Newbie question about ATI TV Tuner 650 OTA cable

blackrain

Golden Member
Feb 15, 2005
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Just got a Diamond ATI TV Wonder 650 Combo/Dual PCIE card. Anyway, it comes with this cable (or something very similar), which I plugged into the digital RF input:

http://cgi.ebay.com/ATI-FM-RADIO-AN...0214?IMSfp=TL100214122005r26430#ht_5362wt_939


ATSC signal was recognized. But why is this a cable? How am I supposed to arrange it? It is sitting on top my case and looks like a mess. What are three black loops at the ends of the cable? Is there some special way that I am supposed to set up this cable?

As a side note, some channels come in crystal clear while others come in very pixelated and jerky. What gives? Is this normal? Can anyone help a newbie get this TV Tuner set up correctly?

I am using windows media center 7 x64. Windows Update found my hardware and added the drivers. I haven't installed anything else.
 

Pederv

Golden Member
May 13, 2000
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It's a standard dipole antenna. I've used the loops for mounting the antenna, usually arranged so that the antenna forms a T. Dipoles are dirrectional but this can be offset a little by letting the upper part of the T sag down to a 45 degree angle.
 

mmntech

Lifer
Sep 20, 2007
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I have the same card. That cable is intended for receiving radio signals, which this tuner can do. You're supposed to hook it up to a proper ATSC antenna or a cable system. That antenna isn't powerful enough to get television broadcasts.
 

blackrain

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Feb 15, 2005
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Can someone give me an example of a good ATSC antenna that I can buy. Should I run up to Radio Shack? They are sometimes overpriced.

Pederv: Do you have a picture of your setup?
 

Paperdoc

Platinum Member
Aug 17, 2006
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This is in the realm of TV and FM radio antenna design.

The unit you show is a simple type of dipole antenna made from a length of 300-ohm twin-lead antenna wire, and designed mainly for use for FM radio. Ideally you stretch it out as Pederv says, with the two arms horizontal and the center line running down to plug into the antenna input of the card.You can hook the ends and center to pins or nails or something, or fasten it to a long stick and mount the stick somehow. It is directional - it picks up best PERPENDICULAR to the long 2-arm direction - that is, it is worst ALONG the stretched out arms.

This antenna is sized for radio waves in the FM radio band, which is just above the frequency range for the old VHF-Low (channels 2 through 6) analog TV band. So it will pick up those low-channel stations not too bad, but it will be poorer for the VHF-Hi band (channels 7 through 13) and probably much worse for the old UHF range (channels 14 through 69).

Now, that antenna will work fine for local FM radio. The dilemma you have for TV, though, is that all TV in the USA switched to digital, and MOST of them also switched to the UHF frequency band as they did that. SO, this antenna is likely to be very poor for local OTA TV unless your preferred station happens to be in the channel 2 through 6 range. "Pixelated and jerky" is what you get with weak digital TV signals. Analog weak signals looked like a bad picture with "snow" and odd colors. Digital weak signal just makes the receiver freeze on the last good signal it gets until it gets a good one again.

If you want reasonable reception from OTA transmitters in your area, check the channels they are on for starters. I expect some or most will by above channel 14. For those you can buy many different small antennas designed for indoor use. They are small because the wavelengths are short. They are widely available in electronics shops, TV sales shops, big-box stores, etc. The problem is not finding some. It is deciphering which ones are any good, because they ALL are the best in the world! If you can, search the web a bit for actual performance test-based reviews of antennas to help identify the best in your price range. More expensive and complex, and usually larger, will usually get you a better signal, but you won't want the biggest and best for average home use. If you really want to go techie and "roll your own", look on the web for Gray-Hoverman antenna design developments.

Don't forget, IF you have cable TV service in your place, there are lots of channels there. Many will be digital signals. Some of those will be HD, some will be only old standard-TV quality. Depending on your local service, there may be still several analog TV channels on your cable. I'm sure your card could tune in those if you want to.

Check your card's manual carefully. There are various designs around. Some, for example, have two tuners inside and two antenna input connectors. But the way they work is that one connector is associated with only one tuner capable of handling FM radio and OTA digital TV done by the ATSC coding system, while the other connector / tuner set handles only digital TV with Clear QAM encoding on cable systems. Some are arranged differently with all tuners able to handle all tasks. So read your manual and make sure you connect whatever antenna / signal source you have to the correct input.
 
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Pederv

Golden Member
May 13, 2000
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Can someone give me an example of a good ATSC antenna that I can buy. Should I run up to Radio Shack? They are sometimes overpriced.

Pederv: Do you have a picture of your setup?

I would suggest getting an antenna that has a built in amplifier. Most of the PC tuner cards on the market have little or no AGC (Automatic Gain Control) so the channels with strong OTA signals are the only ones that won't break up.

My setup is a little off from the standard setup. I'm using the Comcast signal to my QAM tuner and the composite output from the cable box to feed the S-video of the tuner card, then I'm also using the antenna that you showed to feed the analog/FM tuner. Most of the time I'm using the S-video input on my tuner card and the cable box to change channels.

The dipole antenna is on the wall behind my desk and for the most part isn't visible. Taking a picture of my setup would require pulling everything away from the wall.
 

Paperdoc

Platinum Member
Aug 17, 2006
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IF you are trying to pick up weak TV signals, be careful on antenna selection. A small antenna with a built-in amp is NOT going to do it. The amp only increases the strength of ALL its input signal, including the noise part, so it does nothing to improve signal-to-noise ratio of the signal delivered to your tuner. For a weak incoming signal, the only real improvement is an antenna design that gathers more signal in the first place for better S/N, and that is almost always a larger antenna.

You also must pay attention to what frequency range the station is broadcasting; your best guide here is the channel number. Most US stations now are using channels 14 through 69, the old UHF band. Antennas for that are relatively common, and range from small set-top units to larger arrays like the exterior-mounted one referenced by Modelworks. A few stations are still using channels 7 through 13 (the old VHF-HI band) which is at lower frequency than the UHF band, but there a several broad-band antenna designs able to cover both frequency regions well. However, if you are trying to get improved reception in the range of channels 2 through 6 (the old VHF-LO band) or FM radio, they are at MUCH lower frequencies (and hence need much larger antenna elements) and there are not a lot of antennas that cover ALL of those ranges well. In selecting an antenna, look closely at the claimed "gain" numbers. In fact, they are different for different ranges of frequency (channels), and some makers prefer to tell you only their best number on the low UHF band, even when they claim good performance on all bands. Some will actually quote the different Gain values for several channels over all the bands they claim they do well on.

Amplifiers certainly have their place, and it's AFTER you ensure you have the best signal you can get. For example, to get a good S/N I selected a broad-band large exterior-type antenna recently, but mounted it in my attic, not on the roof. I wanted to ensure its signal would reach the several TV's (through a splitter and many cables to different house areas) at good strength. So I mounted a broad-band amplifier right at the antenna to boost the total signal before it is sent down the cables and distribution network. This means also that it is boosted BEFORE it can pick up additional noise along the cable system. So you start by picking up the best signal you can and need, then amplify it right away before sending it along a distribution system that will weaken it.

By the way, as I've proven to myself, you can get too much amplification if you are over-enthused. I once had poor recepti0on at my computer's tuner that I traced to using a too-powerful amp in the line feeding it - the signal was swamping the input stages of the tuner. A smaller amp in the line solved that.