: ON - Ottawa, Vanier, Gloucester, Orleans - OTA



flavoie
2011-04-19, 08:11 AM
I do have to specify that your db8 may not be good enough for wnyf(CBS,fox)
The gain of the db8 at channel 18 UHF seems way lower than the winegard hd8800 or channel master 4228hd.

With worse or equivalent tvfool than yours we had good results with a 8800 or 4228hd

Mr Canoehead
2011-04-19, 10:39 AM
Thanks, I realize I'd probably need to get a better long range antenna. The DB8 does remarkably well in my attic though.
I am at the southern edge of Avalon so there isn't much blocking me from looking south.

flavoie
2011-04-19, 10:58 AM
The Hd8800 and cm4228hd, although of similar size, do much better at the lower channels. Your db8 does really well at channels 25 and up but lacks the other 2 antennas at lower channels and you really need the extra gain to pick such a far transmitter reliably. Google hdtvprimer db8 and find the net gain chart. You'll see the cliff of gain going down quickly on lower channels. If your harder to reach channel was higher than 25 then it would not be as much of a problem...

The other part of it is some people have hacked the db8 and i don't know how well it helps the gain for channel 18. You could look it up.

heemu
2011-04-21, 11:24 AM
See http://www.digitalhome.ca/forum/showthread.php?t=139586

roger1818
2011-04-21, 03:15 PM
heemu, Regarding GH design questions, I would ask in the design forum.

Regarding reception from CF, for most people the signals from CF should be strong enough to go through the reflector, but since you also have an apartment building between you and it, it is hard to say how much effect it will have. I would give it a try and see what happens.

jrmclean
2011-04-23, 02:30 PM
Sure. I will try and get some measurements. May not get any good photos of it unfolded if I choose to install it in my attic, but maybe one of the other guys who also bought one can get photos (there were four of us).

i took some snapshots and put some rough measurements together...posted in this thread.. (http://www.digitalhome.ca/forum/showthread.php?t=139654)

bowtie
2011-04-24, 12:50 PM
Hello all. I'm looking for a post transition antenna which I can attic mount without a rotor. Hopefully something which will also work with ch. 13.

I held a CM4228-HD out a second floor window and pointed it towards South Colton. I was able to pick up 18.1, 18.2, 18.3, 28.1, & 28.2 with about 30- 45% strength as well as all the local digital channels. When I moved the antenna into the attic, I pretty well lost 28.1 & 28.2 and the 18's were marginal.

I threw together a Steal Hawk with some aluminum grounding wire. Out the window I was just able to receive the 28's and the 18's were acceptable. Hung in the window, which directly faces South Colton, the 28's dropped off.

I would like to try making a SBGH or DBGH. Would someone be able to recommend a model which will work for my location. My coax run would be about 60 - 70 feet. If I require a pre-amp, how do I decide how much gain I need. I would be worried about over-driving my tuner with the stronger stations.

Thanks in advance. Here is my TVFool.http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8d17b8b9e5a42e

roger1818
2011-04-25, 10:41 AM
Hi bowtie and welcome.

Are you stuck with the idea of using one antenna for both VHF and UHF or could you have separate antennas? Are you also wanting Global on channel 6?

HWP
2011-04-25, 11:15 AM
Roger1818,

Recently I've become aware of the gain level of the Winegard 8800 eight-bay bowtie antenna -- especially on channels 14-50. It appears to test quite a bit better than even the most mammoth of outdoor antennas. Since you have some limitations on outdoor antennas at your place, I wonder if you have ever considered using one or two of these to try to pull-in the US channels from your attic? I wonder if it might work?

roger1818
2011-04-25, 11:37 AM
HWP, that is the antenna I am thinking of using. My biggest concern with it though is there is 37 degrees between WNPI/WCFE and HC, which is near a deep null for channel 20 on the HD-8800. So finding a direction that receives WCFE as well as CITY, CFMT, and CJMT post transition could be fun.

HWP
2011-04-25, 11:47 AM
With a little luck SunTV will go off-the-air and you won't have to worry about 20 anymore -- haha.

