’s DVR+ has such a low profile that you’ll probably overlook it at first glance.

In speed tests, the LG TV was a lot faster at scanning for active channels. But the DVR+ held its own with weak or fluctuating signals.

In speed tests, the LG TV was a lot faster at scanning for active channels. But the DVR+ held its own with weak or fluctuating signals.

The DVR+ isn’t nearly as fast at scanning for channels as the LG 47” TV I have in the same room, but it eventually finds them all. The receiver locks up quickly on clean VSB signals, making it a perfect receiver for my antenna tests. CM has also included direct connections to Vudu and Pandora through their program guide (powered by Rovi!), although Netflix probably would have been a wise addition considering their streaming video market dominance.

I’ve used the DVR+ to record blocks of CBS programs whose schedules are thrown out of whack by late-starting Sunday NFL games that end somewhere in the vicinity of 8 PM EST, and its multi-speed fast-forward/reverse search works quite well, even if it doesn’t have the tactile feedback of a TiVo DVR. Of course, the DVR+ is a LOT cheaper at $250 and there’s no monthly fee for program guide information, as it comes automatically from each TV station.

Given the paucity of conventional set-top boxes for off-air reception, this is one of your better choices and sure beats watching HDTV on your phone, tablet, or computer. Let’s face it; Tom Brady’s Patriots vs. Payton Manning’s Broncos is a lot more compelling on a big screen TV than an iPad!

See you next time I get a pile of antennas…

Editor’s note: Channel Master also offers a 1 TB version of the DVR+ for $399.

Useful Gadgets: Mohu Sky Outdoor TV Antenna

Depending on which media outlets you follow, “cutting the cord” is a fast-growing phenomenon. Or maybe it isn’t. Or maybe it’s a short-term threat to the bottom line of pay TV. Or perhaps it’s a long-term threat.

We do know this: Pay TV subscription rates have increased astronomically in the past ten years. An increasing number of subscribers are bellyaching about paying for channels they don’t watch. Some have even gone so far as to “cut the cord” and drop pay TV channel packages altogether; opting for Internet streaming and in some cases, free over-the-air TV broadcasts.

If you live in a major TV market, chances are there are plenty of free OTA channels you can pull in. Since every television sold since 2006 must include a digital TV tuner for these broadcasts, all you need is some sort of antenna to receive those signals.

And you may be surprised by how many channels there are. If you live in the Los Angeles basin, there are no less than 27 different digital TV broadcast channels carrying over 130 minor (sub) channels of programming! That’s more than I have in my cable TV package, although I’ll grant that I wouldn’t watch many of them.

But at least I don’t have to pay for channels I don’t watch. And that’s the appeal of free OTA TV, combined with on-demand streaming of movies and TV shows from outlets such as Hulu, Amazon, Netflix, and Vudu. All you are paying for is a fast Internet connection.

Here's Mohu's Sky antenna, jury-rigged to a ten-foot mast and ready for testing.

Here’s Mohu’s Sky antenna, jury-rigged to a ten-foot mast and ready for testing.


In the past, I’ve tested a raft of indoor TV antennas from Mohu, Walltenna, Winegard, Antennas Direct, and Northvu. In my most recent test, I also included an indoor test of Mohu’s Sky amplified TV antenna ($169.99, available from Mohu, Amazon, and other online retailers). While it did a pretty good job, this product is intended for true outdoor use and won’t replace a flat, wall-mount antenna.

So, I freed up some time to set up the Sky on my rear deck and really cut it loose. The Sky resembles an “x” dipole, or a crossed dipole antenna. It’s housed in solid plastic and comes with a “J” arm support for and mounting plate for attaching to a roof or eave. The Sky measures 21” x 9” x 1” and is supplied with a 30-foot-long coaxial cable. There’s also an active amplifier inside the Sky, powered by an inline USB-style transformer that mounts at your TV.

