splitting an HD signal

[powerdog]

I have our main HDTV connected to TiVo, which is connected to a rooftop antenna. The antenna gets a strong signal with the channels we care about (mostly PBS). Now I'm thinking about adding a second, smaller HDTV in another room. The question is:

Use an indoor antenna for the new TV?
Or split the rooftop coax and add about 15 ft. of cable from the splitter to the 2nd TV.

I'm wondering if a splitter would weaken the signal to both TVs, so that SD channels look worse and marginal HD channels don't come in at all. If so, would a signal amplifier be of any use?

BTW, I'm in the red zone for the channel I use most -- PBS HD.

[hdtvlabs]

I would go for a splitter as a first choice.

Indeed, RF signal is attenuated when passing through a splitter. This attenuation is specified as "insertion loss" of a splitter, and usually can be found in the manufacturer specs. A typical VHF/UHF splitter insertion loss is about 3-4 dB, meaning that the signal power is cut by nearly 50%-60%. It may seem a lot, but in the RF world 3-4 dB is not that much. An indoor antenna is likely to deliver a signal that is substantially weaker than the after-split signal, in the red zone an indoor antenna might not be usable at all.

While it is not possible to know in advance whether the 3dB splitter loss will kill your marginal HDTV channels, I would try a splitter first. Splitters are very cheap, you can get one for under $1 price, so why not try it before buying an indoor antenna?

When picking a splitter pay attention to the following:

- Frequencies. Make sure you buy a splitter that supports the range of 50 Mhz - 900 Mhz. Satellite video splitters may not support these freqs and won't work for you

- Impedance. Typically it is 75 Ohm and should match the impedance of your coax cable. There are also 300 Ohm wires and splitters on the TV supplies market. You can distinguish between different impedance cables by connector type.

- Gold plated connectors for improved performance

- Combiner/splitter dual operation. The same device can work as a combiner or a splitter. Nice to have.

You may want to check this one.
It is very simple and cheap, but works fine in most cases.

Good Luck

[powerdog]

24 cents?! That is cheap.

Is this one a scam? --

http://www.amazon.com/Monster-TGHZ-2RF-Gigahertz-Splitters-Satellite/dp/B00003CWG2/ref=pd_bbs_10?ie=UTF8&s=electronics&qid=1208968984&sr=8-10

I see it got good reviews, even from people who don't think much of Monster.

BTW, does it make any difference if only one TV is on at a time?

[hdtvlabs]

Is this one a scam? --

http://www.amazon.com/Monster-TGHZ-2RF- ... 84&sr=8-10"

Ok, if you want the highest tier splitter with internal impedance matching network you can buy the one you found on Amazon. It will probably achieve a lower signal power loss, however if you use a standard 75 ohm coax and a commercial grade antenna the impedance matching is less important. It also works in a wider frequency range, and is suitable for satellite tv as well.

Even then, at $40 it is ridiculously overpriced. You can take it for $18 here http://www.bhphotovideo.com/bnh/control ... 174&is=REG

But you know what?! I will not be surprised if the 24 cent splitter works just as well.

BTW, does it make any difference if only one TV is on at a time?

Should make no difference if the impedances are well matched. In reality, minor impact possible.

[powerdog]

I wonder how many of the 5-star Amazon reviews would survive a double-blind study with the 18 cent alternative for comparison.

[dynamic]

Likely not many. I sometimes have to wonder about so many 5 star ratings over there anyway. Don't get me wrong, I've bought plenty there. I don't buy the ratings system they have though. Same situation on overstock.

[Kim]

I agree. Have you read the reviews from the people on Amazon? Sometimes, they will give a really low rating because of the shipping experience. That has nothing to do with the item they are rating! Or they will say that they just took the thing out of the box and it is great. You can't really trust those ratings. But, reading the reviews can sometimes be helpful.

[powerdog]

I especially love the complaints on Amazon from people who buy without understanding the product or their needs. ("This 2-slice toaster just melted my DVD!")

OTOH, there are some products that are reviewed almost nowhere else.

[Bill]

Yeah, I think Amazon can be useful but it definitely cannot be the only resource you use.

[dynamic]

It's a shame too, because those systems were put into place to be helpful. I work online as well, so I know that a product can be rated badly because of bad shipping services. I'm not trying to derail the topic too badly though, so I'll just suffice it to say that something I shipped sat in the UPS office for a week. It actually should have been to its destination the next day.....