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Discussion Starter #1
Unless I've overlooked it in past threads, I haven't been able to locate a real head-to-head comparison of AC's Y10-7-13 versus Winegard's YA-1713.

They're both designed for upper VHF reception. Yes, there are published gain figures from the manufacturers but an unbiased "shootout" would be interesting.

So far my searching (both here and elsewhere on the web) indicates that, boom length differences aside, the two are virtually interchangeable. Given the apparent design dissimilarities, I would guess that the Y10-7-13 and YA-1713 would perform somewhat differently.
 

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re_nelson said:
...haven't been able to locate a real head-to-head comparison of AC's Y10-7-13 versus Winegard's YA-1713.
I think you are correct.

re_nelson said:
...but an unbiased "shootout" would be interesting.
Agreed.

re_nelson said:
... indicates that, boom length differences aside, the two are virtually interchangeable. Given the apparent design dissimilarities, I would guess that the Y10-7-13 and YA-1713 would perform somewhat differently.
They might perform differently, give or take dB.

You have seen the specs:

For Y10-7-13:

9.4 dB Gain* (for VHF band)​

The following gain numbers were provided in private communication with Antennacraft employee:

Code:
Ch. Gain* (dB)
8    8.9 
11  10.1
*over half-wave tuned dipole​

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For YA1713:

Code:
Ch. Gain** (dB) 
7    9.1 
9    10
11   10 
13   10.3
**over reference dipole​

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

In favor of the Y10-7-13

Antenna gain and bandwidth (to some degree) are improved with wider element spacing.​

In favor of the YA-1713

For use in 75 Ohms systems, the somewhat integrated 1:1 balun is probably less lossy than using a conventional 4:1 balun.​

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The main design difference seems to be the driven elements:

Winegard uses a 2-cell log design as driven elements vs. the dual-driven folded dipoles of the Antennacraft.

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Regarding comparing two similar antennas:

From: http://www.antennacraft.com/Support_.html

"A good rule of thumb is that an antenna of comparable size and configuration supplied by different manufacturers will likely give similar performance."

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If someone could provide dimensions of a Y10-7-13, then a comparison of NEC model simulation results of the Y10-7-13 vs. YA-1713 might provide some insight.

The YA-1713 has been looked at with NEC modeling (HDTVprimer, Holl_ands, & others), but the results are a bit confusing. The published NEC results indicate a substantial gain loss for the YA-1713 at channel 13, that likely does not exist (see Holl_ands work). My analysis using 4NEC2 based on my antennas and my field experience with the YA-1713 supports Holl_ands findings.

I have tested four YA-1713s and several other relatively high gain VHF antennas (but don’t have a Y10-7-13). In modeling YA-1713 & other VHF antennas (namely channel-cut antennas), I have noticed that NEC models consistently yield results that are shifted down a few MHz (as compared to actual field test measurements). This could be a source of modeling frustration that has been found with the YA-1713 (i.e. questions regarding model results showing a loss of gain at channel 13).

It could be that typical NEC2 models, in general, (or maybe only at VHF with typical Yagi implementations) show results shifted down in frequency a bit.

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Interpreting the results of field comparisons involving two antennas that have gains that are within a dB or two of each other can be tricky.

For example: the matching to a preamp, transmission line, or whatever is connected to an antenna can make a difference.

I have measured received power at 200 MHz delivered to a signal strength meter from an antenna as the coax transmission line was trimmed one inch at a time. The magnitude of the received power varied in a sinusoidal manner approaching 2 dB p-p variance as the decreasing line length went through multiples of 1/2 wavelengths. Also, when using the same antenna with a different preamp, the output varied very little with changes in transmission line length. In theory, more variation than 2 DB is possible.

There are many other factors: e.g. height above ground, nearness to other objects can affect a specific antenna in one way and different antenna in a different way.

In general, I think the two antennas (YA-1713 & Y10-7-13) might be close enough in performance that differences will come down to implementation and specific channels. These differences are some things that one would almost have to verify at their particular site.

Having said that, like you, I am interested in comparisons, data, and experiments with these antennas.
 

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I'd like to see a comparison as well. Right now I find the YA-1713 more favorable due to it's size (almost 2 feet shorter), lower shipped price (at least in the lower 48) & being 75 ohm ready.
 

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Discussion Starter #5
In general, I think the two antennas (YA-1713 & Y10-7-13) might be close enough in performance that differences will come down to implementation and specific channels. These differences are some things that one would almost have to verify at their particular site.

Having said that, like you, I am interested in comparisons, data, and experiments with these antennas.
Time (and finances) permitting, I may be able to obtain a Y10-7-13 sometime in early 2011. Being an antenna connoisseur (or perhaps more aptly, a dilettante), it would be entertaining to compare it with the YA-1713 I already have. The shipping charges for the Y10-7-13 that I've seen are around a third of the price of the antenna itself.

