I get signal strength, but no image ?!
 

Hi: I am just south of Montreal, Quebec. I can get channels 3.1 and 5.1 with a signal strength (as measure by my TV) of around 55db. When I switch to channel 22.1 (ABC) I see a signal strength of 69db, but no image. Any reason? Thanks!

Other digital channels
 

What about other digital channels ?

Other channels are ok.
 

Hi: I get all the canadian channels in Montreal ok. I can see the CBS and NBC channels from Platsburgh(NY) and Burlignton (VT), but ABC (22.1) I only see my TV showing a signal (diagnostic menu in the TV), but I get a black screen. Is my TV too "old" to decode this signal? Is like there is a carrier wave but no info...(?!)

Television reception.
 

Answer this question , straight out. Are you receiving and watching any DIGITAL ATSC CHANNELS NOW ? If the answer is Yes , give the Digital Channel Numbers and stations. Digital channels only , no Analog channels. What are you receiving the Digital ATSC Television Channels with ? A Digital Tv or a Digital Converter box ? If you have no Digital Tv or Digital Converter Box then say so clearly.

My setup
 

Currently I have a regular analog antenna (bunny ears) straight into my JVC HDTV. The antenna is in the second floor, looking straight south, ie: towards the transmitters.

The following channel I can see no problem:
WCAX-DT (Digital)
Channel: 22 (3.1)
Network: CBS
Maximum ERP: 443.000 kW
Coordinates: 44.525607 -72.815679


The following channel is the one that I see signal strength, but no image:
WVNY-DT (Digital)
Channel: 13 (22.1)
Network: ABC
Maximum ERP: 10.000 kW
Coordinates: 44.525885 -72.815401


Does this help?

No, there should not be any problem with signal decoding. Any receiver capable of decoding ATSC signals should be able to show something as long as it has a good signal to work with. The ATSC broadcast standards have not evolved to the point yet where there are incompatible legacy receivers.

Your problem is most likely a simple matter of not having a good enough signal to work with. If the receiver cannot lock on to the ATSC signal properly, it cannot decode the stream of digital data, and it won't have any picture to display.

This may mean that you need a better antenna setup to get this channel.



To better understand your signal situation, it would help if you could post a signal analysis report for your exact location. For help on how to do this, there's a brief guide to using the tool available here: http://forum.tvfool.com/showpost.php?p=3

You might be interested in this forum, Gus, it's the Burlington, Vt. AVS thread:

http://www.avsforum.com/avs-vb/showt...99530&page=127

You will have to go up or down the thread pages to find info on WVNY.

There has been some discussion about WVNY regarding problems, but my guess is that you being north of Montreal, an outside directional antenna might be advised to receive WVNY. WVNY is running 10 Kilowatts of power on VHF-hi RF channel 13. Here in Hudson Falls, N.Y., 91 miles from WVNY, it isn't strong enough for me to get a picture, but just strong enough to desense an Albany, N.Y. RF 13 station. I do get WCAX and WPTZ quite well at 91 miles out, but they are running hundreds of kilowatts.

WVNY-DT on channel 13 is very difficult to get in the Montreal area, for several reasons:

- WVNY_DT's signal has a null to the north -- both because it has to protect CKTM in Three Rivers, and because the antenna is located below and south of the summit of Mount Mansfield. It is only throwing about 1kW ERP towards Montreal, not the 10kW which is the maximum it throws (in another direction.)

- depending on where you are located in Montreal, you'll have severe adjacent channel interference from analog CFCF-TV 12 or co-channel interference from CKTM 13 Trois Rivieres.

- low power VHF-Hi is notoriously bad for penetrating small aperture windows, so you would need an outdoor antenna, usually a 10-element yagi, to get it. Check in the digitalhome.ca/forums for the Montreal area to see how other people do it. I don't think I've read of anyone getting WVNY with an indoor antenna in the Montreal area. Most people can't get it with an outdoor antenna, but those that do are using channel-cut yagis, or DBGH with NARODs (see the Antenna R&D section of digitalhome forums for an explanation of NAROD).

It's possible that things will get better in 17 months when 12 and 13 flash-cut to ATSC signals, since their power levels will then be down 15-20 dB.

Compare WVNY-DT's coverage to WCAX-DT's or WPTZ-DT's

The 'green area' (suitable for indoor TV reception) for WCAX extends well onto the island of Montreal, while the green area for WVNY barely crosses the border.

Gus, you didn't mention what kind of antenna that you are using, but it's a safe bet that a better antenna, one that has particularly good VHF-high-band gain, will go a long way to helping you. Many people in the Montreal area get good reception of the Burlington-Plattsburgh stations, even on the Island, but digital VHF stations broadcast with considerably less power than do their UHF digital counterparts. I suggest mounting a high-gain VHF-high-band plus UHF antenna on your roof, and use a rotator: you'll see all the Burlington-Plattsburgh stations as well as the Montreal stations. You should also see WFFF, the FOX station and the two PBS stations from VT-NY when using a good outdoor antenna. I would suggest looking for a Winegard HD-7696P and a rotator, or possibly an AntennasCraft HBU-44