Posts Tagged ‘Mohu Leaf Plus’

Useful Gadgets: Indoor DTV Antennas – The Third Time’s The Charm

Earlier this year, I posted a couple of product reviews of indoor digital TV antennas. The first test, posted on April 6, concluded that there isn’t a heck of a lot of difference between a $5 bow tie and a $40 ‘flat’ antenna when it comes to VHF and UHF TV reception.

The second test, posted on May 29, gave one manufacturer a ‘do-over’ as their original product didn’t perform all that well and was judged to be defective. And that test also included a newcomer who didn’t make the original cut. (Believe it or not, both tests grew out of a more impromptu test in my house of a couple of panel antennas!)

Since the Round 2 results were posted, three things transpired. First, I became aware of yet another indoor DTV antenna, called the Clear Cast X1 and sold through Sunday newspaper inserts, magazines, and even on this Web site.

According to Clear Cast, “Advanced patent pending design of the X-1 digital antenna pulls in free over-the-air digital and HDTV broadcasts in your area so you can leave behind cable-only channels & expensive cable & satellite bills. Receive crystal clear digital picture on any digital TV in the house with NO monthly bill, easy install and setup plus NO waiting for the cable guy.” OK, I was intrigued enough to order one (they’re not cheap!)

Secondly, the PR firm that represents Antennas Direct – the company that shipped me a Clear Stream Micron XG for Round 2 testing – inquired why I hadn’t tested the accessory reflector with the antenna. (Simple: As Steve Martin used to say, “I forgot!”)

Finally, the Mohu Leaf Plus that self-destructed in Round 2 had been replaced and was ready for another go. (The amplifier failed, a problem Mohu was aware of and corrected in subsequent production.)

So it was clearly time for one last trek to Mountain Lakes, NJ to put all of the antennas from Round 1 and Round 2 through one more workout. I loaded up my spectrum analyzer, computer, several spools of coax, and a few splitters and headed out to put this test to bed once and for all.

THE TEST

For Rounds 1 and 2, I used the same window as the desk in front of it was unoccupied at the time. This time around, I opted for a slightly different location between two desks so that I wasn’t interfering with everyone’s work. Additionally; since the test position had now shifted by about six feet, I decided to re-test every antenna from Rounds 1 and 2 to be consistent and fair to all.

Here's what the test site looked like.

 

And here's the 'reference' bow tie antenna taped to the window.

I was assisted in my endeavor by John Turner, the owner and president of Turner Engineering and a long-time veteran of the broadcast systems integration world. Using AVCOM’s PSA-2500C spectrum analyzer, we positioned a $4.99 Radio Shack bow tie antenna (no longer available) for best reception of WNJM-51 (now known as “NJTV”) out of Montclair, NJ.

I also connected a Hauppauge Aero-M USB stick DTV received to pull in each station, in tandem with the TS Reader MPEG stream analyzer program to verify reliable reception (i.e. low bit rate errors). Each antenna under test fed the spectrum analyzer and Aero-M through a two-way splitter, and each antenna was placed in exactly the same spot on the east-facing window, using four pieces of masking tape as markers for alignment.

For each test, I scanned for channels using the Aero-M receiver. Next, I scanned each physical TV channel that was received with TS Reader to see how clean that stations’ MPEG stream was. Finally, I captured screen shots of the actual waveforms from each station I received. And if those three steps didn’t prove which antenna works the best, I don’t know what would!

THE RESULTS

For the record, here are all of the test antennas:

 

Radio Shack bow tie ($4.99, no longer offered, but you can find them on eBay)

Clear Cast X1 ($68 plus shipping)

Walltenna ($35 plus shipping)

Mohu Leaf ($38 plus shipping)

Mohu Leaf Plus ($75 plus shipping)*

Winegard FlatWave ($40, free shipping through August 31)

Antennas Direct ClearStream Micron XG ($100 plus shipping)*

* – amplified, or comes with optional amplifier

 

For my tests, I scanned for all New York City and New Jersey DTV stations within range of Turner Engineering. One local station (WMBC-18) was so strong that I essentially discounted it from my test results – it would have come in with a paper clip!

The Clear Cast X1 is definitely NOT worth $70. Let the buyer beware!

 

But other stations weren’t quite as strong. WABC-7 is a good test of high band VHF reception, inasmuch as every antenna in the test is supposed to pull in both VHF and UHF signals. WNJB-8 in the Watchung Hills of New Jersey is another good test of VHF reception.

