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Connect Converter box for both Analog and Digital TV

TV Solutions:In the Digital Age

Using your old analog TV and two digital converter boxes, here is a way to watch one TV show while recording another: How to record one TV program while watching another. Use one digital to analog converter box to watch one TV program and use a second converter box to record a second TV program to a VCR or DVD recorder.


Do you have a television set in your home that works with the help of ?rabbit ears? or a rooftop antenna?

Television broadcasting is moving from an old standard ? known as ?analog? ? to a new standard, called ?digital.? After June, 2009, all television broadcasts will be digital. After June, 2009, all analog televisions getting programming ?over the air? through an antenna will need to be plugged into a television converter to receive digital TV broadcasts.


A ?digital-to-analog? converter is a device that plugs into your television set. Plugging a converter into your existing television will allow you to continue to get your programs after February 17, 2009. The converter option is not for everyone. Most people have television sets connected to cable, satellite, or other pay television service. Converters will NOT be needed for these TV sets. If you have a television with a digital tuner, then you will not need a converter. If you haven?t purchased a television in the last five years, it probably does not include a digital tuner. An older set not connected to cable or satellite service is a good candidate for a converter.

On February 17, 2009, (pushed back to June 12, 2009) federal law requires that all full-power television broadcast stations stop broadcasting in analog format and broadcast only in digital format. Here?s what these requirements will mean for you and your television viewing.

Why Are Broadcast TV Stations Switching to All-Digital?

Congress mandated the conversion to all-digital television broadcasting, also known as the digital television (DTV) transition, because all-digital broadcasting will free up frequencies for public safety communications (such as police, fire, and emergency rescue). Also, digital is a more efficient transmission technology that allows broadcast stations to offer improved picture and sound quality, as well as offer more programming options for consumers through multiple broadcast streams (multicasting). In addition, some of the freed up frequencies will be used for advanced commercial wireless services for consumers.

How Do I Receive Digital Broadcasts If I Don?t Subscribe To Cable Or Satellite?

If you receive only free over-the-air television programming, the type of TV you own, either a digital TV or an analog TV, is very important. Consumers who receive only free over-the-air television may view digital programming through a TV set with a built-in digital tuner or a digital-ready monitor with a separate digital tuner set-top box. The only additional equipment required to view over-the-air digital programming with a DTV is a regular antenna, either on your roof or a smaller version on your TV such as ?rabbit ears.? If you have an analog television, you will have to purchase a digital-to-analog set-top converter box to attach to your TV set to be able to view over-the-air digital programming.

Analog-only TVs should continue to work as before with cable and satellite TV services, gaming consoles, VCRs, DVD players, and similar products. Over-the-air digital set-top boxes can be purchased at retail stores. Because most broadcast stations in all U.S. television markets are already broadcasting in digital, consumers are further advised to contact their local broadcast stations to determine the channel numbers on which the stations are broadcasting digital programming. Consumers should then ensure that their televisions are set up to receive over-the-air programming, and then tune to the over-the-air digital channels to see if they can receive the digital broadcast programming.

What About My Analog TV? Will It Still Work?

After February 17, 2009, you will be able to receive and view over-the-air digital programming with an analog TV only by purchasing a digital-to-analog set-top converter box. Between January 1, 2008, and March 31, 2009, all U.S. households will be able to request up to two coupons, worth $40 each, to be used toward the future purchase of eligible digital-to-analog converter boxes.

If I Already Have an Antenna, Do I Need a New One to View the Digital Signals?

A special antenna generally is NOT needed to receive digital signals. A good standard antenna which can receive UHF TV signals is all you need. You may have antenna issues, however, if your current antenna does not receive UHF signals (channels 14 and above) well, because most DTV stations are on UHF channels. In such a case, you may need a new antenna or to add a UHF section to your existing antenna system. Digital TV broadcasts use the same band of broadcast frequencies as before (VHF/UHF) so you may already have a good antenna (indoor or outdoor) that will pick up digital TV just fine. Some retailers market TV antennas as "Digital" or "HDTV" antennas. This is misleading as they are the same antennas as before.

Analog RF Signal Pass-Through:

This is extremely helpful for people who will still be receiving analog broadcasts from low-power and translator TV broadcast stations that do not have to transition to all digital TV. This feature allows a converter box to pass through analog signals without interruption, to your existing analog TV. This allows switching from a digital channel received by the converter box to an analog channel (passing through the box) to be viewed on your TV. Not all CECB converter boxes have this analog pass thru feature.

Those converter boxes that do have this analog pass-thru feature function as follows:
You can view analog TV stations simply by powering off the converter box and using your analog TV to tune channels. Keep all cable connections the same, the antenna picks up the analog TV station and passes the signal thru the converter box (and your VCR if connected by RF coaxial cable) and on to your TV just like the converter box was not there.

Many people will not need analog pass-thru, but for those who do, you can still get the same result if you use a signal splitter and a "A/B switch" connected to your TV. A digital to analog converter box without this pass thru feature will work just fine if you hookup the splitter and A/B switch as shown below. Then you can switch between analog TV programs and digital TV programs.


o Signal splitter.
o A/B switch.
o Digital to analog TV converter box.
o One set of Audio/Video RCA cables.
o Four RF coaxial cables (RG-59 or RG-6).

With this setup, the antenna picks up VHF and UHF TV signals and passes them to the splitter. The splitter provides a signal to the converter box which processes and outputs to the A/B switch, which when in the "B" position, passes the signal to the TV. When in the "A" position, the switch passes the analog TV signal to the TV. When watching analog TV signals, you will tune the channels on the TV set. When watching digital TV, you will tune the channels on the converter box and select channel 3 (or 4) on the TV set.

Hookup for analog TV without A/V inputs, only a single RF jack. Converter box does not have passthru feature.

If you have a TV with Audio/Video inputs, then you can use a modified hookup which does not involve the splitter, only the A/B switch. With the switch in the "B" position, you watch analog TV as before and with the switch in the "A" posiiton, you watch digital TV. Select the proper input on the TV with the TV remote. Tune channels on the converter box when watching digital TV stations.

Hookup for analog TV with Audio/Video RCA input jacks.

A/B Switch

An A/B switch is a mechanical selector device that allows you to choose which signal source your TV uses at any given time. You may also find an A/B switch useful for connecting a home video-game system, or for advanced TV viewing options, such as watching one channel while recording another. A/B switches are available in a small manual type where you slide the switch to one side or the other, or a remote control type where you do not have to get up from your easy chair to flip over to the other side.

For those converter boxes that do not support "RF Pass Thru".

Of course, even with RF Pass Thru, you'll have to switch between changing digital channels on the Converter box and analog (NTSC) channels on your old TV.

Google search for A/B switch

RF Splitter

Google search for RF splitter

RF Splitters are rated in two ways: The frequency range they are designed to handle, and the insertion loss incurred when a signal passes from the input to any of the outputs. A frequency range of 55 Mhz to 900 Mhz covers the VHF, UHF, FM, and CATV bands. The insertion loss is measured in dB. The lower the number, the better. The loss in a good splitter is around 4.0 dB per split. An average splitter has around 4.5 dB loss per split.

Home Depot, Wal-Mart, Radio Shack all sell these splitters for home use.

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