Given that the there won't be any postseason for the Dallas Cowboys this year, I will have some discretionary time on my hands for the Sencore and other measurement methods . :)

And D/FW is a fairly good market to test hi-VHF since we have channels 8, 9, 11 and 12 available. I do want to get the head-to-head comparison in before KTVT turns off RF-11 which I gather may happen in the next few months when they complete the final phase of the transititon to exclusively RF-19.
 

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Given that the there won't be any postseason for the Dallas Cowboys this year,
Heh, but maybe the Eagles will be able to use Jerry Jones' new stadium, he - he. As a consolation, if the Eagles clinch the division tomorrow, the Boys will probably win the last game the following week.
Update: Game time predicted blizzard might give the Vikes a boost. :( And whats the story with England ? 10" of snow, and they get all out of shape ??? My nephew just spent 5 days there in the airport.
 

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Discussion Starter #7
...if the Eagles clinch the division tomorrow...
Well...well...well...a little thing called nature intervened, didn't it? :) Stay warm somewhere in Delaware and other locations along the US northeastern seaboard!

Back to the topic, I am seriously exploring that Y10-7-13 purchase I alluded to upthread. It appears that Summit Source has the best price. Agree?

How is it configured? Is it in two pieces (like the YA-1713)? Looking at the picture in the AC tech spec sheet, it's a bit hard to tell.

Any thoughts from those following this thread are appreciated.
 

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It seems as though it would be shipped in 2 pieces. It's shipping cost is indicative of a box slightly longer that the YA-1713.
 

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Discussion Starter #9 (Edited)
I'll be doing a shootout between the Winegard YA-1713 vs. the AntennaCraft Y10-7-13 within the next week to 10 days.

The AC Y10-7-13 I ordered just now arrived and because my time is currently tight, I just tossed it in the attic (with just the rear boom, essentially transforming it into a Y6-7-13). I didn't bother with trying to tweak its position for optimal aiming.

Nevertheless, the early results show great promise and lead me to believe that AntennaCraft is quite conservative with its gain figures.

My only complaint so far with this AC high-V antenna is that the strain relief is a considerable distance (45 cm or so) from the downlead connection terminals. I guess another "complaint" is that the spec sheet (in PDF form) depicts an antenna with only 9 elements. Perhaps that's just AntennaCraft under-promising but over-delivering? :)

http://antennacraft.com/pdfs/Y10-7-13.pdf

Watch for a followup with more data in the days ahead.
 

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lead me to believe that AntennaCraft is quite conservative with its gain figures.
Yeah, AntennaCraft posts fair numbers.

But the minute their antennas arrive at Radio Shack, Radio Shack starts making crazy mileage claims for them, heh.
 

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To Measure a VHF Yagi Type Antenna

If anyone wants to measure a VHF Yagi or similar antenna for NEC analysis, these are some tips:

Measure and record:
1. The diameter of the boom. The boom if frequently made of square stock, measure across one side (often one inch).

2. The diameter of all elements (often 3/8 inch stock).

3. The length (end-to-end) and the position of all the elements.
For example start with the reflector, often but not always the longest element, measure its length (end-to-end, x.x inches), call it #1, specify its position as zero inches (or meters).
4. The length of the driven element(s) and specify position(s) as x.x inches from the reflector.
Driven elements (DE) are usually insulated from the boom (more about DE further down the list).
4. In a similar manner, measure and record lengths of all elements and their positions relative to the reflector.

5. Measure overhang at ends of the boom; the center of the first and last element to end of boom, often about an inch. (Not usually necessary, but can be helpful)
As an alternative to measuring spacing distances relative to the reflector, one could measure spacing between each element.
6. Inspect the driven element(s), measure & record spacing between feed points, where the feed line connects.
If driven element(s) is (are) folded, measure diameter of all parts of the fold. Sometimes a folded dipole has a third fold (or shorting bar) usually across the middle of the folded part, measure the diameter of all sections.
a. Measure longest portion end-to-end (usually at middle of fold).

b. Measure spacing between all portions of folds (center to center). This can also be measured from side-to-side of tubing.

c. Inspect one folded end; at some distance from the curved end there will be a point that could be considered the bend radius. Imagine that the fold completed a circle. Measure or approximate the distance of this radius from the outer end of the folded element. If the fold has other peculiarities, try to find a way of quantifying.
Measure transmission line (between driven elements):
1. Diameter (if wire), or width and thickness (if strap).

