It’s been a while since I reviewed my last batch of TV antennas, but the topic is worth revisiting with the ongoing spectrum auction and an apparent increase in cord-cutting as people ditch more costly pay TV packages for free, off-air reception of broadcast TV channels.
Plus, in case you hadn’t noticed, the Olympics are under way and NBC has saturated the airwaves with coverage across a multitude of channels, including Telemundo. That means you may be able to watch events on two broadcast channels in addition to streaming channels.
A couple of weeks ago, the folks at Antennas Direct sent me one of their ClearStream Eclipse antennas. ($59.99, various retailers) It’s shaped like a big loop, is flexible, and has a black finish on one side and white on the other. Plus, the surface is known as SureGrip and will stick to just about any surface, over and over again.
Like other ClearStream antennas I’ve tested, the loop appears to be optimized for UHF reception. And that could be problematic, since the FCC may wind up taking away at least 10 (if not more) UHF channels after the spectrum auction, assuming the bids are successful.
That, in turn, may force more than a few TV stations back onto high-band VHF and (horrors!) even low-band VHF channels if they want to stay on the air. And digital TVs need much larger antennas to pick up broadcasts on channels 2 through 6, unless you’re located fairly close to the TV transmitter and the signal levels are very high.
ClearStream has also included an inline amplifier to boost signal levels. Technically, it qualifies as an antenna-mounted amplifier, although you can place it anywhere ahead of the TV or set-top box receiver. This amplifier does make a big difference, as you’ll see in a moment.
For the purposes of this review, I went into my lab and fished out my trusty Radio Shack bow tie antenna (not available anymore, but it cost all of $4 back in the day) and also a spare Mohu Leaf antenna; both for comparison. I also grabbed an “anonymous” inline, 15 dB VHF/UHF preamplifier that would normally mount on a mast but was quite happy sitting on the floor.
I also set up a crude antenna support – a shipping box from a well-known retailer of just about anything electronic in New York City. I taped each antenna to the box (which was standing on its end) and placed the box atop a perch my cats use to look out the window.
This box was positioned near the window in an upstairs room, facing in the general direction of the Philadelphia DTV antenna farm. I operated much as the average TV viewer would – I didn’t know exactly where to aim the antennas, but used consumer DTV sites to use dead reckoning and hoped for the best. 20’ of RG-59/U cable ran from each teat antenna back to a two-way splitter, feeding a spectrum analyzer and my Hauppauge Aero-M USB stick DTV receiver.
I connected each antenna and scanned for VHF and UHF channels three times – once without any amplification, once with my ‘anonymous’ amp, and once with the ClearStream amplifier. I captured spectral waveforms for selected channels on the analyzer and also ran a quick MPEG stream analysis using TS Reader.
The stations I looked for were in order WPVI (ABC, channel 6), WBPH (IND, channel 9), WHYY (PBS, channel 12), WPHL (My, channel 17), KYW (CBS, channel 26), WUVP (Univision, channel 29), WPSG (CW, channel 32), WCAU (NBC, channel 34), WYBE (IND, channel 35), WTXF (FIX, channel 42), and WFMZ (IND, channel 46). Channels 9 and 46 originate from Allentown, PA; the rest come from the Roxborough section of Philadelphia, about 20+ miles from here over an obstructed path.
After compiling that data, I had a pretty good idea of how each antenna worked. The results can be seen in table 1, and once again, it’s pretty amazing how functional the bow tie is. Not a great performer without an amplifier, but with the ‘anonymous’ amplifier it grabbed 9 of the 11 stations, including WPVI on channel 6. It performed even better with the Eclipse amplifier, pulling in 10 of 11 stations. (WTXF-42 reception was erratic.)
Mohu’s time-tested Leaf was next. As a solo act, it sniffed out 5 of 11 stations and also found WPVI without amplification, so its low-band VHF performance was good. Adding the ‘anonymous’ amplifier improved the score to 8 out of 11, and switching to the Eclipse amplifier added one more station. This was the only antenna to pull in WTXF-42 reliably, using amplification.
Finally, it was time for the Eclipse to take its turn. Riding bareback, the Eclipse tied the Leaf and snared 5 of 11 stations – but not WPVI-6. Adding in the ‘anonymous’ amplifier improved its score to 9 up and 2 down, while switching to the Eclipse amplifier resulted in one less receivable station (WPSG-32, which is a bear to pull in at any time). But I could not receive WPVI in any of the three modes.
And the spectrum analyzer grabs show why. WPVI’s 8VSB waveform is at least 20 dB above the noise floor with either amplifier, and actually closer to 32 dB C/N when you add the correction factor for this resolution bandwidth. Using the Eclipse, channel 6 measures only 10 db C/N (22 dB with correction factor) using the ‘anonymous’ amplifier and barely 14 dB C/N (26 dB with correction) using the Eclipse amplifier.
That’s just not strong enough for reliable reception, especially when you see the 6 dB notch in WPVI’s carrier from multipath. There’s also about 6 dB of multipath tilt through the Leaf, but the overall signal is much stronger and well within the range that can be corrected by adaptive equalization. And the cleanest signal was seen with the bow tie – not as strong as the leaf, but minimal tilt and notching and easy for the TV to demodulate.
Based on my measurements, the inline Eclipse amplifier has somewhere between 18 and 20 dB of signal gain, and lo and behold, that’s what it says in the dual-side instruction sheet. No specification was given for noise figure, but it appears to be about 2 dB in the UHF TV band, based on my noise floor measurements (-88 without, -86 with).
The ClearStream Eclipse is certainly small and can go just about anywhere – and it’s not likely you’ll damage it, given how flexible the housing is. This loop antenna is a decent performer with UHF and high-band VHF signals, but just doesn’t have enough gain for reliable low-band VHF TV reception.
That may not be a problem if you don’t have any low-band V’s in your area, but you should check TVFool.com in any case as we’re starting to see lots of low-power repeaters and independent stations lighting up on channels 2 through 6 all across the country. One of those stations could be your ticket to watching a TV network you wouldn’t be able to otherwise.
The Mohu Leaf did a better job with channel 6, but was no better in overall station count unamplified. And connected to an amplifier, the bow tie gave both the Leaf and Eclipse a run for their money. With the Eclipse amplifier, it was a dead heat between the Leaf and bow tie (10-1 scores), with the Leaf locking in WTXF-42 and the bow tie securing the difficult WPSG-32.
Posted by Pete Putman, August 11, 2016 3:41 PM
About Pete PutmanPeter Putman is the president of ROAM Consulting L.L.C. His company provides training, marketing communications, and product testing/development services to manufacturers, dealers, and end-users of displays, display interfaces, and related products.
Pete edits and publishes HDTVexpert.com, a Web blog focused on digital TV, HDTV, and display technologies. He is also a columnist for Pro AV magazine, the leading trade publication for commercial AV systems integrators.