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Ultra, if it is not on the Antenna Chart, do not buy it. That way you will always get the best antenna for your needs as tested and proven by our years of ongoing research. You'll also find that the Antenna Chart models are often not much more different in cost than the crappy ones out there.

If you are hell bent on buying a Volfe HD-007, take lots of photos and measurements of it on the ground before putting it up so that we can subject it to our in-depth analysis in the Antenna Research & Development sub-forum.
 

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The price I gave you or the price you found on your own? I found this on Kijiji, see?
I've come across a few of these high gain antennas that are priced to disappoint, but from where does the disappointment come? Is the gain overstated? What's left after that? Material durability? Esthetic value?
Again, I have no experience with this brand. But from what I could see, it's being sold off "as is" on sites like Factory Direct for $29 as a "final clearance" item. They're basically giving them away and don't appear to be continuing to sell this brand. And you have no warranty.

WIth some other clone brands, we've seen poor design and construction and vastly exaggerated performance claims. One discount company even plagiarized this forum.

For myself, I'd rather spend a little more for a reputable brand such as Antennas Direct that has a life time warranty and excellent customer service. Who wants to climb a roof or tower to install an antenna that is likely to disappoint or fail in short order?
 

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Yes, the WallTenna is TOO SMALL to provide OPTIMUM performance in the NEW UHF Band (Ch14-51) and is also TOO SMALL to provide any more than minimal performance, with high SWR in the Hi-VHF Band. But the Quick&Easy Modifications I modeled bring it up to the performance of an M2 and within 1-2 dB of the performance of truly OPTIMIZED, FULL-SIZE Antennas, such as the H2 and the fol. RLH2 (two versions) of 2-Bay Bowties with Hi-VHF Resonator Loops:
http://imageevent.com/holl_ands/loops/hu2baylooprlh212x10norefl
http://imageevent.com/holl_ands/loops/uhfrlh2baybowtierectloopnorefl
And [20"Hx22"W] H2 with poor Hi-VHF SWR (WITHOUT the Hi-VHF Resonator Loop):
http://imageevent.com/holl_ands/multibay/uhf2bays/uhfh22baybowtienoreflector

But Walltenna is probably NO WORSE than most (all???) of the OTHER Antennas on the market that are TOO SMALL, e.g. Mohu Leaf, Winegard Flatwave and many other "Flat Panel" type Antennas. 4nec2 Model for Flatwave revealed UHF Raw Gain = 3-4 dBi with Good SWR and Hi-VHF Raw Gain = 2.5-2.8 dBi (with Excessive SWR)....about as "good" as a mis-tuned VHF-Rabbit-Ears+UHF-Loop....and significantly lower UHF Gain than Unmodified WallTenna:
http://imageevent.com/holl_ands/multibay/uhf2bays/hivhfuhf2baywalltennaenhancements



Adding an Optimized set of Reflector Rods increases Gain by about 3 dB:

 

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Volfe 4 bay HD-007

From Post #218:
I can't find anything about this antenna. What are its characteristics and quality? I found a guy offering 25$ for it.
Only worth about $10 used.
I have a pair of these vertically stacked and co-phased and they worked well enough to spur me on to purchasing better quality a few years later.

I consider these to be "gateway" antennas in that people who are just a bit curious about OTA reception can buy one at low cost, get some local stations that look great, and then realize that higher quality antennas will give them better long term reception and more stations.

Many folks are frugal so a low cost clone can often be that initial "foot in the door" that results in the self assurance that spending more on quality stuff is the right path for them.
Dropping a ten spot isn't a huge deal for a curious fence sitter but spending 15 times that might be just past the point of "I'll get around to that sometime".
 

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"Focus" brand OTA antennas?

I've been seeing these popping up and the local antenna retailer says they're actually okay. He also refuses to sell Digicrap which gives him a shred of credibility. They look alright in the store. Wondering if anyone actually has tried them and has something to say about it? I searched all over the forum and didn't see them mentioned at all.

PS: There's a DB4e hanging on the side of my house, I just installed a Ch4221HD at the girlfriend's house and somewhere out there is the scrap from my first Digicrap antenna that I chucked because it sucked. I have a bit of experience in what's good and what's not.
 

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Focus Antennas are clones

Thanks for the tip, Wildfire. They probably are "okay" and not great.

Focus Antennas are clones. That is not a good sign. Here is their web site: Outdoor Antennas. They are one of the OTA gear sellers on Matheson in Mississauga, ON.

If the person running Focus Antennas really, truly wants to have credibility around here they will tell us exactly which Chinese source those antennas come from so that we can subject the designs to proper 4nec2 analysis as we have done over the years with a wide variety of commercial OTA antennas.
 

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Hello

for the Focus Antennas we have coperation with one of the european companies we are dealing with from last 8 years now..
we will ask them do send us the reports for there testing and also would like to see if we are still treated diffrently..
as we have also designed our latest pre amp and we have them in 2 models.. one with built in LTE Filter
Thanks
 

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They all look like KLONES of A-D products....except for the one that looks like a Silver-Sensor 7-El LPDA plus a Swept Forward Dipole for Hi-VHF...WAY overpriced, esp. considering it doesn't include a Preamp. It if wasn't so expensive it would be a much needed replacement for the discontinued UN-Amplified HDTVa.

