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12v Digital TV Signal Amplifier.


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There are many factors that can effect TV reception and some can be controlled while others can not.

To get better digital TV reception or to improve your current digital reception/signal may be a simple task or it may require a complete antenna system overhaul.

There are a few things that should be understood.

There are no magic antennas using breakthrough technology. A lot of what you'll read as you do your research is simple hype. There's no such thing as a 150 mile antenna or a thin indoor antenna that works as good as a quality outdoor antenna.

Better digital TV reception starts with the antenna but it's the entire antenna system that creates outstanding digital reception. It all matters starting at the antenna and getting the signal to the TV.

As I said, it does start with the antenna. If the antenna is not receiving an acceptable digital signal then no amount of signal amplification will improve the reception. You can't amplify a signal into existence if the antenna is not receiving it with sufficient strength. On the other hand the antenna may be getting a good signal but because of improper signal amplification or system layout the signal never reaches the TV. Or the antenna and amplification are correct but the coax cable wiring configuration is incorrect. In some areas you can connect a coat hanger to the TV and get reasonably good reception but if you are in one of those areas you probably wouldn't be reading this page.

Using the proper TV antenna for better digital TV reception.

The antenna must be capable of receiving the digital signal at a sufficient level of strength and quality to maintain consistent adequate signal strength. No amount of signal amplification can change this fact.

The antenna must be installed at a location that allows the signal to reach the antenna. If the antenna is mounted in the attic you may have to relocate it outside. If it is installed low to the ground you may have to relocate it higher in the air. Be safe seek professional help if necessary. In weak signal areas TV antennas perform best mounted outside above the roof line of your home.

You must have the proper TV antenna to receive the channel frequencies in your area. TV signals are divided into two main categories VHF channels 2-13 and UHF channels 14-69. Leading up to the analog shutdown date of June 12, 09 nearly all digital signals were broadcast on the UHF band. UHF antenna design can be much smaller than antennas capable of receiving both VHF and UHF signals. Some antenna dealers/manufacturers took advantage of the consumers desire for a smaller antenna and sold smaller UHF antennas as HDTV antennas. There's no such thing as an HDTV antenna.

If you have a couple of channels that won't come in you may have a UHF antenna and it may not be capable of receiving VHF signal. View UHF antennas.

What type of TV antenna do I need? VHF? UHF? To determine what channels are UHF and what channels are VHF visit the Digital TV Antenna Selector. The stations in your area will be listed as Lo-V (2-6) Hi-V (7-13) and UHF (14-51). Unlike in the old analog days the actual tuner display number that appears on the TV screen may not be the same as the real broadcast channel the station is using to broadcast the signal. For an example channel 2.1 may now actual broadcast their digital signal on a UHF channel. While channel 63.1 may broadcast on channel 26. The channel number referred to as the RF channel is the broadcast frequency. See: real vs. virtual channels. As of June 12, 09 no full powered TV station in the U.S. broadcasts a signal above RF channel 51. Channels 52 - 69 are no longer in use for TV broadcasting. Your TV tuner may display a channel number above 51 but the actual RF broadcast frequency will be 51 or lower. The channel number the tuner displays reflects the old analog number and is not necessarily the channel used to broadcast the signal. Visit the antenna selector link above to determine the channel frequencies in use in your area. Most antenna manufacturers have not fine tuned their antennas to accommodate the new frequencies in use. Fine tuning the antenna to meet today's frequencies will improve performance. Both the EZ HD and the HD Stacker antennas are up to date.

Better digital TV reception through signal amplification.

The antenna you have may be receiving a sufficient digital signal but the signal from the antenna may not getting to the TV with sufficient strength to produce satisfactory reception.

This is caused by one of the following:

  • Insufficient or no signal amplification
  • Improper location of the signal amplifier within the system
  • Inferior or damaged coax cable and or connector fittings
  • Improper cabling configuration (applies mainly to multiple TV systems)
  • Improper use or location of signal splitters installed within the system.

For each foot of coax cable a signal must travel a little signal quality is lost. Notice I used signal quality and not signal strength. The quality of a signal is just as important as its strength. The minute the signal leaves the antenna it begins to degrade. The solution to this is a quality preamplifier installed on the mast pipe near the antenna. Installing a mast mounted preamplifier near the antenna is best in moderate to weak signal areas. In strong signal areas a mast mounted preamplifier should not be needed. The amount of signal amplification required is determine by the signal strength of the incoming signals and the system configuration itself. OurDigital TV Antenna Selector will suggest the proper amplification based on your particular needs. Proper signal amplification may be the key to improve your digital reception.