For UHF signals, I checked out WNYE-24 (atop the Empire State Building), WNBC-28 (also on Empire and usually strong), WFME-29 (in West Orange, NJ), WFUT-30 (on Empire), WCBS-33 (Empire), WWOR-38 (Empire), and WNJM-51 (Montclair, NJ).

I didn’t expect the antennas to have much luck with WABC or WNJB, as they are too small to have much gain at VHF frequencies. The amplified antennas were a different story, though. If you are aggressively marketing indoor TV antennas for ‘all band’ reception, then you’d better deliver!

Table 1 shows how the unamplified antennas compared to each other. Satisfactory reception is indicated by glitch-free video streams for at least one minute and a ‘clean’ reading with TS Reader, while Table 2 shows how the amplified antennas (or amplified variations) compared.

Yes, you can actually attach the Micron XG to glass with masking tape! (The reflector was a tad more difficult to install...)

 

Note that the ClearStream Micron XG was tested three different ways –‘ bare bones’ with no amplifier or reflector in Table 1; with its amplifier switched to 15 dB mode in Table 2, and with the amplifier on and the accessory reflector attached in Table 2.

 

Antenna

WABC-7

WNJB-8

WNYE-24

WNBC-28

WFME-29

WFUT-30

WCBS-33

WWOR-38

WNJB-51

RS Bow Tie

Yes

No

Yes

Yes

Yes

Yes

Yes

No

Yes

CC X1

No

No

Yes

Yes

Yes

Yes

Yes

No

No

Walltenna

Yes

Yes

Yes

Yes

Yes

Yes

Yes

No

Yes

Mohu Leaf

Yes

Yes

Yes

Yes

Yes

Yes

Yes

No

Yes

FlatWave

Yes

Yes

Yes

Yes

Yes

Yes

Yes

No

Yes

Micron XG

No

No

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Table 1 – Unamplified antenna performance

 

Antenna

WABC-7

WNJB-8

WNYE-24

WNBC-28

WFME-29

WFUT-30

WCBS-33

WWOR-38

WNJB-51

Leaf Plus

Yes

Yes

Yes

Yes

Yes

Yes

Yes

No

Yes

Micron XG w/amp

No

No

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Micron XG w/amp and refl.

No

No

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Table 2 – Amplified antenna performance

 

Oddly enough, the Micron XG was the only unamplified antenna to pull in WWOR-38. But it was ‘tone deaf’ when it came to the two high band VHF stations. Neither version of the Mohu Leaf could snag WWOR-38, either.

As for the vaunted Clear Cast X1, it was unresponsive to any VHF channels and couldn’t hear local station WNJM-51. In contrast, the late, lamented Radio Shack bow tie worked exceptionally well on just about every UHF channel.

Bonus reception: WNJU-36, which is a tough signal to pull in at this indoor location, was successfully reeled in by the Micron XG with amplifier and reflector. So was WXTV-40, also pulled in with and without the accessory reflector.

THE CHARTS

I’ve included a few charts to show what the actual DTV received signals looked like on the AVCOM analyzer. You may be surprised to see how small the differences are between each antenna, and you will also note that the reflector didn’t improve reception at all on the Micron XG – in fact, it actually made things worse, probably due to all of the signal reflections and multipath at the test site.

As a reference, the actual signal levels shown are about 12 dB stronger at the displayed resolution bandwidth (300 kHz).

Here's what the RF spectrum looks like from channels 18 to 51, using the bow tie antenna.

 

And here's the same spectral view using the Clear Cast X1...

 

...using the ClearStream Micron XG...

 

...and using the Mohu Leaf (no amplifier).

 

Here's channel 51, the former WNJM, as received on the bow tie...

 

...and here's the same station on the Clear Cast X1. No improvement.

 

Winegard's FlatWave pulled in channel 51 more robustly...

 

...as did the Walltenna.

 

Finally, here are received waveforms for WNJU-36 and WWOR-38, using the ClearStream MIcron XG with the amplifier set to 15 dB, but minus the reflector...

 

...and here's what those same waveforms looked like AFTER I installed the reflector. Reception actually worsened, something I saw on numerous other UHF channels. Indoor DTV reception can be funny that way!

