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
For a real killer tuner. Pick up a vintage Pioneer TX-9800 am/fm analog tuner. This tuner is amazing in every way.
TX-9800 weighs about 30 lbs in a nice cabinet. They are a steal if you can find one under $275.

It's close in a lot of ways to being as good as my other tuner the Marantz 10B (tubes gives it the warmth edge)
I'm not a tuner expert but you may want to consider a Magnum Dynalab FT-101A. I've read a number of comments on them that they are not that well made but I have one and have been perfectly satisfied with it. Then again, I haven't spent a lot of time searching out alternatives.

You can generally find used FT-101A's here on Agon for under $500.
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.