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Old 5-Oct-2015, 3:55 PM   #1
TickingMind
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Join Date: Mar 2011
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Question Focus 8 Bay not impressed yet....

Picked this up last weekend to replace an aging setup. Yagi with missing elements and a rotor that has seen better days. Left over from the previous owner. This was on a roof tripod replace by a J-Pole on the roof peak.

https://angelelectronics.ca/shop/ota.../focus-8hd-90d



I'm at Hwy 6 & Hwy 403 (Hamilton area), Toronto is pretty much a clear shot, one bay is pointed that way, the other is swung south for Buffalo.

CM 7777 mast mounted. I think this is what made my previous setup continue to work until I lost another two elements with the wind and there goes three channels.

50 feet RG6 to a Motorola distribution amp, 3 TV's from there with a CM-3213 splitter.

First scan done, here is the shocker. CHCH-TV would not come in. I can see the tower from my place. CBC (5) nothing. CITY (57) nothing.
17, 23, 35,36, audio on 43, and that's it.

Swung the panels together, pointing towards Toronto. 57 pops in and out, same with 5.

I was a little stunned by the lackluster performance but thought of only one thing that might be a variable - overload? Disconnected the 7777 and directly connected the antenna to home. Even worse performance.

Something is really wrong...if this is the "fresh out of the box brand new antenna" performance then it's going back.

Anyone tried one of these? For all I know it could just be a bad connection in one of the baluns or something. Cable tests ok on both panels. Very odd.
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Old 6-Oct-2015, 1:23 AM   #2
rabbit73
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What does your tvfool report look like? I think that intersection is in Burlington and it looks like overload territory.
http://www.tvfool.com/?option=com_wr...8e03d699db91ba

I'm not impressed with the 8-bay antenna when the two sections are aimed in different directions; it rarely works as promised because when the same signals arrive at the combining point they interfere with each other.
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Last edited by rabbit73; 6-Oct-2015 at 1:27 AM.
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Old 6-Oct-2015, 2:04 AM   #3
TickingMind
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Quote:
Originally Posted by rabbit73 View Post
What does your tvfool report look like? I think that intersection is in Burlington and it looks like overload territory.
http://www.tvfool.com/?option=com_wr...8e03d699db91ba

I'm not impressed with the 8-bay antenna when the two sections are aimed in different directions; it rarely works as promised because when the same signals arrive at the combining point they interfere with each other.
I agree with the 8 bay, swinging them in different directions. I anticipated some degree of signal loss with the combiner though, to overcome this, but still up in the air about the performance.
TV Fool is here: http://www.tvfool.com/?option=com_wr...8e03cff352fbfe

Pretty much bang on, but listening for Buffalo, Rochester, Toronto was never an issue in the past, now I am thinking more like I need an attenuator, but removing the amp seemed to make things worse !?!
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Old 6-Oct-2015, 2:10 PM   #4
rickbb
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2 things I would try;

1st try just one 4 bay panel connected and aimed due east, 90 degrees, no preamp. Splitting the difference between your towers.

2nd try both panels aimed east, at most only 5 or 10 degrees apart from each other, no preamp. Again splitting the difference between the towers.

I think you have 2 issues here, one is overload from the close towers, you have 3 with a NM greater than 60db. The second is multipath from the 2 panels aimed in different directions.

An 8 bay is more directional than a 4 bay, I'm thinking that with the 60 degree beam width of a 4 bay and splitting the difference in directions you should be able to pull in a better spread of channels.

Of course there's no accounting for the trees and since they are pine they will be in the way year round.

Edit, I also noticed you also have a distribution amp so you are doubling up the signal of really strong close towers.

Last edited by rickbb; 6-Oct-2015 at 2:13 PM. Reason: add info
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Old 7-Oct-2015, 2:03 AM   #5
TickingMind
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Quote:
Originally Posted by rickbb View Post
2 things I would try;

1st try just one 4 bay panel connected and aimed due east, 90 degrees, no preamp. Splitting the difference between your towers.

2nd try both panels aimed east, at most only 5 or 10 degrees apart from each other, no preamp. Again splitting the difference between the towers.

I think you have 2 issues here, one is overload from the close towers, you have 3 with a NM greater than 60db. The second is multipath from the 2 panels aimed in different directions.

An 8 bay is more directional than a 4 bay, I'm thinking that with the 60 degree beam width of a 4 bay and splitting the difference in directions you should be able to pull in a better spread of channels.

Of course there's no accounting for the trees and since they are pine they will be in the way year round.

Edit, I also noticed you also have a distribution amp so you are doubling up the signal of really strong close towers.
Very good food for thought. Of interest, this evening I disconnected one bay from the splitter at the antenna, so it was one panel pointed not necessarily due east, (more on that), but in the direction of what I thought would give me Toronto as the other antenna did and a portion of Lake Ontario exposure to try and grab Rochester if possible, as it has been in the past.

Toronto and Hamilton finally came in on first scan. All of Hamilton, most of Toronto, still missing 41 which is normally there. Buffalo 17 & 19, 23, 29 Yes.
So a few things come to mind.

I've got the panel situated southerly enough to get Buffalo and pickup Hamilton on the side by sheer proximity (or verge of overload) alone. The other side sees enough of the Toronto lobes to lock in based on the panels beamwidth.

But the panel is not pointing "east" as it is in my mind.
It's more like South - East.
I can look at the tower location in Google and visually get an idea where to point the panel to nail the CN Tower, no doubt I would get Hamilton at that point to, being proximity again, but at the expense of Buffalo?

Which is why I went with the 8 Bay. But you brought up something about the 5 to 10 degrees apart between each panel. I really would like to continue to try to improve to get Rochester, so to have the panels setup as such, one more "easterly" south, by 10 degrees, one more "westerly" south, I might have a chance, but that would infer the overload from Hamilton, so given your ideas, both panels having more of a easterly direction, still able to pickup hamilton from the side, hopefully Buffalo doesn't get wiped out (one panel will be the "finicky" one), I should hopefully be able to do this.
But back to the the original problem. I still haven't nailed if it's a bad splitter now, sheer overload, bad balun in a panel. I've got reception on the east panel. Tonight we have that for our nightly news, all we need for now, but you have me thinking.

As for the distribution amp, easy enough to take out and in fact it's on bypass right now so you are correct, it could worsen the overload. Will leave it like that for now. The TV's are not as numerous now in quantity or usage now that iptv and netflix have prevailed but I still love my OTA. So does the wife.

Thanks again for your input!
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