CONCLUSIONS

It’s hard to make much or an argument for spending very much money on an indoor DTV antenna when you see how well the lowly $5 bow tie design performed! This antenna design has been around since the 1950s and is just one of those things that can’t be improved on – unless you build an array of them. (‘X’-shaped colinear UHF antennas perform the same as the bow ties.) It’s just unfortunate that no mainstream electronics retailer sells these anymore. (Hey Radio Shack, are you listening?)

However, it’s easy to make the argument that the Clear Cast X1 is definitely not worth spending $70 on, especially since it was easily outperformed by the far less costly Leaf, Walltenna, and FlatWave antennas. Even the bow tie picked up six more stations than the X1 in my overall tests, two of them on VHF. I don’t know what’s inside the plastic housing, but I’d bet it is nothing more than a simple dipole, bow tie, or loop antenna (Clear Cast’s claims to having a ‘patent pending’ notwithstanding). Keep your wallets in your pockets!

Among the basic flat antennas, I still prefer the Leaf – it’s smaller and more esthetically pleasing than the Walltenna (which still  does a good job, better than the FlatWave) and it’s been a reliable performer everywhere I travel. The Leaf Plus is a bit pricey at $75, but the amplifier – while not as powerful as that on the ClearStream Micron XG – helps pull in marginal stations and doesn’t add much to the form factor.

As for the Micron XG, I had mixed feelings about it. It’s big and somewhat blocky, expensive, and based on my tests, you can’t depend on it for VHF reception in suburban locations, a chore the other ‘flat’ antennas handled without much difficulty. In its favor, the Micron XG did pull in WWOR, something no other antenna could do. (Maybe that outcome was just a fortuitous combination of antenna position and signal level?)

The Micron XG amplifier makes a big improvement, but I’d suggest running it no higher than 15 dB. The 20 dB setting creates too much noise and also degrades weak signals, as observed with the spectrum analyzer. The lower-gain 10 dB setting is also very handy in fringe urban areas where you don’t need tons of signal, but just need to boost the carrier-to-noise ratio (CNR) a bit.

And that reflector? It’s hardly worth bothering with, as it didn’t improve reception on any of the tested channels and in some cases degraded it. Those results were puzzling, because the reflector effectively converts the antenna pattern to something resembling a two-element yagi, which should have more gain as it becomes more directional. Maybe you’d have different results over a line-of-sight (LOS) path, but that’s hard to ensure when trying to grab DTV signals indoors.

In any case, you should be able to get a decent indoor DTV antenna for less than $50. Stay away from the amplified versions unless you live in a fringe urban or outer suburban area, where there are less likely to be out-of-band sources of overload and interference. Always place your antenna near a window and/or closest to the direction of the TV transmitter(s) for best results.

Good luck!

Useful Gadgets: Wall-Mounted DTV Antennas Revisited

Last month, I tested a pile of wall-mounted indoor digital TV antennas to see if they really work as advertised.  Two of them (Mohu’s Leaf and the Walltenna) performed decently, while the amplified LeafPlus was a clear winner.

On the other hand, Winegard’s FlatWave was a disappointment, as it didn’t perform any better than a $4.00 Radio Shack bow tie antenna. That result led to a request from Winegard to return the review sample and see if it was defective.

It was, according to Winegard’s National Sales Manager, Grant Whipple. The culprit was (according to their email) “…a screw that was stripping and then causing a loss of contact between our circuit board and the antenna element itself.” Apparently this was an early production run issue.

Fair enough. Grant soon had a replacement back to me. Meanwhile, Scott Kolbe, who handles PR for Antennas Direct, sensed an opportunity and sent me a sample of their Micron XG indoor amplified TV antenna to test drive. The Micron XG isn’t a flexible, thin wall-mount design, but it is an indoor antenna and I decided to test it alongside the Winegard.

The Micron XG 'stuck' to the window. I never expected this to work -- but it did.

 

Here's what the Clearstream Micron XG amplifier looks like up close.

The tests, as before, were conducted at the offices of Turner Engineering in Mountain Lakes, NJ. I stopped by there after some RF interference testing in midtown New York City the Friday before Memorial Day weekend, and John Turner and I had the run of the place – everyone had gone home for the weekend.

To make things more interesting, I brought along the Mohu Leaf Plus, the original RS bow tie antenna, and my spectrum analyzer and digital camera.

THE TEST

John and I followed the same test procedure as we did in April. Each antenna was taped to the window with masking tape in the same position. A channel scan was performed with a DTV receiver (this time, it was Samsung’s DTB-H260F) and we verified dropout-free reception for 1 minute on each channel to qualify it as “received.” I also recorded the transport stream from each channel to check for bit error rates (BER) and recorded screen grabs of the actual waveforms for comparison among antennas.

