1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Antenna amplifier

Discussion in 'TiVo Bolt DVR/Streamer' started by LekaLeka, Jul 11, 2018.

  1. LekaLeka

    LekaLeka New Member

    Mar 5, 2009
    Any recommendations on an antenna amplifier or booster that works well with the Bolt?
  2. jrtroo

    jrtroo Chill- its just TV

    Feb 4, 2008
    Why do you think you need this? I ask as many look to these when they have a bad signal, and boosting a bad signal gets a stronger bad signal, a frustrating experience.
  3. JoeKustra

    JoeKustra in the other Alabama TCF Club

    Dec 7, 2012
    Ashland, PA...
  4. LekaLeka

    LekaLeka New Member

    Mar 5, 2009
    In most cases ota on a bolt requires this. I loose channels when I connect my antenna onto the Bolt. Confirmed with Tivo that this is what I need.
  5. Saturn_V

    Saturn_V Now with flavor!

    Jun 1, 2007
    Antenna Amplifiers don't really improve your reception. They help reduce signal loss over longer runs of cable ( > 6 ft) and/or reducing loss through signal splitters.

    Try relocating your antenna, get it as high as you can. The higher it's mounted, the better it works. Mine is mounted on the upper corner of a window facing the broadcast towers- there's an amp- but the run is 12 ft and it splits to a Roamio and HD HomeRun network tuner.
  6. LekaLeka

    LekaLeka New Member

    Mar 5, 2009
    I have spoken to Tivo and they said I need an amplifier or signal booster. Thus is due to the design of the Bolt. I loose channels when connected straight to the Bolt and not to the tv.
  7. jrtroo

    jrtroo Chill- its just TV

    Feb 4, 2008
    Unless the run has a lot of splitters or is of a great distance, I'm skeptical about this helping. I suppose if your connectors are leaking signal that it could also help. I'd go for a better antenna location first, then the connectors next, and cable last.

    How far is the run from the antenna to the bolt?

    I'm thinking the csr script may have suggestedthis for a cable installation.

    Good luck.
    Last edited: Jul 12, 2018
  8. tapokata

    tapokata Active Member

    Apr 26, 2017
    Sacramento, CA
    A pre-amplifier located by the antenna will help to make up for signal loss due to long coax runs, multiple splitters, or other insertions that can bleed off the signal strength before it arrives at the tuner. It's helpful if the signals are borderline, but may not be necessary at your location.

    Before you decide that an amplifier is needed, run a TVfool.com report for your address, and look at the column for the noise margins for the stations you are trying to tune in- anything below 20 dB may benefit from the use of a preamp. A noise margin greater than 60dB will likely be overpowered by the use of a preamplifier.

    You can review and estimate the amount of signal loss at your location by making a few notes and creating a coax insertion loss budget. Make a list, starting with the antenna. Add the average gain for the antenna on channel (that should be in the antenna specs). That can vary by channel and antenna design, but an average is a good starting point. That will be a positive dB value. From here on out, everything else is a loss from that number. Subtract 2.5 db for the balun- that's the connection for the matching transformer that converts the twin downloads from the antenna to coax. List any filters or straight (non-split) connectors in the path from the antenna to the Bolt. A rule of thumb is to subtract 1 dB for any filter (lightning arrestor, LTE filter, etc) for any filter where the insertion loss is not known. Subtract another 0.5 db loss for each straight connector, or wall jack. Estimate the total cable length from the antenna to the Bolt- for every 10 feet, subtract 0.6 dB. For each splitter that the line passes through, you'll need to account for the insertion loss for the input-and-output connection on the splitter. A two way splitter will lose about 3.8 dB per port. A three way splitter will lose about 6 dB per port. A four way splitter will lose about 8 dB per port. You're only subtracting for the lead from the antenna to the Bolt, not the other ports. Tally the losses, which will be slightly reduced by the antenna gain, and that will give you an insertion loss budget. Subtract another 10 dB for any unknown variables as a safety margin. Now, compare that net number to the Noise Margin number for the TV Fool report. If you have a loss budget of -25 dB, anything with a noise margin of 25dB or below will likely not be tunable without a preamp.

    In-line system amplifiers are good choices in CABLE TV environments, where the signal strength from the cable provided is diminished by multiple splitters, etc. Line amplifiers have high noise factors, meaning the introduce or amplify unwanted noise at the same time they amplify the signal. Pre-amplifiers have noise factors as well, and in some cases a cheap amplifier will introduce nearly as much noise as it does signal amplification.

    The Bolt has a built in RF gain circuitry. What are the reported signal numbers (these numbers are relative to each other) when you review the diagnostic screens? The default "gain applied" number on the signal gauge is 72 dB- the Bolt's circuitry either attempt to amplify the signal to that level, or attenuates a strong signal down (when it can) to that number. If you are getting those numbers, you likely don't need an amp.

