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Discussion Starter #1 (Edited)
I was checking for a newer antenna chart, and it looks like the last version was 2015.
I had a CM4228 which was pretty good. I switched to a DB8e which was just fine and brought in channels a hundred miles away.
I'm building a new house and carefully took the antenna down and stored it in the neighbour's yard. That didn't stop the builders from dropping some heavy equipment on it and crushing it.
So I'm replacing it when they get the roof on. I am about to order a new DB8e. So that's why I was checking for antenna updates.
laurie in ladner BC with a bust-up DB8e.
 

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Discussion Starter #3
I use the bays in the same direction. I got a marginally better reception on those distance channels (south) and sufficient signal on the backside for the near channels to the north. I did try it as a DB4 in both directions.
laurie
 

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After you factor in the 0.5 to 1.5+ dB LOSS in the DB-8e's RF Combiner [NOT included in below Comparison Chart], it and the less expensive CM4228HD (esp. with my HHH mod) are the BEST Commercial UHF Antennas you can buy...although W-G Hi-VHF/UHF Combo's outperform them on lower UHF Channels....and is significantly worse on upper UHF Channels.

FYI: Details re HHH mod to CM4228HD:
https://imageevent.com/holl_ands/multibay/8bayrefl

 

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Never saw the C4. In big signal Toronto area, "C2" (called 2V) works well with CM-7777 even when tucked behind a brick building at 7' high. I can only imagine results if it were installed properly at height on a roof. I am today experimentally removing reflector to see if this enhances certain US channels. In actual use, raw gain is likely just one important factor to consider.
 

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The C4 is the predecessor of the 4MAX; that is, the 4MAX is a redesign of the C4 that is easier to assemble.

Yes, gain is not the only factor to consider when selecting an antenna. The chart above by holl_ands only considers gain. Other factors are beamwidth and front to back ratio. The C4 has a beamwidth that is more narrow than the C2 for UHF. The "V" is for the dipole that covers VHF-High real channels 7-13.

https://www.antennasdirect.com/cmss_files/attachmentlibrary/pdf/C4-sellsheet.pdf

https://www.amazon.com/ClearStream-Indoor-Outdoor-HDTV-Antenna/dp/B001BRXW74

The right antenna for you depends upon the signals at your location and which signals you want. Sometimes, there is no single antenna that will give you all the channels you want.
 

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I am still LOVING my homebuilt FF4, are you working on anything that might approach 15.5-16dB gain on rf14?

I've seen the new FF4 you designed here:

https://imageevent.com/holl_ands/multibay/4bayrefl/newuhffreeform4bayscreenreflopt

Looks fantastic but if there are plans percolating in your design kitchen I'd love to hear about it.


Thanks, as always, I know there are technological limits to what you do but after following your posts and website you always seem to have "something up your sleeve" as far as improvements go, surprised you haven't been hired by Antennas Direct of Channel Master.
 

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FF6 is only a bit more complex than an FF4....

FF6 Six-Bay Bowtie for upcoming New UHF Band provides 15.2 dBi on 470 MHz (Ch14), rising to 17.8 dBi on 608 MHz:
https://imageevent.com/holl_ands/multibay/newuhffreeform6bayvdaropt

Whereas if you still need High Gain up thru Ch38-51, then the original FF6 is 15.0 to 16.4 to 16.0 to 17.0 dBi:
https://imageevent.com/holl_ands/multibay/uhf6baybowtievdar

A Vertical Stack of TWO FF6's [for current UHF Band] provides 18.2 to 20.6 to 20.3 dBi: [With about same Beamwidth as single FF6.]
https://imageevent.com/holl_ands/stacked/verticallystackeduhf/vertstackff6doubleanglerefl

And a Horizontal Stack of TWO FF6's [for current UHF Band] provides 17.7 to 19.5 to 18.9 to 19.6 dBi: [With Narrrower Beamwidth.]
https://imageevent.com/holl_ands/stacked/horizontallystackduhfantennas/horizstkff6vdarhhh
[Not shown in below Comparison Chart.]

IF you want even higher Gain, than you might want to consider repurposing an 8 to 10-ft Parabolic SAT DISH modified to use a suitable [small, wide Beamwidth] UHF Feed Antenna....including the Motorized MOUNT so you can precisely Steer it: [BTW: 8-LPDA Feed Antenna for 2-m Parabolic is likely NOT the Optimum Choice.]
https://imageevent.com/holl_ands/parabolic

 

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Higher gain doesn't mean better reception.
I have replaced many high gain yagis with simple 4 bay bowties over the past 40 years because those high gain antennas caused signal loss with the slightest movement.
And software predictions are fun to play with but are no predictor of actual gain in the real world.
 

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Yes, it WOULD be Great when/if A-D changes their DB-8e design for the New UHF Band (470-608 MHz), they also eliminate the Loss in the RF Combiner. Unfortunately, I don't have detailed Dimensions to construct a 4nec2 Model....and an HHH may or may NOT be completely compatible as the pointing angles for the two 4-Bays diverges from both straight ahead.
 

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I have a dB8e here holl_ands. It is currently on the roof, though next time I am up there I could take some measurements if necessary,

From previous notes, before hanging it, I believe the two 4 bays are 27" apart center to center. I was measuring because Bro in law was wanting to put up two dB4e at his cottage.

I do have a DB4e in the shed I could use to take some detailed measurements of the elements, etc.

I like the db8e for it's flexibilty. If you look at my tvfool (in my profile), I use one of the bays aimed at wpxj, and the other kinda toward Toronto,
so I am not using it for maximum gain.
In that config I can get the low power UHF repeater, CKVP (5kw max erp, <3.5 kw in my direction) about 30 mi west, and wpxj is a
more traditional high power station some 40 miles away to the east. In between all that is the CN Tower. Pretty much only miss 3 lowest power CN tower stations here,
Obviously the db8e isn't necessary for just the local stations here...
 

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When you consider that by May 2020 most US and Canadian OTA DTV will be below 608MHz (602 in Canada); are antennas with better gain in lower frequencies change the selection discussion?
 

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It SHOULD....and I would expect to see REVISED Antenna Designs, where the improvements should be very significant when they move the Max Gain from 700-800 MHz [depending on antenna] down to about 608 MHz....for first approximation (simple Re-Scale), simply slide curve to LEFT so Max is about 608 MHz....total Re-Optimization should be even better. PS: I also suspect that A-D can ALSO improve DB-4e...which is NOT significantly better on Low UHF Freqs than other commercial 4-Bay Designs.

BTW: I already posed FF4 and FF6 designs Re-Optimizied for NEW UHF Band [models assume 2"x2" Reflector, if smaller vertical grid F/B & F/R improve]:
https://imageevent.com/holl_ands/multibay/4bayrefl/newuhffreeform4bayscreenreflopt
https://imageevent.com/holl_ands/multibay/newuhffreeform6bayvdaropt

 

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Looks like the hd 7698 8200 is the one to get for the best new lower spectrum performance. But what does the "8200" mean?
I can only find Wineguard hd 7698? Whats the 8200?
Schoolbus
 
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