BTW: LTE Band in Europe (and elsewhere in world) starts at 800 MHz, whereas North America starts at 700 MHz.....so a Euro Spec Preamp with LTE Filter does NOTHING to suppress OUR LTE Band....
 

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Hello focusantennas,

I think customers must have told you that we don't recommend your OTA products here. Are you looking at improving your line of OTA gear to make it competitive with leading brands? We base our opinions on testing and verification via expert computer analysis and real world experience from industry professionals, advanced hobbyists, and our Digital Home members all across Canada and the USA. Above all, we are fair, and we place the interest of consumers first.

As holl_ands mentions, antennas following European bands are not optimized for North America.
 

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Well...that isn't exactly what I said....I only commented re LTE Band differences...but since you brought it up....Optimizing an Antenna Design specifically for our 470-698 MHz Band (which will be shrinking yet again in the near future) allows for MORE GAIN on ALL Channels, esp. the Lower Channels where most Yagi Type Antennas lose a lot of Gain. DIY examples include various Grey-Hovermans, Mclapps's M4 4-Bay and my H2, H3, FF4 and FF6 Multi-Bay Bowtie and various other Antennas (e.g. Hourglass-Loop, QuadTrap-Loop, LPDAs, Yagis, et.al.)....with 4nec2 Analysis Results found at the link in my signature line below....

OTOH: There ARE some Euro Antenna Designs that were specifically designed to cover 698 MHz....and THEN rolls off....some are found here:
http://www.aerialsandtv.com/aerials.html
BTW: Check out some of the "Group B" Antennas, bearing in mind that 698 MHz falls within Euro Ch49:
http://www.aerialsandtv.com/gaincurves.html#Bgroups
 

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We are willing to improve our quality and the antennas we brought mainly we have them designed for the north american market. and first we try the antenna at our dealers and testers and then if things goes smooth then we bring them in bulk.
and also we do offer money back warranty for the antennas for 30 days. no question asked.

as for as the preamps with LTE Filter the the details r following..

UHF/VHF preamplifier
Frequency: 47-700MHz
Trap: FM(88-108MHz)
Gain: 30±2dB, 18±2dB

and for the LTE Filter is following..

Pass Band: 5-700 MHz
Filter Band 730-1000 MHz
..
 

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Is the 30 dB Gain for VHF or UHF Band??? That is VERY HIGH and would likely cause Overload/Desensitization problems for most users. Note that Overload Specs (e.g. DIN45004 or equivalent) are missing....

How much loss at 698 MHz??? How much Loss beginning at 730 MHz???

Focus Antennas APPEAR to be designed for OLD UHF Band (just like their OLD A-D and C-M counterparts), rather than being Re-Optimized for 470-698 MHz. How about some SPECS to back up your claim that they are designed for North American Market???
 

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No Noise Figure or Overload Specs....or Tests. Looking at the Circuit Board, is looks like the GAIN SWITCH simply inserts a 12 dB Attenuator PRIOR to the Amplifier....which would greatly degrade Noise Figure when Lower Gain is enabled. [I would have chosen 6 dB, rather than 12 dB Attenuator....better yet, use Variable Gain, Dual Gate MOSFET.]

FYI: To me it appears that INPUT is on the LEFT, goes through a series of VHF and UHF Full Band Filters to the FM FILTER SWITCH (FM Filter Circuitry just below) and then to the GAIN SWITCH, which Enables or Jumpers Across a Resistor. The signal then goes through an Amplifier (54-700 MHz, NOT separate VHF and UHF Amps) and hence to the OUTPUT on the RIGHT. DC Power from that same connector travels DOWN thru an Inductance Coil to an on-board Voltage Regulator chip and then a series of isolation/voltage reduction Resistors that feed the Amplifier directly above. Note that two of these feeds go through Coils to prevent shorting out the RF signals.

From the Spectrum Analyzer Displays, there is a GAIN SWITCH that selects either 18 dB or 30 dB (consistent with the +/- 2 dB Spec) for BOTH VHF and UHF....that would be VERY useful to prevent Overload. Note that the Preamp does NOT use separate VHF and UHF Sections...which would ALSO have helped to prevent Overload of UHF signals from the more problematic VHF/FM signals.

There ALSO is an FM TRAP SWITCH, which enables an FM Band Filter with about 20 dB Loss (22 dB on 108 MHz Marker Freq), but they have chosen to PASS Ch6, so there is only about 5-6 dB Loss on 88 MHz. Unfortunately not enough resolution to actually SEE the Frequency Response across the FM Band....

LTE Filter is indeed intended for North American TV Band, with only about 1 dB Loss on 700 MHz and about 28 dB Attenuation on 750 MHz with either Gain Selection.
 

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any recommendation what should be the ideal LTE filter or this should do the job ?
we did thought to have a just a push button for changing the gain which can be done from outside but then dropped the idea.
 

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Noise figure is : ≤3dB
Max output level : 118dbuv

and when i check with our technician in china regarding the rejection should start from 695 so there response is that then pass band should be 5-660MHz and which channels then be missing if we do that ?
 
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