    As others have wisely noted, antenna placement is a crucial factor. Antennas like fresh air, and the higher up, the better. That said, if the line of sight direction points the antenna through nearby foliage (trees, leaves), that can create multi path issues which will briefly break up the signal reception (you'll see block patches, hesitations, drop-outs), and no amplifier can correct for a signal that is getting to the antenna for that reason. Blowing leaves on a tree are death to a UHF signal. Antennas in an attic will be affected by the materials used in the roof. Indoor antennas may work wonderfully, or not at all (I live in a lathe and plaster house, with a stucco over wire mesh exterior. It's like living in a Faraday cage for RF signals).

    Good luck.
    dfreybur and ClearToLand like this.
  9. aaronwt

    aaronwt UHD Addict

    Jan 31, 2002
    I've been using a 28dB preamp on my two outdoor Square Shooter Antennas for fourteen years now. It was the only way I could reliably get the local DC signals from my location. EVen though one of those Antenna websites said I should be fine. My cable run is only around forty feet before hitting my Bolts.

    Initially I tried a 19dB preamp which wasn't enough for my situation. But once I hooked up the 29dB pre-amp, it made a huge difference with my two combined Square Shooters.

    EDIT: After looking at my posts from 2004 at AVS, it looks like I got the 29dB amp by mistake. So I initially used that. But when I swapped it out for the 19dB pre-amp, I lost a bunch of channels. So I put the 29dB pre-amp back in place. I'm still amazed that all that stuff is still working great after 14 years outside, in the elements.

    I've been able to receive the same OTA channels with my HR-250 TiVos from 2004, as from my Series 3 TiVos from 2006, as from my Premieres from 2010, as from my Roamios from 2013 through today, and the same as from my Bolts in 2015. Although now I only have two Bolts and both are using cable while my Roamio is being used for OTA.
    Last edited: Jul 12, 2018
    krkaufman and kpeters59 like this.
  10. V7Goose

    V7Goose OTA ONLY and Loving It!

    May 28, 2005
    New Mexico...
    This statement is COMPLETE BS. I realize that you THINK you got real good information directly from TiVo on this, but those morons have absolutely no clue on any subject at all. They have even told people that their OTA Bolt must show a signal over 72% to work, which is not only impossible (due to the internal AGC circuit), but the Bolt will have perfect reception with any CLEAN signal above 45%.

    The statement that "In most cases ota on a bolt requires this" is so wrong and uninformed that it almost does not deserve a response. Here is just one real-world example:

    I live in a remote mountain area served only by low-power translator stations, and my house is down in a hollow behind a high ridge without any line-of-site to the transmitters. I have to have an amplifier on my antenna to receive ANY signal at all on ANY device. With the amp in place, both of my Bolts receive identical signals as all three of my TVs, showing the Bolt tuners are just as good. In contrast to my location, I set up a Bolt for a friend who has a house about 20 miles from the towers with a clear line-of-site to them, and even though those translators are sending out less than 1KW (one of them is only 0.1 KW), he gets a perfect signal without an amp.

    You personally may or may not need an amplifier, but you have provided absolutely no information to indicate that in any way. We cannot provide any meaningful help until you do.
  11. CIR-Engineering

    CIR-Engineering Video Calibration & Electronics Repair Engineer

    Sep 24, 2017
    Chicago USA...
    I've always had my antenna high on the roof and knew there were stations further away that I should theoretically be able to get so I got a bigger antenna which did not help, and then a pre-amp which also did not help. But since I didn't get any more stations with the new setup I moved my antenna into the attic. Reception was not as good as outside so I added the pre-amp and wallah, good reception without any drops with all the same channels that I was getting on the roof. I am using the Winegard Boost XT (LNA-200). They have a great SNR and are inexpensive.

    Winegard Boost XT 20dB Pre-Amp for Outdoor HDTV Antennas (LNA-200) from Solid Signal



    krkaufman and aaronwt like this.
  12. LarryAtHome

    LarryAtHome Member

    Feb 18, 2008
    When looking for an amplifier, you can get a pre-amplifier that is to be mounted near the antenna and amplifies the signal before it has any loss travelling down the cable. There are also distribution amplifiers that amplify and split the signal. These overcome losses due to splitting the signal. You need a good signal first to amplify and then split. If the signal is too low, then amplifying and splitting will introduce a lot of noise, and you will not have a good signal to the BOLT. Look for very low noise factors in any amplifier you may get. If some channels are very strong in your area, an amplifier may overload due to the strong channels. Amplifiers amplify all the channels and not just the channel you are watching or recording. Just like too little of a signal causes problems, too much also causes problems. Moving, raising, or changing the location of the antenna may also help. You need to get a good signal at the antenna first, then if it is too low, and you have it in the best location, an amplifier may help, but not always. The signal the bolt requires may need to be a little higher than some tv's as the signal is split inside the bolt to send it to all the tuners. There is an automatic gain control circuit which should take care of this unless the signal is just too low. It can be a lot of trial and error to find out what will work for you, and then as the seasons change, your antenna reception will change which can cause more issues. What works today may not work tomorrow…...

Share This Page