Things started off again with the bow tie, which pulled in (unamplified) seven stations, all operating on UHF channels. The strongest local stations were WMBC-18 in Upper Montclair, NJ, and WNJM-51; also on the same tower. But the bow tie also snagged WNBC-28, WFUT-30, WPXN-31, and WXTV-40 from the Empire State Building, along with WFME-29 from West Orange, NJ. All seven stations were received reliably on the Samsung tuner.

Next up was the replacement Winegard FlatWave. After a channel scan, it also snagged seven stations including WNJB-8 (high band VHF!), WMBC-18, WNBC-28, WCBS-33, WXTV-40, and the 2nd minor channel from WNYW-44 (virtual channel 5-2). Of course, WNJM-51 also came in with no sweat.

 

Here's how WMBC-18 looked on the Winegard FlatWave antenna...

 

...and here's how the same station looked on the $4 Radio Shack bow tie antenna.

 

In essence, it was a draw between the $40 FlatWave and $4 bow tie. The FlatWave did pull in a high band VHF station, something the bow tie could not do reliably. But the bow tie snagged three UHF stations that the Flat Wave couldn’t reel in, one of which (WFME-29) was very strong on other antennas.

Just for kicks, I hooked up the original Mohu Leaf and let it do its thing. The result was nine reliable UHF channels, adding WNJU-36 and WWOR-38 to the previous lists. Catastrophe struck with the Leaf Plus, though – even though its power indicator LED was lit, absolutely ZERO signal passed through to the analyzer. It was cooked!

 

Here's what the UHF TV spectrum looks like with the amplified Micron XG...

 

...and here's how the same block of channels appeared with the amplified Mohu Leaf (not the Mohu Plus).

 

By itself, the Clear Stream Micron XG reached out and grabbed six UHF stations – WMBC-18, WNBC-28, WFME-29, WCBS-33, WXTV-40, and WNYW-44’s ’5-2’ service. WNJM-51 finished off the list. Not bad, but hardly an improvement over the bow tie. Adding the inline preamp netted three more UHF stations – WFUT-30, WPXN-31, and WCBS-33, putting the Micron XG on a par with Mohu’s basic Leaf. One caution – the in-line amplifier lets you kick in 5, 10, 15, or 20 dB of signal boost, but you need to use it sparingly – otherwise, you’ll ‘swamp’ your TV and create a lot of noise across the band.

Since the Micron XG preamp is a standalone product and works with its own power supply, we decided to have some fun and try it with the rest of the antennas. Hooked up to the bow tie, it delivered WNJB’s channel 8 beacon, plus WNYW-44’s ‘5-2’ service (whatever happened to 5-1?) and WWOR-38. Cool!

The FlatWave also benefited from additional amplification, pulling in ten different stations (WNYE-24 was the newcomer). But so did the Mohu Leaf, which snatched eleven different DTV stations, one of which was WNJB on highband VHF channel 8.  The table below summarizes the results for what are the nine strongest DTV station signals that could be received during the test. Each station’s call sign is followed by its physical channel.

 

THE RESULTS

A few solid conclusions came out of this re-test. First, the Mohu Leaf is still a formidable contender, amplified or otherwise.  Even though it doesn’t have much gain at highband VHF frequencies (channels 7-13), it also managed to pull in channel 8 with a boost from the Micron XG amplifier. (I’m still checking on what happened to the Leaf Plus.)

Second, I didn’t see much of a difference between the defective FlatWave and its replacement. True; the 2nd model fared somewhat better than its predecessor. But in terms of total stations, it didn’t do any better than the humble bow tie – it just substituted three different stations.

The Micron XG – which we actually wound up taping to the window for the test, using LOTs of masking tape – was a pretty weak performer without its accessory amplifier. However; with the amplifier, it was able to haul in three additional stations. But the Leaf did even better when amplified, capturing a test-high 11 stations reliably, one more than the FlatWave when it had a dance with the external amplifier.

Compiling the ‘yes’ and ‘no’ results into won-lost records, the Mohu Leaf finished in first place at 7-2 competing in the ‘no amplifier’ class, with a three-way tie at 6-3. In the ‘amplified’ division, the Leaf and FlatWave tied with 8-1 records, just head of the 7-2 Micron XG. (I didn’t list the amplified bow tie here, but it finished in 3rd place with a 6-3 log.)

