OTA Preamp

jerryjulian

Member
Original poster
Nov 8, 2008
9
0
Can I use a preamp (signal booster) on my over the air HD antenna? I have an HD DB8 antenna with a a Holland DPD2 splitter with both Dish and OTA antenna input on the roof and another Holland splitter at the receiver for both SAT and OTA signals into the receivers. It works, but 2 stations have too low signal strength. My question is whether I can use a a signal booster (like a Motorola 484095-001-00 at the PVR or an on the mast booster like a PA-18). Both have 12V power supplies. This was too technical for telephone tech support.

Regards,
Jerry Julian
 
I can't answer the questions about the xyz123 model amps per se, but it is always best to have the amp as close to the antenna and as far away from the receiver as possible.

It's a rule of thumb. It has to do with raising the noise floor.
 
Those DPD2s aren't splitters, they are diplexers. The DC pass on those is strictly to the satellite side so applying a power inserter by the PVR wouldn't result in that power getting to the antenna pre-amp. You don't want to amp the signal by the receiver because amplifiers don't work well if the signal is already garbage. Garbage in = Garbage out (amplified). Instead, put a pre-amp at the antenna and run that pre-amp in to a 2 port single port power pass splitter. Install the power inserter for the pre-amp in another room that doesn't have satellite or that doesn't have TV altogether such as the attic, a spare room, etc. Then run that line to the power pass side of the splitter. Run a line from the non power passing side of the splitter to your DPD2 by the dish.

Another option is to run a separate antenna line to the PVR location. This will allow you to amp the antenna without a power pass splitter and without the insertion loss of diplexers. The result is a cleaner signal, which is important for digital OTA. You can have a real weak OTA signal on digital, as long as its a real clean signal. Furthermore, check your antenna pointing for possible sources of multi-path distortion such as large buildings, mountains, etc. Another possibility is to choose an antenna that has a very narrow beamwidth if all your TV station towers are pretty much in the same direction.
 
Thanks much for your informed reply! I guess the second option (separate antenna line with mast preamp) would be the easiest....except having to drill another hole in the outside wall. Can I leave the diplexers in place, since he cut my Dish coax to install them?t
 
Good, that makes things easier. Whhat do you think about leaving the diplexers in place (just remove the OTA line), since he cut my dish coax to insert them?
 
Why can't the power part of the preamp be next to the TV?

He can do that, but he can't do that with diplexers as the diplexers don't route power to the VHF/UHF ports so the power would never get to the antenna through the sat wire. Instead, he can run a separate cable.

You can leave the diplexers in place.

As far as a hole from outside, drill a 3/8" hole and angle the hole slightly upwards when drilling from the outside. Put the wire through and caulk the hole. Make sure the wire runs down from the hole before running back up. That will allow any rain that collects on the wire to drain away from the hole. Use RG6 coax as there is less signal loss than RG59. I have also found that the wire will go through the hole easier if you strip off about 5 inches of wire, leaving just a center conductor to put through the hole. Don't push hard on the wire, just gently "feel" inside your hole for the other opening and it should go through slick when you find it. Then go inside and pull the rest of your wire through or have a helper do so from inside.
 
Just leave it as is

or I could replace them with a double female connector.

Just leave the diplexer inline and remove the OTA line. Then if you have them put plastic coax covers on it. The thing about the inline barrel connectors is they come in different quality. Most are designed to do cable just fine but not as many that do sat as well.
 
I don't think a DB8 is a powered antenna. Unless I'm missing something all he wants is a power booster and I'd guess the booster would be 'directional" like a DPP 44 switch power inserter, for example.

So as long as the booster is 'facing' away from the diplexer, I don't see why it would be a problem.

But again, if I'm not seeing this correctly, feel free to enlighten me.
 
I don't think a DB8 is a powered antenna. Unless I'm missing something all he wants is a power booster and I'd guess the booster would be 'directional" like a DPP 44 switch power inserter, for example.

So as long as the booster is 'facing' away from the diplexer, I don't see why it would be a problem.

But again, if I'm not seeing this correctly, feel free to enlighten me.
He's looking at a preamp and that is powered and the voltage runs up the coax to the antenna mounted preamp. If you can't get the voltage to the preamp it doesn't work.
 
