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The above comments are pretty much spot-on WRT the comparisons.

One thing to keep in mind is that the tapered loop models C1 & C2 have a virtually flat gain vs frequency curve and and very uniform ~70° BW across the UHF design band. The bowtie antennas don't have either of those attributes so there is sometimes an advantage, besides convenience of size, in selecting one style over the other.
 

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C5 Antenna mounting / comparison

Good afternoon,

I recently purchased an AntennaCraft Y5-7-13 antenna to attempt to receive either my local VHF 12 or VHF 13 stations, mounting the antenna in my garage attic. The Y5713 is working great to pick up VHF 12, but will only pick up 13 if I walk with it outside of the garage and at that point get around 80-85% signal quality with my HDHomerun4.

Rather than mount a Y5713 on the roof, I'm toying with getting a ClearStream C5 that I would mount on an old Dish Network J-mount on the side of the house. The angle might be a little tight from the current location of the J-mount, but I think it might be do-able. I realize I will likely need to replace the J-mount itself with a 40" version, but wanted to ask how the C5 compares in gain to the Y-5-7-13?

What is the distance between the two mounting brackets? I think I may have a slightly smaller than 40" J-mount hanging around in the basement.

Also, does someone make a modified J-mount that would stick out further from the house? From the specs, it looks like the width of the C5 is 29", so the max distance from the center of the pole would be 14.5", but I don't think I need quite that sharp of an angle off the side of the house, anyway.

Lastly, does the C5 ever go on sale? :)


Thanks!!
 

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...but will only pick up 13 if I walk with it outside of the garage
So, you mount it outside and/or get a pre-amp for it.

but wanted to ask how the C5 compares in gain to the Y-5-7-13
You could find out for yourself but check here for the technical specs.
C5 --> https://www.antennasdirect.com/cmss_files/attachmentlibrary/C5 technical data with uhf.pdf
Y5713 --> http://www.antennacraft.net/pdfs/Y5-7-13.pdf

Also, does someone make a modified J-mount that would stick out further from the house?
My opinion is that trying to save a penny here will cost you dollars during the install. Why not just get what the antenna manufacturer recommends?

Lastly, does the C5 ever go on sale? :)
You may see an open box item on their site or on Amazon or a used item on fleabay. Your mileage may vary.
 

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VHF Retrofit Kit

Several places in this forum mention if you are installing both UHF and VHF antennas,

a) put the UHF antenna higher
b) separate them by at least 2 feet (maximum UHF wavelength)

But the VHF Retrofit Kit installation instructions seem to violate both of the above. What am I not understanding here? :confused:
 

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What am I not understanding here?
Compromise for consumer convenience. Have you ever seen a standard combo antenna with that much separation between the sections? As for the VHF-1, you can always mount it separately, that's in the directions.

Mounting the UHF antenna is more of a convention than a requirement. Put them where they work.
 

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Thanks ADTech. I'm guessing that the dipoles are small enough that the ill effects of having UHF and VHF antennas literally together are of little consequence? Less so than say, combining a C5 (with much more metal) with a UHF antenna immediately above it.

Some background - I have a C5 but when I mounted it below my DB4e, it's too low if I give it adequate spacing (that is, 2 feet as indicated in my previous post). I'm thinking I had a VHF retrofit kit, I could get the additional height I need while not material degrading my DB4e's UHF performance.

(A little off topic but might help you understand my situation - the C5 used to be on a 2nd mast about 25 feet away and it worked nicely because the 2nd mast was equivalent in height to the main mast, but I had to requisition the 2nd mast for a 2nd UHF antenna to pick up a couple of stations in the opposite direction. Relocating the C5 lower on the either mast didn't go well at all :( )
 

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I modeled d510d180's version of the Tapered-Loop (presumably a Klone of the C2), adding a 10" H x 20" W Screen Grid Reflector (per C2 Sell Sheet dimensions) with Tapered-Loop to Reflector Separation chosen for "best" performance and then a run adding Hi-VHF Dipole with Length Optimized for best fit of SWR across Hi-VHF Band:
http://www.digitalhome.ca/forum/showthread.php?p=2398785

I feared that the Reflector would have adverse effects on the nearby Dipole, but I found that there was only MINIMAL IMPACT of one Antenna on the other...primarily pushing the Hi-VHF Max Gain below the Horizon. So some locations, such as behind a nearby hill, may benefit from locating the Hi-VHF Dipole on the BOTTOM of the Antenna so it has a few tenths of a dB more Gain at Positive Elevation Look Angles.

PS: I'm looking for confirmation of ACTUAL C2-V Dimensions....I see that C2 Specs now say 20" L X 12" W, whereas original "Sell Sheet" said 20" L X 10" W, so there MAY be at least TWO versions?????
 

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The new Juice pre-amp

Curious how the Juice is for people with a mix of strong, middling and weak signals? The literature says it's good at avoiding overloads.

My situation in Toronto sees a mix of strong Toronto & Buffalo signals, medium strength Buffalo/Hamilton signals (and 1 crazy T.O. signal) and some Buffalo/Rochester signals that are borderline to locking in. (I wouldn't call them tropo signals, just temperamental i.e. they'll be good for several days then act flaky, or disappear throughout the entire year.)

Would the Juice be good for situations 2 & 3 without making the strong signals overload my HDHomerun?
 