How about performance vs. value? The Leaf is currently advertised on the Mohu Web site for $36, while the FlatWave is ticketed at $40. The ClearStream Micron XG will set you back $100 (the unamplified Micron A version is $60), while the humble bow tie is (gasp!) no longer listed on the Radio Shack Web site. (I guess it makes no sense to sell a $4 antenna when you can push a $20 Terk version that looks cooler.)

CONCLUSION

You don’t need to spend a ton of money to get decent DTV reception. In fact, you should be in good shape for no more than $40, based on my tests. If signal levels are really low, the amplified models will make a difference. Based on my tests, I’d suggest sticking with the Leaf Plus, as it is $25 cheaper than the Micron XG – and a lot easier to mount to a variety of surfaces, given how light and flexible it is.

And isn’t it amazing just how well a bare-bones antenna works? Higher cost doesn’t always equal higher performance. Caveat Emptor!

 

Useful Gadgets: Wall-Mounted Indoor DTV Antennas

A few months back, I ran a test of several indoor DTV antennas that you can mount on the wall, or on a window. Specifically, I looked at Mohu’s Leaf antenna and the Walltenna, and compared them to a baseline UHF table-top antenna and a $12 Radio Shack set of rabbit ears and a UHF loop.

 

Since then, I’ve received a few more samples to test against the Mohu and Walltenna. Mohu shipped me the amplified version of their Leaf (Leaf Plus, $74.99) while Winegard dropped off a sample of their FlatWave indoor antenna (FL5000, $39.99).

 

Well, nobody enjoys a good antenna test more than I do – except perhaps John Turner of Turner Engineering in Mountain Lakes, NJ, who offered to let me use his facility for these tests. So, I piled all of the flat antennas used in the December tests plus a Kowatec UHF panel antenna, a $3.99 Radio Shack bowtie, an AVCOM PSA-2500 spectrum analyzer, and a pile of coax jumpers into my car and headed north one fine day in late March.

 

At the test site, I was directed to use a large office window that faced east. A nearby desk provided a home base for the PSA-2500C and my laptop computer, which would simultaneously mirror the spectrum analyzer screen while running a Hauppauge Aero-M ATSC/MH USB stick receiver and the TS Reader MPEG stream analyzer program.

Here's the office window I used for the tests, with theKowatec panel antenna connected.

Here's the logging station, running WinTV7 and TS Reader for each antenna.

 

The methodology was to tape each antenna into the same position, connect 20’ of coax through a two-way splitter, and scan for channels while looking at each received DTV waveform. The TS Reader program would then confirm whether I was actually receiving a signal reliably, by providing me a read-out of the MPEG transport stream and the bit error rates (BER).

 

Speaking in plain English, this test was conducted as fairly as possible, favoring no antenna. I made no effort to try and ‘peak’ antennas for more reliable reception – I just taped them up and scanned away, just as the average consumer would do. Next; for every DTV station I supposedly ‘received’ on the Aero-M, I checked the quality of their signal before giving them a thumbs-up.

 

THE TESTS

 

Simple enough! Once each antenna was mounted to the wall (the Kowatec was attached to a tripod and placed in the same position as the other antennas), I performed a channel scan with the Aero-M, looking for both ATSC and ATSC MH (mobile) DTV signals.

 

After each scan was completed, I looked at each channel that was detected to see if a signal was actually present. (Sometimes ATSC receivers grab just enough PSIP data from an othwerwise weak signal to ‘capture’ it, which is why you have to verify reception.) If the signal played back reliably for several minutes with no drop-outs, I gave it a thumbs-up and moved on to the next detected channel.

For a measly $4, this bow tie antenna gave a very good account of itself.

Here's the Mohu Leaf doing its thing.

The Walltenna isn't easy to photograph against trees!

Winegard's FlatWave resembles the Leaf in appearance, but not in performance.

Here's the Leaf Plus, powered up and snatching signals.

 

After this process was completed, I then used TS Reader to see just how reliably each signal was coming through. TS Reader shows the accumulated number of dropped bits (BER) as you watch the program. The lower the BER, the more reliable the signal.

