FM/AM Tuner under around $500


I am looking to purchse a tuner but I do not really know the terminology involved or what the numbers associated with those words actually mean. If anybody can help on the following list it would be appreciated.

Selectivity:

Harmonic Distortion:

Separation:

S/N Ratio:

Capture Ratio:

Also if you have any product ideas for me to look and that as well ($500 range)
bianchi27
As for what all the words mean, try these links:

http://www.fanfare.com/fm-specs.html

or

http://www.theabsolutesound.com/newsletter/5_14_2003/142_howto_tuner.html

I'm sure there are others that might be better, but they should provide what you need even if lengthy.
Actually, the first link by Lngbruno if the best, and was the one I was originally thinking of but couldn't remember. Should have read the post more carefully.
The first thing you need to decide is whether you want a modern digital tuner that has preset stations and a remote control, or, whether you want a vintage manual dial tuner.

Next you need to decide whether sound quality, or, the ability to tune in hard to get stations is more important. Easier to get a good sounding tuner than one with great tuning ability.

Before you decide, any recommendation is not worth as much. There are great tuners in each catagory, and some that do pretty well at everything (with compromises). The Yahoo Group and the Tuner Information Center (Fmtunerinfo.com) are the best places to go. Both sites are moderated by the same small group of people.

I (and some other Agon members) have contributed comments to the Tuner Information Center, but they use real first names instead of made up screen names; so you won't find "Sugarbrie" there.
thanks for your input guys, very informative. I know I want to go digital and put tuning in stations above sound quality (although both are important). My main purpose is too get as many public radio stations as possible. There is great station about 45 mins to 1 hr from me but they have a weak signal.
Especially for the weak signal, getting a good directional FM antenna well above your roof--especially with a rotor, correctly aimed--this will make the most difference. Within the tuner, it's sensitivity that makes the most difference for far away stations. (lower number is better).

Best bang for the tuner buck, especially in distance reception would be a vintage tuner that has been modified, resulting in excellent sensitivity. Here is just one place to look:

http://www.antennaperformance.com/

....sell modded vintage tuners, giving you excellent reception for your $. They also sell high performance FM antennas.

I'm not associated. There are other people/companies, too. But my point is that restored & modified vintage would work best with your budget.