The Official AVS Antenna and Related Hardware Topic! - Page 599 - AVS Forum | Home Theater Discussions And Reviews
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post #17941 of 18323 Old 11-25-2019, 12:55 PM
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Quote:
Originally Posted by rabbit73 View Post
Your signals are quite strong. I consider mounting outside a last resort, and suggest you try different antenna locations inside with the antenna aimed at 65 degrees True. A strict interpretation of the NEC would require that an outdoor antenna be grounded, which would add a complication. The local AHJ (Authority Having Jurisdiction), who is usually the electrical inspector, has the final say. His interpretation becomes the law that is binding on you and the local electricians.

My signals are about the same strength, and I have satisfactory reception indoors, on the ground floor, without a preamp. Try the easy way first. If you find that satisfactory reception is not possible, even with an antenna with more gain (Winegard HD7694P is a step up) and a preamp in the attic, then you have a good case if the FCC has to make a final decision in the event of a dispute.

A preamp or a distribution amp can compensate for long coax runs or multiple TVs as SFischer1 stated above. What counts is how strong the signal is coming out of the antenna terminals which is determined by the antenna location and antenna gain. Try downstairs first. Then try an upper floor and finally the attic with a temporary run of coax. Don't drill any holes yet. Then you will know where the antenna needs to be located. A preamp shouldn't be necessary; a distribution amp might be needed if there are many splits. Either can be powered remotely through the coax with a power inserter.


Thanks. So you’d recommend one of the indoor solutions SFischer1 recommended as well for a starting point?


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post #17942 of 18323 Old 11-25-2019, 01:11 PM
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Originally Posted by Superman07 View Post
Thanks. So you’d recommend one of the indoor solutions SFischer1 recommended as well for a starting point?
SFischer1 didn't recommend an indoor solution as a starting point; he recommended starting outside. I recommended starting inside; starting the easy way first gives you information and experience to go further if necessary to play the role of David (as in David vs Goliath).

Reference his quote:

Quote:
Originally Posted by SFischer1 View Post
Are you saying you are under the control of a HOA (Home Owners Association).

I am but as the FCC allows you one outdoor antenna I suggest you talk to your board of governors. They likely are aware of the law and have a method for you to have an outdoor antenna. Mine is in a good position and is attached to part of the building that I do not own.

https://www.avsforum.com/photopost/s...hp?cat=2165469

The attachment was made to the fascia so that no roof damage (Water leaks from my A/C will cost me $200,000.00) can happen.

The main concern will be the number of splitters, that can be overcome by an amp or a distribution amplifier, mine is a eight way.

SHF

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post #17943 of 18323 Old 11-26-2019, 01:33 AM
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Quote:
Originally Posted by Superman07 View Post
Thanks. So you’d recommend one of the indoor solutions SFischer1 recommended as well for a starting point?


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Start first with an indoor or attic antenna. Perhaps Clearstream 4V or 4MAX UHF loop antenna with VHF dipole. Add a Winegard LNA200 preamp at the antenna. If you have a long cable run or multiple splits, then perhaps a Channel Master distribution amp further down the line. The DC signals are strong and should be no issue. If you want to pull in Baltimore, it may require a separate higher gain antenna, such as Winegard 7694.

Also one other choice for compact flat panel UHF antenna with VHF dipole and indoor stand, consider Antop 800SBS specific model with built in preamp. Works very well. Best price may be HSN with NEW20 promo code, but also on Amazon. The Antop 800SBS is the better version, as the 400BV does not have a built in preamp but rather an inline amp instead.
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post #17944 of 18323 Old 11-27-2019, 10:00 PM
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Quote:
Originally Posted by tylerSC View Post
Start first with an indoor...
I have a FM antenna pinned to the east west wall.

Depending on where I am in the room, the music is clear or distorted from a transmitter to the east. I listen only to one station. (KDFC)

-----------------------------------

Beware that any indoor antenna may be affected by items in the room including you.

Some stations may not be affected, but you can bet that the one you wish to receive will be.

-----------------------------------

Attic antennas may be problematic depending on the metal up there and the placement of the antenna.

I had a four bay bow tie antenna with an amp on a rotor.

Before the NTSC transmitters were turned off and the ATSC transmitters were much lower on Sutro tower, in the winter I could rotate the antenna 365 degrees and not get a acceptable signal from the station I wished the most. The best direction was 180 degrees away from the transmitter.