You don’t have to use the supplied cable – you can use any cable you want, and I suggest sticking with a decent quality run of RG-6U cable from antenna to TV to keep signal attenuation to a minimum. The phantom power supply will work with really long cable runs (I tried it with 100’ of coax, no problem), and you can also mount the power supply in your basement or attic and split the incoming signal to feed two or more televisions.

Antennas Direct's ClearStream 1 came out of storage for the competition...

Antennas Direct’s ClearStream 1 came out of storage for the competition… did the ClearStream 2, tested on this site a few years ago.

…as did the ClearStream 2, tested on this site a few years ago.


Channel Master's 4221 4-bay colinear UHF antenna uses 60-year-old technology - and still works like a charm.

Channel Master’s 4221 4-bay colinear UHF antenna uses 60-year-old technology – and still works like a charm.

For comparisons, I went into my “aluminum archive” and pulled out a ClearStream 1 (single loop antenna) and ClearStream 2 (dual loop antenna), both sold by Antennas Direct, and a Channel Master 4221 four-bay “x” dipole antenna. To level the playing field, I added an external “off brand” amplifier with the ClearStream and CM antennas. This amplifier has about the same gain figure (15 dB) as the Sky model. (You can’t use the Sky antenna without its amplifier switched on.)


For my tests, I procured a pair of 5’ steel masts from Radio Shack and supported them with a Winegard tripod mount, held in place by cinder blocks. The actual outdoor reception test was simple. I attached each antenna to the top of the 10’ mast and rotated it to aim south-southwest toward Philadelphia (position “A” in the results).

I scanned for active channels using my Hauppauge Aero-M USB DTV tuner stick, and for every channel I detected, I then scanned for Program and System Information Protocol (PSIP data). If I was able to read it and identify the channel, I looked at the actual MPEG transport stream using TS Reader (indicated dropped packets and transmission errors) and finally verified that I had 60 – 90 seconds of clean video and audio with no dropout.

Here's my test rig, with an AVCOM spectrum analyzer and Hauppauge Aero-M connected to my Toshiba latop for reception and measurements.

Here’s my test rig, with an AVCOM spectrum analyzer and Hauppauge Aero-M connected to my Toshiba latop for reception and measurements.

Although this housing is lettered just like the Mohu Bolt amplifier, it's actually a phantom power supply for the Sky's internal preamp.

Although this housing is lettered just like the Mohu Bolt amplifier, it’s actually a phantom power supply for the Sky’s internal preamp.


This process was repeated after I swung the antennas to the north-northwest, towards Allentown, PA. I expected that in some cases, I’d be able to receive stations from both markets regardless of the antenna position. That’s because these antennas are sold as somewhat omnidirectional or “non-directional.” The manufacturer expects you can install the antenna outdoors as high as practical, and you shouldn’t have to worry about its orientation (North? South? West?).

In reality, all of the antennas I tested are somewhat directional, as you’ll see from my tests. So I suggest picking up a small antenna rotor, which is easy to find at Radio Shack and other online stores. Rotors come in real handy if the TV stations in your market have towers scattered all around the city. (Pittsburgh and Atlanta come to mind here.)

I also took a look at the actual 8VSB carrier waveforms using an AVCOM PSA-2500C spectrum analyzer, mostly to see how much multipath “tilt” was present in the signal. I’ve included a few of those screen grabs here to show the relative signal strength of multiple TV transmitters in the UHF band as received by each antenna.

At my location, the pickings on VHF are slim. WPVI broadcasts a towering signal on channel 6 in Roxborough, PA, while WHYY has a potent carrier on channel 12. In Allentown, WBPH is a strong beacon on channel 9. And that’s about it – the rest of the stations are found on the UHF band.