After compiling a list of stations received with all antennas, I then picked the seven that showed up repeatedly, whether received reliably or not. They were WABC (physical RF channel 7) from New York City, WNJB (physical channel ‘8’) in the Somerset hills in central New Jersey, WMBC (physical channel 18 from Montclair, NJ), WNBC (physical channel 28) from New York City, WWOR (physical channel 38) from New York City, WXTV (physical channel 40) from New York City, and WNJM (physical channel 51), also from Montclair, NJ.

 

According to the TVFool Web site, WMBC and WNJM are just 11.7 miles away from the Turner offices and are both ‘line of sight’ (LOS) paths, while WFME-29 (which didn’t come in reliably on any antenna save one) is a hair closer at 11.4 miles, LOS. WNJB sits 19.4 miles over a LOS path, while WWOR-38 in New York is 24.9 miles and also LOS.

 

WABC-7 and WXTV-40 were both shown as 1-Edge paths from the Empire State Building and also 24.9 miles away, while WNBC-28 was listed as a 2-Edge path (lots of multipath) from the same distance. So I had a nice mix of strong, ‘easy’ signals to go with some weaker, ‘tough’ signals.

 

Table 1 shows the results. A ‘yes’ indication means that the station was received without drop out for at least two minutes AND had a very low or almost zero bit error rate, as verified by TS Reader. A ‘no’ indication means either the station was not received at all, or was detected by PSIP but had too many dropouts to be reliable.

Table 1

 

Not surprisingly, the Kowatec antenna couldn’t pull in either high-band VHF stations 7 or 8. That’s because of simple physics: It has no gain at those frequencies, and its antenna array is too small to be of any use with channels 7 through 13.

 

I didn’t expect much from the Radio Shack bow tie, but it did OK by grabbing channels 8, 18, and 51. Not surprisingly, these are the three strongest signals at the Turner office location, so every other antenna should have pulled them in (which they did).

 

The Mohu Leaf gave a decent accounting of itself, grabbing channels 8, 18, 28 (one of the strongest UHF stations in New York City), 40 (also a powerful signal), and 51. The Walltenna equaled that performance with the same channels – no advantage here.

Here's the strongest local signal, WMBC-18, as received with the Radio Shack bow tie.

The Winegard FlatWave didn't pull in WMBC-18 any better than the bow tie.

Ironically, the now-discontinued Kowatec did a better job with channel 18 than any other non-powered antenna!

 

The FlatWave was a big disappointment, faring no better than the $3.99 bow tie – and it costs ten times as much! Most of the antennas in this test use variations on collinear antenna arrays, but aren’t electrically long enough to have any gain on channels 2-6 and 7-13. But the FlatWave didn’t even have that much gain at UHF frequencies.

 

I saved the Leaf Plus for last. Comparing an amplified antenna to non-amplified versions isn’t a fair test, and as expected, the Leaf Plus pulled in all of the listed stations reliably, except for WWOR-38.

 

However, it added WFME-29 (West Orange, NJ), WFUT-30 (Telefutura from New York), ION-30 (also New York), WCBS-33 (New York), and WNJU-36 (Telemundo, New York) to the list of ‘thumbs up’ stations.

 

Note that a few of these signals are listed as 2-Edge paths with much weaker signal levels on TVFool.com. So this antenna does perform very well, although a bit pricey at $75.

 

CONCLUSIONS

 

Reliable digital TV reception is all about having enough signal presented to the receiver so it can do its job. That also means high enough carrier-to-noise ratio (CNR) for the adaptive equalizer circuits to smooth out echoes and other signal reflections caused by multipath.

 

In general, any late-model TV built in the last four years has good-enough adaptive equalizer circuits to accomplish this task if it is presented with enough signal. For people who have problematic over-the-air DTV reception, low signal levels are usually the culprit. I’d suggest using the non-powered antennas if you live 15 miles or less from a DTV transmitter, and switching to an amplified antenna at greater distances. (Once you get much past 25 – 30 miles, you should really put up an outside antenna for best results.)

 

The Mohu Leaf and Walltenna work quite well for close-in DTV reception, while the Leaf Plus makes a big difference at longer distances. The FlatWave is a disappointment – save your money and go with the Leaf or Walltenna instead. Or, try a simple bow-tie or even Radio Shack’s 15-1882 VHF rabbit ears / UHF loop combo instead – for $12, you can hardly go wrong.

 

Ever wonder how much difference an RF amplifier makes? Here's a view of channels 18 through 51 at the test location, using the Mohu Leaf...

 

...and here's the same spectral view, this time using the Mohu Leaf Plus for reception.