That and the VHF-Hi/Lo antenna still are in my attic, silenced by the new metal roof.

My outdoor antenna is preforming just fine for all the stations I wish to receive, well until the repack started.

My desktop antenna is now in a room that I seldom am in and is receiving the problematic station's translator just fine.

If you are not going to watch much TV and are willing to move the indoor antenna around to find a sweet spot then go with an indoor antenna.

SHF
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post #17945 of 18323 Old 11-28-2019, 04:39 AM
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Three Different Indoor Antenna Locations for the Same Channel

Quote:
Originally Posted by SFischer1 View Post
Beware that any indoor antenna may be affected by items in the room including you.

Some stations may not be affected, but you can bet that the one you wish to receive will be.

-----------------------------------

If you are not going to watch much TV and are willing to move the indoor antenna around to find a sweet spot then go with an indoor antenna.

SHF
I agree; the location of an indoor antenna is critical.

If you look at my avatar to the left you will see a scan with my signal level meter for channel 13. I had put the antenna in the most convenient location, but I wasn't able to receive that channel because of indoor multipath reflections. This is what the TV Diagnostics Screen looked like; the picture is frozen, with many errors:



The best location was in the middle of the room in a high traffic area (of course it was), but I couldn't leave it there:





The second best was in the corner, where it is now.







Happy Thanksgiving to the AVS Forum members!
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post #17946 of 18323 Old 11-28-2019, 03:49 PM
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Quote:
Originally Posted by rabbit73 View Post
I agree; the location of an indoor antenna is critical.

...

Happy Thanksgiving to the AVS Forum members!
I thought my Kodak DC260 camera (199x Purchase) was dead, but it just was discharged Ni-Mh batteries.

The antenna placement picture is not the most important picture.

The tuner is a Silicon Dust HDHR4-2US and it is connected to my router using the 110V AC Power Line.

In the room with my Ethernet Router there is a matching 110V AC Power Line adapter.

That was how I went from 3 Mbs DSL to 12 Mbs cable which was then upped to 25 Mbs then 65 Mbs and finally 75 Mbs with increases in cost of course.

The change from 25 Mbs to 65 Mbs broke the 110V AC Power Line adapter. The internet would just disappear for five minutes ever so often. Cable technician keep saying get rid of the 110V AC Power Line adapter. But the internet comes in front downstairs while my router is rear upstairs.

I finally got the TV cable that I installed ~ 46 years ago to carry the internet up to my router / HDTV room.

Bottom line, with an Ethernet network connected to your HTPC you can put a remote antenna anywhere there is 110 V AC.

SHF



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post #17947 of 18323 Old 12-08-2019, 11:54 AM
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If anyone is still using or looking for the RCA UHF/VHF input antenna amplifier, I noticed in that thread the other day that there is a new RCA model with only one input. So I would assume if you need the older one, you might want to check now. Here is my posting as I purchased one around four months ago which is still the old model with a very similar product number:

https://www.avsforum.com/forum/25-hd...l#post58928248
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post #17948 of 18323 Old 01-06-2020, 08:59 PM
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Quote:
Originally Posted by rabbit73 View Post


The log periodic array is becoming more common for shortwave broadcast to allow for changes in frequency.

As far as why did Antennas Direct choose that design for the DB4e, you would have to ask the engineer they hired to design it. It was probably the same engineer, Dr. John Ross, who came up with the tapered loop for their UHF antennas, which has good gain and a wide beamwidth. The DB4e was one of their first antennas that was designed for the then smaller 14-51 UHF band.

I'm thinking 80mm was the "radius" of the inner loop? I printed it and measured the two circles and that makes sense but I'm not sure since that may be a rough sketch and not drawn perfectly to scale.
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post #17949 of 18323 Old 01-07-2020, 10:18 AM
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I'm thinking 80mm was the "radius" of the inner loop? I printed it and measured the two circles and that makes sense but I'm not sure since that may be a rough sketch and not drawn perfectly to scale.
That is possible; the original drawing came from the patent application. Often, the finished product isn't quite the same as described in the patent. You would have to open the antenna to measure the loop.



http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html
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post #17950 of 18323 Old 01-07-2020, 10:23 AM
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You would have to open the antenna to measure the loop.
Has anyone done that? And has anyone replicated balun or combining networks for Clearstream models? The 2MAX would be a good start since it's a popular model and also indoor friendly.
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post #17951 of 18323 Old 01-07-2020, 10:45 AM
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Originally Posted by labjr View Post
Has anyone done that? And has anyone replicated balun or combining networks for Clearstream models? The 2MAX would be a good start since it's a popular model and also indoor friendly.
Well, Ken Nist, MSEE (ret), KQ6QV who created the hdtvprimer site had to open it up for the above photo, but he didn't give any measurements of the UHF loop.