Of that group, several stations usually stand out in my tests. WPHL is very strong on channel 17, as is KYW on channel 26. (I can receive KYW in my basement, and I’m 22 miles away from the transmitter!) WCAU is pretty reliable on channel 34, as is WLVT on channel 39. And WFMZ in Allentown is broadcasting with over one million watts ERP on channel 46, meaning I can usually pull them in with a paper clip.

I should point out here that the vast majority of indoor TV antennas work pretty well at UHF frequencies, but are electrically too small to pull in many high-band VHF channels. They just can’t approach resonance and have gain. The same thing applies to outdoor antennas – a solid performer at UHF frequencies may have little or no gain on high-band VHF channels.

Here's a spectral view of channels 6 through 13, as received through the Sky antenna.

Here’s a spectral view of channels 6 through 13, as received through the Sky antenna.


And here's how channels 6 through 13 look like as received with the ClearStream 1.

And here’s how channels 6 through 13 look like as received with the ClearStream 1. Note that WPVI’s signal on channel 6 (about 85 MHz) is not receivable on the CS-1, but comes in like gangbusters on the Sky (above).

That doesn’t mean you won’t be able to receive any VHF channels. If the signal strength is there, your smaller antenna may couple enough energy anyway to enable reception. But keep in mind that while a quarter-wavelength antenna for UHF reception might only be five inches long, a quarter-wave antenna for pulling in channel 7 needs to be about 16 inches long to achieve resonance.

The moral of the story is that all of the test antennas are physically the right size for pulling in UHF channels. They may not work quite as well for high-band (175 – 216 MHz) VHF channels, and I don’t expect they’d work at all with low-band (54 – 87 MHz) VHF reception. It all depends on the distance from your reception location to the transmitter.


Table 1 shows how all of the antennas fared. In the “A” position, the Sky gave a good accounting of itself, pulling in all three of the Philly and Allentown high-band VHF broadcasts. It also snagged seven of the ten strongest UHF stations coming from both markets. While Antennas Direct’s ClearStream 1 couldn’t find WPVI on channel 6 (that resonance thing, again), it did even better by pulling in the remaining two VHF signals and all ten of the UHF stations.


Table 1 - Results of the outdoor reception tests. Stations received successfully are indicated in green text.

Table 1 – Results of the outdoor reception tests. Stations received successfully are indicated in green text.


Oddly, the ClearStream 2 picked up one VHF channel, but dropped the UHF signal from WYBE-35, giving it a score of 3 VHF and 9 UHF channels. And the venerable Channel Master 4221 four-bay collinear antenna nearly matched it, missing only WYBE and WPVI-6. (Again, this antenna has no gain at lower frequencies.)

Turning the antennas northwest to favor Allentown (position “B”) really quieted things down. The playing field was almost level across all antennas with the Sky locating 2 VHF and 2 UHF stations, the ClearStream 1 digging out one additional UHF station, the Clear Stream 2 adding one more UHF station, and the 4221 spotting one VHF and three UHF stations.

Here's a spectral view of all UHF channels as received with the Sky antenna. Compare it to...

Here’s a spectral view of all UHF channels as received with the Sky antenna. Compare it to…

...all UHF channels received with the ClearStream 1...

…all UHF channels received with the ClearStream 1…

...all UHF channels as received with the ClearStream 2...

…all UHF channels as received with the ClearStream 2…

...and all UHF channels received using the Channel Master 4221.

…and all UHF channels received using the Channel Master 4221. All antennas were in position “A” for these readings.


Mohu’s Sky antenna is a strong performer. It did surprisingly well in my earlier indoor antenna tests, but it’s much happier in free space with plenty of oxygen flowing around it. The antenna does exhibit a directional characteristic, as did the three other antennas in this test. But it was able to handle both VHF and UHF signals with aplomb, although its UHF performance wasn’t quite as good as the ClearStream 1 and 2 loop antennas with external amplifiers.


Mohu Sky Outdoor VHF/UHF TV Antenna

MSRP: $169.99

Sold by Greenwave Scientific


Also available from other online retailers.