I still have problems with CHOT 40.1 . I get very good signal strength, yet I see pixelation, sometimes very bad. When I hook up with Media Center signal strength meter, I get 5 bars out of 5 for both of my tuners. WHen I turn to my Hauppauge signal meter, I get SNR of 22 or 23, way higher than where pixelation should start. But I see a "Correctable Error" count increasing when problems occur. I can't help but think it's a feed issue, but I have no other person confirming it either.

I may need to rotate the antenna away from WNYF so CHOT gets in more squarely off the back of my 4228hd.

Not sure if its a possibility...sometimes my 5/5 bar stations would peak and cause pixelation losses...my splitter took care of it for me.

Thanks a lot Mike.
I played with attenuation, and it didn't change. So I figured let's force it to use a different tuner by switching to another channel then hit record then go back to CHOT. Solved. I'll have to find out what tuner The problem is on but this is progress !

i am not sure how to read the diagram
These are gain charts for the antennas, showing how the gain varies with direction. The antenna is at the centre of the concentric circles. There are 2 views: an "overhead" view (i.e., viewed from above), which is generally the most important, and an "elevation" view (viewed from the side) which may also be useful in your case (in a valley).

The charts show the "normalized" gain for the antenna, meaning that the longest lobe extending to the outer concentric circle is the maximum gain for that antenna, and is normalized to 0 dB on the chart. The inner concentric circles represent lower gain levels (-10 dB, -20 dB, etc.) below the maximum, and the coloured lines show the gain for the different channels against these reference lines in the different directions. For example, at 90 degrees on the overhead view, the CM4228 drops down to between -40 and -50 dB below its normalized gain.

You would add the antenna's gain to get the effective gain in the direction of interest:
antenna gain + directional adjustment = gain in that direction

With your CM4228HD pointed at HC, you are of course maximizing the gain for those channels, but you are imposing a loss of greater than 40 dB on the CF UHF channels, reducing their margins significantly, and increasing the likelihood of dropouts on those channels. (My own experience with receiving signals off the side of an antenna has not been very good: very unstable.)

Note: The chart for the CM4228 turns out to be for the earlier model, but is probably very similar for the CM4228HD updated version. I don't know if an updated chart is available. But there is some very informative follow-up info on the following page, which you may find useful: http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html

I dont have any trouble at all receiving CF channels
they are solid
i am pointed to HC and have trouble receiving HC
even at 90 degrees off cf still comes in perfectly
it is in fact the HC channels i have a problem with even though i am pointed to HC


my problem is with CHRO (CTV2) at HC

Hello Charette,

If Flavoie’s advice yields no results, here are some questions you may want to investigate:

1) Do you have any obstructions to HC or is it in plain line of site?
2) Could there be electronic interference from any gadgets in the household or from neighbours?
3) Is your antenna tilted vertically (pointing to the sky or to the ground)? I found that with a slight tilt upward (20-30 degrees) you may get worst of better reception.
4) Have you tried plugging the antenna to another TV in the household? I found that my second TV has a better tuner giving me much better reception results.
5) Are you using the good quality RG6 coaxial cables? Sometimes a kink in the wire can reduce gain

I'm kind of new at this so tread with caution.

good luck!

I went back on the roof last weekend to straighten my antenna. It was pointing at 30-45 degree angle upwards and was tilted sideways so that the corner of my CM 4220 was the highest point of the antenna. I was getting PBS from two different sources at regular intervals in the evening. I fixed the tilt and adjusted the vertical slant so that it is now parallel with the ground and pointing to the right of HC at channel 18 and 23 tower. PBS is now gone. The tuner reads a weak signal but too weak to lock in.

Does anyone know how I can easily add a slight vertical tilt upwards to a J mount? The J mount came with the CM 4220.

Thanks for any advice. I was thinking of jamming a small piece of hardwood between the antenna mount bracket and J mount.