Forum member holl_ands modeled the C2, and gave these dimensions:
DIMENSIONS Per ADTech and user freezer:
Inner Loop Diameter 6-1/4" (158.75 mm), Outer Loop Diameter 8-5/8" (219.075 mm) with 1/2" Overlap at Feedpoint.
https://imageevent.com/holl_ands/loo...taperedloopc2v

Quote:
Originally Posted by ADTech View Post
You know, sometimes the best way to get accurate information is to simply ask someone who has it. I'm not hard to find...

UHF tapered loop dimensions, all versions:
ID 6.25" , ~ 16 mm (should be 160 mm)
OD 8 5/8", ~ 22 mm (should be 220 mm)
Element gap between feed points - 3/32", ~ 5 mm (should be 2.38 mm)
Element width at feed point, 1/2", ~ 13mm
Feed point spacing, 1 7/16", ~ 37 mm
https://www.digitalhome.ca/forum/186...ml#post2467962

So, you were correct: "80 mm" is the radius, not the diameter as stated in the patent application.

There is also a thread:
Clearstream C2 and C4 Dimensions
https://www.digitalhome.ca/forum/186...imensions.html



This is the circuit board for the CS4 MAX:

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post #17952 of 18323 Old 01-07-2020, 11:55 AM
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Dr. John Ross designed the UHF tapered loop for the ClearStream antenna. Here is his presentation:
http://www.johnross.com/SBE_2008.pdf

and here are some of his comments on the design:
Quote:

JER
12-16-2009, 09:14 AM
Its been known for long time that thick elements have wider bandwidth than thin elements. The developers of the Radion and Channel Master antennas were apparently trying to take advantage of that concept.

I was not aware of either of these elements until the photos were posted here by EV. They look remarkably similar to the first thick wide flat loop element that I prototyped early in the Clearstream development process. You can see a photo of mine in a paper I presented to the SBE in Pittsburgh last year. The paper is on my website if you're interested.

In the case of the Clearstream antennas we were aiming for a very compact loop - reflector combo with good gain and VSWR across the post 2009 UHF band. In my research, I discovered that element thickness only tells part of the story and I ultimately found the tapered loop element to be better than loops that were uniformly thick like the one above.

The thing surprises me the most is that these photos show that the thick element concept was known and used early on in television. Yet, the vast majority of the modern indoor loop elements that I've seen are made with thin wires and employ manually controlled tuning networks to peak signal on one or a few channels rather than trying to receive the whole band at once. The manual adjustments and narrow tuneable bandwidth haven't made any sense to me since the introduction of the remote control. Its been a mystery to me how such antennas could be sold to people that didn't want to get out of the easy chair to adjust the antenna every time they changed channels when a simple wide thick element would have eliminated most of that hassle.

Looking back, I suppose the other advantage with the early generation receivers may have been that the tuneable loops might have acted as a pre-selector to improve performance. The preselector idea can still be an advantage today, but the convenience of the remote control and channel surfing generally should take first priority in the design.

A tuneable bandwidth antenna that is compatible with channel surfing can be realised using smart antenna technology. I have designed and demonstrated such antennas but the market is not quite ready yet since most TV's don't yet have a smart antenna interface.

As a final note, I don't think the existence of the Radion element detracts from or otherwise invalidates the innovations in the Clearstream antennas. Had the notion of the optimised compact tapered loop - reflector combination been obvious then it wouldn't have taken until now to see such items available in the market place!
Clearstream antennas
https://www.digitalhome.ca/forum/81-...tml#post885276


Quote:
JER3
2009-02-21, 01:20 PM

I'm the engineer that developed the Clearstream geometries for Antennas Direct. I don't usually have time to post to forums but I do monitor some of them from time to time looking to see feed back from consumers on my designs. I saw this thread I thought I'd take a few minutes to try to clear some of the FUD (fear uncertainty & doubt).