Signal amplifier's have two important specifications. The amount of signal amplification provided by the unit and the signal to noise ratio. Both of these are measured in dB. Noise is any signal interference that is not related to the TV signal. If the level of the noise over shadows the TV signal from the broadcaster the digital signal will drop out no matter how strong the TV signal is. Some noise cannot be avoided but that doesn't mean you have to add more noise than necessary with the amplifier. You can get better/improved digital TV reception using amplifiers with lower noise level ratings. Any noise figure rated 3 dB or lower is excellent.

Coax cable can help obtain better digital TV reception

The TV signal will travel miles to reach your antenna don't let the last 100 feet ruin your TV reception and that's just what coax cable can do. The coax cable transfers the TV signal from the antenna to your TV. RG 6 cable is better then RG 59. Solid copper coax cable is better then copper clad (steel wire coated with copper). Don't coil the cable, excess cable is unnecessary signal loss. Replacing inferior or damaged coax cable can improve digital reception.

Configure your antenna system for better digital TV reception.

If the antenna supplies signal to 1 TV run a single coax cable line from the antenna to the TV and remove all if any signal splitters. This will reduce the amount of signal amplification needed. A signal splitter divides the signal reducing the signal strength. Each time it is divided more signal is lost. A 2 way signal splitter introduces 3.5 dB signal loss. A 3 and 4 way splitter 7 dB loss and 6 and 8 way splitters cause a 12 plus dB signal loss. This signal loss introduced by signal splitters and coax cable length can be counteracted with proper signal amplification.

A signal splitter is not a bad thing neither are long coax cable runs. Yes, both of these cause signal loss but this loss can be counteracted with the proper signal amplification. Signal amplification must take place within the system prior to the signal loss occurring. If you have a long cable run from the antenna to the TV a pre-amplifier is installed at the antenna before the signal loss of the longer cable occurs eliminating the effects of the long coax cable run. In this position the pre-amplifier will be ahead of the signal loss boosting the signal before the signal loss occurs counteracting the effects of the long cable run.

Distributing the signal to multiple TVs and getting better digital TV reception.

To supply signal to multiple television using the same antenna a signal splitter must be installed. The more times the signal is divided the weaker the signal becomes. Many times a pre-amplifier can be selected that provides the amplification needed to drive the signal through the coax cable and the signal splitter and then onto the TV's. Sometimes a distribution amplifier is all that is needed installed on the antenna side of the signal splitter. In some cases a combination of a pre-amplifier and distribution amplifier will yield the best results.

Balance the antenna signal distribution system for better digital TV reception.

When supplying multiple TV's don't daisy chain signal splitters. In other words, don't go from one signal splitter to the next and so on. One properly sized signal splitter installed with home run lines leading to each TV location is the most efficient method. If you must install multiple signal splitter keep it reasonably balanced. Don't have one cable line dividing the signal 6 times while another only divides it once. A good example is one 2 way signal splitter with each output of the splitter leading to a 3 way signal splitter. This configuration provides a balanced system for 6 TV locations.

I hope this page can help you get better digital TV reception and improve your digital signal. I invite you to visit our Digital TV Antenna Selector. The selector will choose the appropriate antenna and amplification requirements according to your location and system configuration.Next page


Understanding TV antenna range and reception.

Her,s a bit of reading

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And how about a topic on "How to install an HF transceiver antenna on a bathtub?"

I'd certainly subscribe to that, cos I haven't worked one out!

Well how about this?


HF grounding system for any yacht that is easy to install and cost effect. Price

Inc. VAT kiss-ssb-1.JPG KISS-SSB grounding system The KISS-SSB grounding system works on all frequencies from 2 MHz through to 30 MHz with an SWR of 1.2 or less and works just as good or better as the copper foil/bonding system. 

It comprises of a 119 cms lead that attaches to the "grounding lug" on your tuner (ATU) and then you just stretch out the remaining 3 metres long tube inside the hull of the boat. It is that easy to install:

  1. No drag when sailing.
  2. No need to drill holes in the hull under the waterline for a "grounding plate"
  3. No need to run the copper foil everywhere.
  4. No need to bond all the thru-hulls.
  5. Maintenance free.
  6. Can even be used when your boat is on the hard and not in the water.
  7. Helps save your expensive radio gear in the case of a lightning strike, as there is not a direct connection to water.
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For the higher HF bands the roof rail on a bathtub is very useful to tune against I have had good results on 40 metres and above using a moonraker SPX 300 multiband mobile whip clamped to the rail with an ordinary car roof rail mount. Might be a good idea not to transmit when anyone is likely to touch it though. Rail is clearly too short for 80 and 160

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  • 3 weeks later...

I've just come across this. 


I must admit that since the digital changeover even in the most historically awful reception areas we manage to get a good picture.  In fact last time we were on board at Brundall we still had a good picture when we took the aerial down.


Sometimes progress is good!



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