As well, does anyone know how much of a difference a CM 7778 pre-amp will do to my reception? Here are my TV fools results:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8387a66b89a348

ashtonp and charettepa, I hope you understand that the CM4228 shown on Ken Nist's site is not the CM4228HD. It is a completely different earlier model that outperformed it in most ways.

charettepa, do you have an original CM4228 or is it the newer, different CM4228HD?

AnalogMig, you can go to a satellite shop and get just the tilt portion of a dish setup that bolts onto your j-mount. Here's an example in this photo:

http://www.digitalhome.ca/forum/album.php?albumid=375&pictureid=1673

and there are more ideas in the following thread: Tilting Antenna for Better Reception (http://www.digitalhome.ca/forum/showthread.php?t=106196&highlight=tilting+reception)

stampeder, please see my note at the end of my message http://www.digitalhome.ca/forum/showpost.php?p=1314926&postcount=1064. I haven't been able to find the equivalent chart for the CM4228HD. Have you seen one?

Yes, that antenna has been tested extensively in our Antenna Research & Development forum, so start with the following thread:

CM4228HD Hardware Hacks (http://www.digitalhome.ca/forum/showthread.php?t=103749)

We test antennas very thoroughly before they are put on the Antenna Chart! :)

analogmig,

The weather totally changed to cold over the last two days. That could have something to do with your loss of PBS(s).

I've given up on CHRO.
I'm in the Anderson/Mitch Owens area.
I don't receive it at all although it does pick up as a channel.

Actually waiting for a new antenna but I'm afraid the line of sight here is too low for the position of the transmitter. I'll see if the new antenna makes a difference.

CTV2 is the only channel not coming in at all now, even Global signal strength has improved to where it doesn't pixelate or cut out.

I have to say my wife and I are amazed at the reception quality we now receive for the other channels. Used to be an issue with snow, poor quality... but no more. Thank the gods for Digital.

Norman
Hey Refine,

It looks like you’re near my location. I'm in Riverside South. I get CHRO (CTV 2) no problem. You are maybe too close to the HC antenna. Looks like you're no more than 2 miles away. Maybe raising the angle on your antenna towards the sky at say 30 degrees or less towards Herbert's Corner would improve reception?

just a thought.

charettepa, all of what AnalogMig suggested makes sense. If you tilt a bit upward you may suffer a bit on the side for CF but it's hard to tell. Only you will be able to tell...

analogmig,

The weather totally changed to cold over the last two days. That could have something to do with your loss of PBS(s).
Hmmm. I did not know cold affected reception? I guess just about everything affects reception; clouds, air quality, position of the moon?

I'm going to experiment with this tonight. I'll “jerry rig” the antenna tonight and give it a 10-30 degree tilt towards the heavens. We’ll see if reception improves.

When the weather turns cold during the day, I believe you are less likely to get inversions that cause tropospheric ducts.

just wondering is cbc channel 4 acka (25 in disguise) having a lot of problems ?

CBOT 4.1 was fine for me this morning in Craig Henry.

AnalogMig, as discussed a couple of times earlier in this thread, CHCH is now, since Sept. 1 on RF 22 from the south (HC). Since WNPI (RF 23) is a distant weaker channel it could be suffering from adjacent channel interference now for you (there's also TVO on RF 24 from the north-CF, but should affect less if your antenna is directional).

For those with 8-bay antennas (4228, 8800, DB-8) potentially sufferring from adjacent channel interference from CHCH in their reception onf WNPI on 23, if your bearing to South Colton is 15 degrees or more away from Herberts Corners, I would suggest tweaking the direction of your antenna. There is a deep null in 8-bays at about 30 degrees, so by detuning your antenna away from Herberts Corners, you will increase the attenuation of 22 a lot more than you may decrease your reception on 23, and WNPI may pop through, because your tuner will be less desensitized by the large signal on 22.

The same trick will work for reception of WNYF 18 adjacent to City-tv on 17. However, in that cases, there is a lot less headroom in the WNYF signal, so losing even 1 dB of gain on the main log may hurt reception of 18 anyway.