First of all, you don't need to worry, Antennas Direct is not trying to hide anything by showing a plot of directivity. The curves are generated using state of the art computer simulation software (Remcom X-FDTD). We are not afraid to show curves. That should be encouraging to you since many consumer grade antennas don't come with any tech data whatsoever.

We also test antennas using network analyzers (e.g. HP 8510C) and do field testing using spectrum analyzers (HP 8569A and HP 8566B) and consumer grade receivers. Antennas Direct is really doing serious antenna engineering and is trying to innovate in a field that has not changed substantially in a long time. We're a small company and sometimes the science and marketing get out of sync but rest assured we're doing all we can to get you good products.

The Clearstreams are based on the classic idea of a full wave loop in front a reflector. This was known for years to produce about 9 dBi gain (infinite reflector) if you could properly feed it.

Note that there is nothing wrong with specifying gain in dBi as oppose to dBd. The manufacturer isn't just trying to inflate numbers. dBi is actually the most commonly used reference in most of the professional antenna literature (e.g. IEEE). It is also the figure provided by all the simulation packages. The dipole reference is fine if you're doing field or lab testing. Directivity equals gain dBi for an antenna with no loss (not including mismatch). The simulator was configured to assume perfect electric conductors hence the plot labeled with directivity instead of gain. I'll talk to the marketing folks and see if I can get a new one with gain on the label...

I applied computer simulations, optimization algorithms and lab testing to figure out how to size and taper the design with a small reflector so that it would perform well across the whole post 2009 UHF DTV band. UHF is targeted since that's where 75% of the stations are transmitting and since most consumers want smaller rather than than larger antennas.

My simulations and tests have shown the C1 generally offers performance as good as a two element bow tie in about half the volume. The C2 is comparable to DB4 across UHF but smaller and better on VHF.

If you look at properly executed simulations you will find that the bow-ties don't reach peak performance until the frequency is above 700 MHz. This is because they were engineered for the old band allocations. The Clearstreams achieve even balanced performance across the new band allocation. The C1 and C2 offer a horizontal plane 1/2 power beam width of about 70 degrees. Unlike many antennas (e.g. bow-ties) whose beams get narrower as the frequency is increased, the beam width of the Clearstreams is almost constant across the band. This makes pointing and installation easier for most consumers.

The Clearstreams also generally work better on VHF. This is a characteristic of the loop geometry and the fact that there is a phase cancellation effect for frequencies below design passband on the four element bow-tie arrays.

We do not specify VHF performance on the C1, C2 and C4 because it is below the design passband and the PCB baluns do not produce a balanced antennas at low frequencies. The latter however enables reception from what is known as feedline radiation. While this is usually avoided for transmitting antennas, on receive it can in fact enhance reception on the out-of-band (i.e. not in design window) frequencies. The effect is quite dependent on installation specifics so your "mileage may vary" but this is still sufficient for many consumers near the VHF stations.

For those wanting to receive weaker VHF stations a separate VHF only antenna with a diplexer should solve the problem. Antennas Direct C5 is a derivative of the C1 for high VHF and should be on the market in a few months.

I know this is a bit long for a first time post but I hope that you find it helpful.

I'll try to check in again from time to time.

Best Wishes,

John Ross, Ph.D., P.E.

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post #17953 of 18323 Old 01-07-2020, 06:34 PM
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Yes the Radion loop antenna is well known among all antenna engineers and is a 75 year old design.
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post #17954 of 18323 Old 01-07-2020, 06:44 PM
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Thanks for the information. I'm not sure how much of it I could replicate, but it will keep me busy for a while.
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post #17955 of 18323 Old 01-07-2020, 06:48 PM
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I'm glad you found something useful, labjr.

Radion loop antenna:


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post #17956 of 18323 Old 01-07-2020, 07:00 PM
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Obviously AD antennas were designed with some engineering talent not just a gimmick. The fine details are probably an important part of getting the most performance out of it. However I'd still like to try making something. Maybe experiment with a single tapered loop and a piece of coax and some kind of balun. Do you know what the impedance for a single loop is?

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post #17957 of 18323 Old 01-07-2020, 07:36 PM
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My guess is about 100 ohms. Dr. Ross used an ordinary 4:1 (300 to 75) balun for his prototypes.
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post #17958 of 18323 Old 01-08-2020, 02:13 PM
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Stellar Labs #30-2435 FM Hoop Antenna

Based on discussions here I purchased one of these for my omni-directional antenna update. I am currently using an ancient Channel Master 8200U with a rotor.