2. Spacing between lines

3. Spacing between lines and boom
Photos may be necessary to ascertain measurements required for some configurations.


Notes:
- Measurements can be in inches or meters
For simplification, some measurements have been omitted: element-to-boom fasteners, element tapering at tips, active element shape near feed points, etc.
- Use the highest practical precision (for example: maybe 1/16 inch for the larger dimensions). Smaller dimensions such as element diameter and especially transmission lines require greater accuracy (a caliper can be helpful).

- If one measures the positions of each element with respect to each other, then for an accuracy check, compare the sum of all the element spacing(s) to the total measured length of the boom (less overhang)
A measurement procedure similar to the above could work for UHF antennas, but would need modification to take into account the different construction techniques commonly in use.
 

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Very nice directions, tripelo.
I basically say to write down all the detailed measurements, as if you were to throw the antenna away today, but would have to build an exact copy from scratch the following week.
 

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Discussion Starter #14
I don't think anyone has modeled the Y10-7-13....
Can you provide us with detailed dimensions, so that we might model it????
I just hauled it down from the attic and will do so within a few days following those outstanding instrucions that tripelo provided. My sole measurement tool for this is US Imperial-based only. Would it be preferred that I first convert to metric when I submit the dimensions?
 

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Would it be preferred that I first convert to metric when I submit the dimensions?
re_nelson is online now Report Post Quick reply to this message
Heh, thats the beauty of 4nec2, conversion is just a mouse click away.

Measure in what you feel most comfortable with, metric or inches. But of course, state what, heh.
 

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I look forward to a shootout between these two antennas.
 

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Discussion Starter #17
I look forward to a shootout between these two antennas.
Same here, since unless someone else steps up to the plate before me, I'll be doing it -- hopefully this weekend. :)

Since I did bring the Y10-7-13 down from its attic perch for measurments, I can offer this initial comparison between it and the YA-1713:

The two boom segments are FAR easier to separate on the AntennaCraft than the Winegard. The YA-1713 attaches very snugly (perhaps too snugly) between the two booms and is held in place with one nut/bolt combination that also holds one of the directors in place at the junction between the front and rear portion.

In contrast, the Y10-7-13 uses two bolts/wingnuts to secure the front boom to the rear boom using a configuration not dissimilar to that of the boom interconnects on the 91XG.

So, just in terms of ease of disassembling, the Y10-7-13 wins this round. I thought I was going to dislocate my arm from its socket as I strained to separate the two parts of the Winegard antenna since they wedge together so tightly.
 

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Discussion Starter #18
I don't think anyone has modeled the Y10-7-13....
Can you provide us with detailed dimensions, so that we might model it????
Thanks to the explicit and easy-to-follow directions from tripelo, someone even as ham-fisted and all-thumbs as me may have come up with useful data here.

Please perform sanity checking to make sure these appear reasonable. In the event of a botch, I have the Y10-7-13 close at hand and can correct. If something needs further elaboration, let me know. Measure twice, post one (hopefully):

Code:
Geometry from actual AntennaCraft Y10-7-13 measurements (by re_nelson 2011-01-21)
All 10 elements aluminium
ALL MEASUREMENTS ARE IN INCHES

Spacing        Size     Notes
-------        ----     -----
   N/A        1.00      Boom "diameter" (square)
   N/A        1.25      Folded dipole elements diameter
   N/A        0.85      Director and reflector elements diameter

 -1.00         N/A      Rear Boom Overhang

  0.00       34.15      Passive Reflector (Element #10)

 12.50       29.25      Folded Dipole Driven Element with Downlead Connection (Element #9)
              3.00      Folded Dipole Height (Element #9)
              1.25      Folded Dipole Radius [Half Circle] (Element #9)

             12.00      Transmission line length (Element #9 to element #8)
              0.25      Transmission line radius
              3.00      Spacing between 2 parallel transmission lines
              1.00      Spacing between boom edge to each tranmission line

 24.50       29.25      Folded Dipole Driven Element (Element #8)
              3.00      Folded Dipole Height (Element #8)
              1.25      Folded Dipole Radius [Half Circle] (Element #8)

 31.75       25.15      Passive Director (Element #7)

 42.85       24.00      Passive Director (Element #6)

 54.00       24.00      Passive Director (Element #5)

                        Front and Rear Boom join between elements #5 and #4

 65.50       24.00      Passive Director (Element #4)

 83.50       24.00      Passive Director (Element #3)

102.60       24.00      Passive Director (Element #2)

119.10       24.00      Passive Director (Element #1)

120.15         N/A      Front Boom Overhang
 

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Any chance of some pictures of the folded dipoles sections and their connections ?
 

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The YA-1713 attaches very snugly (perhaps too snugly). . . .
So, just in terms of ease of disassembling, the Y10-7-13 wins this round.
This varies quite a bit between different samples of the YA-1713. I have one that easily comes apart, & another that won't separate without damage.
 
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