I gotcha, no,an antenna mounted preamp won't work with the DPD2.

But he also mentioned a Motorola 484095-001-00 which, while perhaps being overkill and steve4810's noise floor concerns not-withstanding) looks like something he could place behind the reciever after the last diplexer.

But I agree, a dedicated cable would probably be the best solution.
 
You guys have convinced me to go with a dedicated OTA cable with a mast preamp. I will look for some plastic covers to cap the DPD2 diplexers.

I really appreciate all the advice!!!
 
But he also mentioned a Motorola 484095-001-00 which, while perhaps being overkill and steve4810's noise floor concerns not-withstanding) looks like something he could place behind the reciever after the last diplexer.

Garbage in = garbage out. It's better to push the signal than to try and pull it. Amplifiers don't make a distinction between noise and desired signal. It tries to amp it all to a consistent level. So noise is then increased, often at a 3 to 1 ratio. A high signal-to-noise ratio is needed to ensure a clean digital signal.
 
You would just need to add another power inserter upstream from the inside preamp.

But though some may argue with me I still think you will be ill-served by putting an preamp next to the receiver. The first part of the receiver CONTAINS a preamp. And which do you think is a more sophisticated device: the blister-pack amp or the guts of a several hundred dollar DVR?

You don't want to pile up preamps. Just think about the gain you expect to get with the two preamps you are thinking about and buy a better single one of that gain and put it on the mast.
 
Below is what I received from Dish "Tech Support". Any idea what ground she is talking about? I have a VIP 622 receiver.

RE: Technical Support, 9512401368 Dear Jerry Julian,

Thank you for your email. We appreciate your inquiry and are happy to assist you. We would not suggest any type of signal booster at the PVR. It would be acceptable to use an on the mast booster but you will need to make sure that the line is run through the system grounding in order to protect the hard drive in the dish receiver. I hope that I was able to sufficiently answer your question.

Your business is greatly appreciated and we thank you for allowing us to be of assistance to you. If you have further questions you can respond to this e-mail or access our online technical support at the following link
A Technical Service Representative is available via live chat 24 hours a day, 7 days per week regarding your concerns. Please click the following link to use this option.
Thank you,
Michelle S.
DISH Network Technical E-care
** Please include all previous correspondence when replying. **
-----original message-----

_____________________________________________
From: jerryj3178@aol.com [mailto:jerryj3178@aol.com]
Sent: Saturday, November 08, 2008 4:00 PM
To: Tech
Subject: Technical Support, 9512401368

Can I use a preamp (signal booster) on my over the air HD antenna? I have an HD DB8 antenna with a a Holland DPD2 splitter with both Dish and OTA antenna input on the roof and another Holland splitter at the receiver for both SAT and OTA signals into the receivers. It works, but 2 stations have too low signal strength. My question is whether I can use a a signal booster (like a Motorola 484095-001-00 at the PVR or an on the mast booster like a PA-18). Both have 12V power supplies. This was too technical for telephone tech support.
Regards,
Jerry Julian
 
She is recommending the same thing as those above: put an amp as close to the antenna as possible. It's not clear to me either what ground she's talking about. But I suspect she is trying to tell you to ground your mast and antenna properly (for safety in thunderstorms).

Incidentally, I just added a 10dB distribution amp at my DVR, which is not where everybody else is suggesting we put it. I claim it helped, even though not optimal placement. I'll move it into my attic as soon as I find some power to energize it!
 
I think she is referring to the ground block, which usually has more than one feed-thru. So you could put Dish on one and the antenna on the other. While it will not withstand a lightning strike it will reduce the likelihood of differential static buildup ruining your receiver.

Make sure the 10 dB amp is 10 dB to each outlet, I have a 4-way, and it does help as I am 49 miles from the towers, LOS from under the deck. Then again, I diplex in 2 722s, potentially 4 channels--60 62 64 66--along with the OTA (ATSC and NTSC for now) for distribution to the 722s, a 622, and 2 TVs via 3- and 4-way splitters.

Note all amplifiers may fail to help if you have nearby radio or cell or other TV towers or an airport, etc., as they may overload the amp or its load.

-Ken
 
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