When I received the antenna I was surprised to see that the directional pattern differed significantly from @holl_ands posted simulations and I am wondering why that is. A couple of things stick out. The first being the metallic boom that bisects the loop. The second thing that I notice is that active (and only) element is grounded to the boom.

I have attached a file with the printed documentation that came with the antenna. The directionality plot is not labeled as to which direction are the lobes and nulls. Does anyone else have a better idea of the actual gain and directionality of this antenna?

BTW, I currently have it connected to my stereo setup and it is sitting on top of a book case. The results, while not spectacular are better than the 8200U in a random off-axis direction which is aimed for TV reception.
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File Type: pdf Stellar Labs #30-2435 FM loop - Instructions.pdf (466.1 KB, 10 views)
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post #17959 of 18323 Old 01-08-2020, 03:38 PM
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I find it interesting that the box says:
Quote:

Take advantage of free HD television programming
Quote:
Originally Posted by Steve347 View Post
When I received the antenna I was surprised to see that the directional pattern differed significantly from @holl_ands posted simulations and I am wondering why that is.
The pattern scale for the 2435 isn't marked; the difference probably isn't that great.



Quote:
The first being the metallic boom that bisects the loop.
That might make a difference.
Quote:
The second thing that I notice is that active (and only) element is grounded to the boom.
That's OK; it's a zero voltage point in the top half-wave section. It will help to protect the front end of your FM tuner from static discharge if the mast is grounded.

Quote:
Does anyone else have a better idea of the actual gain and directionality of this antenna?
It looks very much like holl-ands'.
https://imageevent.com/holl_ands/omni/doublehoop

An Omni sacrifices gain for an omni pattern. If you need more gain in a certain direction, you will have to use a Yagi.

Quote:
BTW, I currently have it connected to my stereo setup and it is sitting on top of a book case. The results, while not spectacular are better than the 8200U in a random off-axis direction which is aimed for TV reception.
Sounds like it's doing OK.
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post #17960 of 18323 Old 01-08-2020, 04:53 PM
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Quote:
Originally Posted by Steve347 View Post
Stellar Labs #30-2435 FM Hoop Antenna

Based on discussions here I purchased one of these for my omni-directional antenna update. I am currently using an ancient Channel Master 8200U with a rotor.

When I received the antenna I was surprised to see that the directional pattern differed significantly from @holl_ands posted simulations and I am wondering why that is. A couple of things stick out. The first being the metallic boom that bisects the loop. The second thing that I notice is that active (and only) element is grounded to the boom.

I have attached a file with the printed documentation that came with the antenna. The directionality plot is not labeled as to which direction are the lobes and nulls. Does anyone else have a better idea of the actual gain and directionality of this antenna?

BTW, I currently have it connected to my stereo setup and it is sitting on top of a book case. The results, while not spectacular are better than the 8200U in a random off-axis direction which is aimed for TV reception.
The boom probably has some effect on the pattern, but I would guess it is minor. Where the element is attached to the boom is a voltage null, no problem. By definition, omnidirectional indicates it should receive equally well in all directions so there shouldn't be any directionality to speak of (as long as its mounted in a horizonal plane.) I would suspect an antenna of this design has no gain, probably 2 or 3 dB loss as compared to a dipole since it is omnidirectional.

Edit: Oops, I was too quick on the trigger and didn't scan further down the thread. Rabbit73 had already answered.
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post #17961 of 18323 Old 01-08-2020, 06:56 PM
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That's OK; both answers are useful for Steve. Actually, our answers are quite similar.

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post #17962 of 18323 Old 01-12-2020, 11:28 AM
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Quote:
Originally Posted by rabbit73 View Post
That is possible; the original drawing came from the patent application. Often, the finished product isn't quite the same as described in the patent. You would have to open the antenna to measure the loop.



http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html
The older patent from 2009 seems like a more accurate rendition of the tapered loops. The ends are parallel like they appear to be in the actual antenna. However, still uncertain the dimensions are drawn proportionally accurate. And may have changed since 2009.
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post #17963 of 18323 Old 01-12-2020, 01:41 PM
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Quote:
Originally Posted by labjr View Post
The older patent from 2009 seems like a more accurate rendition of the tapered loops. The ends are parallel like they appear to be in the actual antenna. However, still uncertain the dimensions are drawn proportionally accurate. And may have changed since 2009.
Thank you for the design patent number US D598,434; I didn't have that. There is no text that gives measurements.

