There are three methods to get the over the air (OTA) high definition digital format signals.
The first option and cheapest is to buy a DTV converter box and continue to use your old TV set. The signal will be clearer and have less noise and ghosting than it once did with the old analog signal. The signal detail and sharpness won't be anywhere close to what a new HDTV can do for the image but if you can't afford to buy a new tv than this may be a good way to go. You will still be receiving standard definition TV. The low cost DTV converters do not output a high def signal. If you already have a TV capable of High Definition you can buy a more expensive HDTV converter like the Samsung DTBH260F HDTV Terrestrial Receiver. The Samsung receiver can receive and output high definition signals to your HDTV monitor.
If all this seem overwhelming, you could always go with satellite. You can get some great area specific satellite deals like the Direct TV Phoenix specials. You can often save quite a bit of money following this route as opposed to going straight through the provider.
DTV Converter Box Pros:
The second option is to buy a VCR, DVD player/recorder or Hard Drive Video Recorder like the Philips DVDR3576H/37 DVR that has a built in ATSC tuner. Just like your old TV, your old VCR is not going to work either. The disadvantages are the same as the converter box method, but at least you can record the signal. I believe none of these type recorders actually record in HD. They downscale the image to standard definition and record that. Even so, the DVD and hard disk recorders still produce a much superior image than using VCR tapes.
Addon Recorder/Player Pros:
Buy a new HDTV Pros:
Everything is not all great with digital TV. There are a few issues I have experienced. The most annoying is when I use the microwave oven, it interferes with the digital signal. With analog signals, I can see some interference lines, but it is still watchable. With the digital signal, it chops, cuts etc. to the point where it's unwatchable. I have also seen degradation of the signal in severe weather as well. In the end, I think the benefits outweigh the issues. Would I go back to regular old analog? NO WAY!
So which HDTV should you get? That's not an easy question. There are many different technologies out there and each has their strength and weaknesses. You will have to decide what is suitable for your budget and the intended placement.
CRT - Long live the Cathode Ray Tube
Pros: Well tested technology. Good motion and natural looking images. Less expensive than same size flat pannel TVs. Can screen burn but you have to really abuse it.
Cons: Deep, bulky and heavy. Not many to choose from.
Pros: Excellent color and clarity. Less expensive than same size flat pannel TVs. No screen burn.
Cons: Unequal brightness on some models. Spinning color wheel - In some units you can hear the motor spinning. Possible rainbow effect. The better units have 3 light output devices instead of one. This removes the need for the spinning color wheel and possibility of the rainbow effect. Needs more space than flat panel. Expensive bulb that has to be replaced (unless you get one with an LED light source). Off center viewing not as bright as flat panels.
Pros: Good color and clarity. Less expensive than same size flat pannel TVs. No screen burn.
Cons: Expensive bulb that has to be replaced. LCD has possible screen door effect, less noticable on newer models. Needs more space than flat panel. Off center viewing not as bright as flat panels.
Projector (LCD or DLP)
Pros: BIG theatre style picture. No screen burn.
Cons: Expensive bulb that has to be replaced periodically - Shorter bulb life than even the projection TVs. Poor black and contrast levels except the most expensive models. DLP subject to rainbow effect. LCD subject to screen door effect. Best in dark rooms. Noisy fans. Difficult placement and setup.
Original CCFL LCD Flat Panel
Pros: Thin wall mount placement. Good brightness, color and contrast. No screen burn.
Cons: Some models have white washout with some scenes. Scene movement not as natural as the other technologies. Get the lowest millisecond response time you can find. 120hz refresh helps here as well. The non-LED backlight models are power hungry, but not as bad as plasma.
LED LCD Flat Panel
Pros: Thin wall mount placement. Good brightness, color and contrast. No screen burn. The new LED TV backlit models use less power, are even thinner still, provide an even better contrast ratio and a wider color gamut.
Cons: Cost aside, are there any cons? I have to admit, these new LED TV's are hard to beat.
Plasma Flat Panel
Pros: Thin wall mount placement. In my opinion, Plasma TV's have the best combination of brightness, color, contrast and scene motion. The images look natural as they should.
Cons: Power hog. Plasma TV's use 300 watts or more. You can feel substantial heat being generated. Possible screen burn with still images although less likely on newer models. Reliability is questionable with the required high voltage power supplies.
OLED Flat Panel (Organic Light Emitting Diode)
Pros: Thin wall mount placement. Low power consumption. Super fast response time. Even better than Plasma and CRT.
Cons: Available only up to 40" so far. Color balance issues, screen burn and questionable life span.
I hope this has provided you with some useful information. Good luck in the digital TV age!