What I liked first about that 8-bay antenna is that it ships unassembled -- which means it can fit easily into attics. The box is 6 1/2 inches by 6 1/2 inches. The great specs for post-transition are a bonus.

roger1818
2011-04-25, 12:03 PM
Post transition 20 will be used by CJMT. CITY is on 17 and CFMT are on 27 so all should have similar nulls. All three are from HC.

If it stays on air, SunTV will move to 33 from CF.

Edit: Given that I am in Stittsville, this is probably the wrong thread to be discussing my situation.

HWP
2011-04-25, 12:12 PM
Oh, I thought Sun CKXT was moving to 20.

bowtie
2011-04-26, 06:48 AM
Hi Roger1818,

I probably will be getting a VHF lo antenna to pick up ch. 6. What do you recommend for UHF and ch 13?

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8d17b8b9e5a42e

roger1818
2011-04-26, 10:19 AM
bowtie, you have about 110 degrees separation between CF and HC, which will make things more challenging. The thing I find most surprising is you are only 6.6 miles from HC but only have LOS to CITY (and presumably CHCH post transition) on that tower. Any chance of having the antenna a bit higher to get LOS for all HC transmitters?

You have a good shot at receiving WNPI, WNYF and CKWS (on either 26 or 36). Are you interested in any of these? CKWS will be analog for the time being but might change in 2012. This information will affect your antenna choice.

bowtie
2011-04-26, 10:55 AM
roger1818, I am stuck with an attic install. I was recieving WNPI & WNYF with the CM4228-HD along with all the local digitals with the antenna pointed directly towards South Colton. When I moved the antenna into the attic WNPI & WNYF became marginal.

My goal is to recieve WNPI & WNYF plus all the local UHF and ch. 13 on one antenna without a rotor.

Would a model of a SBGH or DBGH perform better in my situation than the 4228?

flavoie
2011-04-26, 11:00 AM
bowtie, do you have a low noise figure preamp like the cm7777 ?
In my experience, a preamp helps in all situations from my location.

bowtie
2011-04-26, 11:15 AM
No pre-amp yet. I was hoping for a recomendation based on my location and antenna. I'm concerned about overloading my tuner because ch. 17 had a very strong signal when I was experimenting with the 4228.

roger1818
2011-04-26, 11:33 AM
Bowtie, Where was the antenna when you were able to receive WNPI and WNYF reliably?

The CM-4228 is one of the better options for a combined VHF-HI/UHF antenna. The HD8800 might be slightly better for WNPI/WNYF but it won't receive VHF-HI very well. I am not an expert on the SBGH or DBGH so I will defer that to someone else.

As for flavorie's suggestion of a pre-amp, I agree that it can help in many situations, but wouldn't say it will help in all situations. Traditional wisdom says a pre-amp is only beneficial if you have long cable runs (more than 50') or are splitting the signal for multiple tuners. The exception to this rule is if your tuner has a noisy first stage amp and thus benefits from a lower noise pre-amp (I suspect this is flavoie's situation). PC tuners tend to be quite noisy as PCs are noisy environments. The tuners in TVs and STBs often (though not always) have good first stage amps.

flavoie
2011-04-26, 11:37 AM
bowtie, I don't think you should worry about overloading your tuner especially from your attic. A good preamp will be worth it in my opinion even if you decide to change the antenna later. If you're thinking about a VHF antenna a 7777 makes even more sense with the dual input option for VHF & UHF.

Compare with my TVFool under my "homepage" in my profile.
I have a roof, mast-mounted cm4228hd with cm7777, with Quad RG6, pointed at WNPI/WNYF and have similar CFMT results but I have a shorter angle from HC channels than you so I <should> be receiving even more signal from HC.

I only ran into overdriving 1 of my tuners, the Hauppauge 2250, the others were fine. When I realized it, I just put it through a 4-way splitter before getting the signal in the tuner. Problem fixed.

In all cases (including putting a 4-way splitter in front of my 2250), I was getting a very good improvement in SNR with the 4 different tuners I used.