RF Analog DA for Digital?

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oneworthyfellow
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RF Analog DA for Digital?

Post by oneworthyfellow » Tue Jan 29, 2013 3:32 pm

It must be Superbowl time for a question like this, but here goes:
Will a distribution amplifer made for analog TV boost digital TV signels? You know the one -- made by Tandy about 10 years ago for retail sale to consumers, with 75 ohm co-ax input from TV antenna, and feeds 4-5 co-ax outputs. It's a bit of a run from the roof to the basement, and already have a 1-to-3 splitter in place, so the ol' analog DA would fit the bill IF it will work, but it's a bit of a hassle to hook up for the try-and-see approach. Figured it would be better to ask the experts . . .
Thanks for your help! :D

w9wi
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Re: Analog DA for Digital?

Post by w9wi » Tue Jan 29, 2013 5:19 pm

Yep. There's really nothing in those amplifiers that's specific to analog or digital.

How far are you from your local stations' towers? Digital signals can be *too strong* -- if you're within 5-10 miles of the towers, your amplifier or TV may overload, causing some channels to not work.
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oneworthyfellow
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Re: Analog DA for Digital?

Post by oneworthyfellow » Tue Jan 29, 2013 8:14 pm

Thanks, Doug!

I'm about 20 miles from the transmitter site, so I'll fire up the ol' DA for the big game. Thanks again for your answer. :D

Kelly
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Re: Analog DA for Digital?

Post by Kelly » Wed Jan 30, 2013 9:37 am

My only suggestion is to check the label of the amp to determine the pass frequency. Some of those older Rat Shack amps were designed for primarily operation in the VHF band. If the label says top end stops at 450Mhz (which is in reality closer to 360Mhz), you may not be able to amplify certain higher UHF DTV channels.
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Dave Loudin
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Analog DA for Digital?

Post by Dave Loudin » Thu Jan 31, 2013 6:36 am

So, without the DA, reception is spotty or nonexistent? Another thing about Rat Shak amps - high noise figures. If that DA has a higher noise figure than your tuner, then it will not help at all.

You sure you are looking for the right RF channel and that your antenna is actually designed for that band?
What's that do....?

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NECRAT
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Re: RF Analog DA for Digital?

Post by NECRAT » Thu Jan 31, 2013 3:45 pm

I don't have much more to add here, other than I changed the title of the thread slightly to indicate that you were talking RF and not video.
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KPJL FM
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Re: RF Analog DA for Digital?

Post by KPJL FM » Fri Feb 01, 2013 8:55 am

I had to pull my old Rat-Shack 1 in 4 out amp, it was causing intermods on low VHF. Might be the power supply, but I was rewiring anyway, so I put it aside. A standard 10db gain amp after the first splitter works well. If you add an amp and some channels get worse, try putting a 3db pad on the input to the amp. that helps when the input signal is too strong, causing the amp to overload.
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oneworthyfellow
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Re: RF Analog DA for Digital?

Post by oneworthyfellow » Fri Feb 01, 2013 10:01 am

Thanks to all for your help and useful comments. The Radio Shack DA was installed to take the place of a 1-to-4 splitter and so far is working like a champ. Even found the long-wished for virtual channel 9 from Windsor, Ontario -- now that the NHL is playing again -- looking forward to Hockey Night in Canada (my antenna is in a suburb near Detroit).
Thanks again. :D

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Deep Thought
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Re: RF Analog DA for Digital?

Post by Deep Thought » Fri Feb 01, 2013 12:04 pm

An amplified splitter is usually a different animal than an inline RF amp, so it'll have less of a tendency to overload and spray crap all over the band. But the best indication that you did it right is that is working. 8) :mrgreen:

Enjoy the game. We'll be watching the Puppy Bowl... :lol:
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Kelly
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Re: RF Analog DA for Digital?

Post by Kelly » Fri Feb 01, 2013 4:22 pm

GO RAVENS!
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