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dheian, looks like a re-branding of their discontinued CPA-19 antenna without the large plastic shroud. I use a CPA-19 and it works well. Helps beef up the signal from a couple of buffalo stations and doesn't seem to cause any overloading with the close stations coming from the CNTower.

There's someone selling a CPA-19 in Mississauga on Kijiji
 

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Yes, the Juice is pretty much a re-done CPA19. We had to change manufacturers so we redid the name, the physical packaging (we kept the metal injection mold), the power supply and, internally, the filtering. The CPA19 had a filter that suppressed between 250 and 400+ MHZ, the Juice deleted that filter and replaced it with one that rolls in just above 700 MHz for 4G/cellular suppression. There was only enough circuit board real estate available for that one filter, so it's the only one in the Juice. FM filtering, if needed, can be done with one of our external full band filters.

Gain averages about +18 dB +/- ~1 dB across design band of 54-698 MHz.

Noise figure averages around 2.5 dB in low-VHF, ~1.75 in high VHF, and averages sub 3 dB on UHF. The gradual roll-in of the 4G filter slightly affects the top end of the UHF band. TANSTAAFL, as they say.

As far as IMD performance, it tests out to between +35 and +38 dBm TOI (Third Order Intercept), depending on the frequency at which it is tested. My personal observation is that this model is the most overload resistant amp that's come across my workbench so far.

For those who hate TOI results, I've tested a few other protocols. Frankly, testing this thing for overload is a PITA because my test gear doesn't readily produce hot enough signals and the dynamic range of the Rigol isn't all that wide. It is necessary to use attenuation on its input to keep the mixer input below -10 dBm so it doesn't introduce any IMD of its own which affects the ability to display weak and strong signals at the same. Depending on the RBW and attenuation settings, it's hard to achieve 70 dB of dynamic range. But, hey, it's a $2K piece of gear, several 10s of thousands of dollars.

A sampling of test results:
505 MHz with IP3 @ -46 dBc --- +61.9 dBmV (+13.1 dBm) fundamental output
505 MHz with IP3 @ -60 dBc --- + 7.7 dBm (TOI=37-38 dBm) fundamental output
DIN45004B 3-tone @~500 MHz --- 119.35 dBuV

Several notes: Samples from the same batch of amps will vary, sometimes by several dB. Also note that the Rigol's accuracy is somewhat limited in its precision (+/- 1 or 1.5dB IIRC). Far more accurate lab gear would reduce the results range for greater accuracy but that is outside my assigned charter. In general, the readings taken with the Rigol are very close to those obtained by our test lab engineer in his facility with his HP/Agilent gear.

P1dB test results usually ranged between +21 to just over +23 dBm depending on the individual sample and the test frequency.

I will be happy to try to answer any performance related questions that you might have.
 

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The UVSJ on the C2-V-REF, a re-labeled Holland, passes power on the VHF port. The EU385CF U/V combiner available as a separate item), passes power on the UHF port.
Is there a special 75-ohm to 75-ohm 1:1 Balun provided when connecting C2-V's Dipole to the VHF/UHF Combiner...or is the Dipole simply terminated directly into 75-ohm input of UVSJ???
 

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First and second generation C2Vs used a standard 300/75 ohm matching transformer to match the dipole to the Holland UVSJ's VHF input. Because of the built-in mismatch, the length of the dipoles was increased to bring the return loss back down in the center of the VHF band.

Third generation C2Vs that utilize the VHF-1 module utilize a custom PCB matching network that's closer to a 1:1 ratio, allowing the dipole elements to be shortened by 3.25" inches each while still having the best return loss at mid-band. The VHF-1 module includes the UVSJ function internally.
 

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91XG gone wonky on low UHF

Have had my 91XG up for about 3 years and recently noticed that one particular frequency (RF 14) is not being picked up with the usual signal strength. Interestingly, all others channels have seen no noticeable difference.
RF 15 might have decreased slightly, but it's tower is 3 miles from my house, RF 14 is about 45 miles away.

Here is my TV Fool: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=f1f03e054a5689

I've been told it might be a water issue in the balun, and that it needs to be cleaned out. I'm hoping it dries-out/corrects itself, otherwise it gives me more reason to replace the 91XG...
 

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Sounds pretty unlikely that the balun would cause such an indication. If it were water infiltration, the effect wouldn't be so narrow.

More likely is that the strong nearby station is causing decodability issues due to adjacent channel bleed-over and your TV set/tuner is erroneously reporting the increased error rate as a reduction in signal "strength".
 

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Not sure how much of an issue that is.

I have a db4e 10 feet lower on the tower and RF 14 comes in fine, different baluns though...
 

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The relative field strengths can vary significantly with a 10' vertical span and the variation might be opposite what you believe to be logical. They can also change with the seasons.
 

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Funny how the field strengths were fine for a few years (RF 14 was rock solid on the 91XG for 3 years), and then the field strength dropped dramatically and RF 14 is now a no-show..., but still a solid lock (over 3 years) with the db4e...
 

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I understand your point, but why was the loss of the channel overnight? You would think with those numbers you referenced, that RF 14 would be inconsistent at my location, however, it was rock solid ever since the 91XG and CPA-19 went up over 3 years ago. It's only in the last week or two that the signal has gone down and stayed down; it's not receivable, while my db4e picks it up fine...
 
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