You did ask about the single loop; the older drawing has a wider gap. I would make the gap at the feedpoint smaller like just one loop of the double loop C2 because the new UHF band is lower in frequency.

I enlarged the loops in the design patent pdf to 157%. The OD was 220 mm; the ID 160 mm.

I don't know if the dimensions are the same in the new MAX series.
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Last edited by rabbit73; 01-12-2020 at 03:58 PM.
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post #17964 of 18323 Old 01-12-2020, 03:22 PM
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Here's a video of a teardown of a single loop with reflector screen. I wonder if they changed the loop design in 2015? Maybe the reason for the new patent?


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post #17965 of 18323 Old 01-12-2020, 05:04 PM
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Quote:
Originally Posted by labjr View Post
Here's a video of a teardown of a single loop with reflector screen. I wonder if they changed the loop design in 2015? Maybe the reason for the new patent?

https://youtu.be/SxlMyutnO3A
Good find; Danny took it apart.

The design in the patent was for theory; the design in the actual antenna was for practical construction. A design patent actually gives Antennas Direct more protection.

The balun printed circuit board seems to show a direct connection for the coax with an extra track on one side connected to the shield, but it's hard to tell without more detail.
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Last edited by rabbit73; 01-12-2020 at 06:51 PM.
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post #17966 of 18323 Old 01-12-2020, 05:35 PM
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Yeah, I'd like to see the detail of that PCB. It looks similar to the Balun PCB in the picture you posted the other day.

Last edited by labjr; 01-12-2020 at 05:55 PM.
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post #17967 of 18323 Old 01-14-2020, 07:25 PM
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There is a new version of the double loop version now called Clearstream MAX-V. It is sold at Walmart and directly from Antennas Direct. Don't know if they have modified the size of the loops or changed the balun. And they still sell the Clearstream 4MAX at Best Buy, and other versions such as 2MAX, 2V, and 4V are still sold from Antennas Direct and various vendors. The versions with the reflector screen should help add more gain, while the versions without the reflector are more bidirectional. And there is a new double loop version of the Clearstream Elipse for indoor spaces.

I use the original Clearstream 4 without the dipole in my attic, and Winegard LNA200 preamp. It is a strong UHF antenna in a compact size that fits better within the rafters. Whatever the technical specs may be, I have found the various Clearstream antennas to be strong performers, especially for UHF. I use a UVSJ from Radioshack to splice in my VHF signals with a separate set of rabbit ears.
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post #17968 of 18323 Old 01-14-2020, 08:57 PM
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Thanks,

I saw a comment by Antennas Direct Tech support, which I can't find now, that said the Max-V was the same antenna as the 2Max. I bought a 2MAX at Walmart on clearance. But I still want to build one and compare. Replicating the balun is the difficult part.

Also Alibaba has a couple antennas that look like Clearstream antennas.
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post #17969 of 18323 Old 01-14-2020, 10:23 PM
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Hi Rabbit. Happy new year!

So I finally set up my antenna (HD Stacker) on a 20' mast this week and the results were somewhat mixed. I was able to receive KNSD, KSWB, and KPBS however they are unwatchable with several drop outs every few minutes. KNSD is by far the most reliable among the three. My TV also picked up KFMB but it does not come in. On my TV's signal meter they range from no signal (about 40%) all the way up to 80% in some cases. The SNR read out on the screen ranges from 0 to up to 25. Here's a screen shot of what I've been typically receiving. Any thoughts?
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post #17970 of 18323 Old 01-15-2020, 08:13 AM
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Quote:
Originally Posted by tylerSC View Post
There is a new version of the double loop version now called Clearstream MAX-V.
Thanks for your post about the new MAX-V.



The VHF dipole is held by clamps to the rear of the UHF loops. There doesn't seem to be a physical connection for the dipole; it must be capacitive coupling like the NAROD VHF elements of a Gray-Hoverman antenna.



The feedline is connected to the double loop by a push-on connector.



There isn't a reflector available for the MAX-V which would increase the forward gain and reject multipath reflections.
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Last edited by rabbit73; 01-15-2020 at 08:18 AM.
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