Today, just for the fun of it, I searched amazon.com for HD radios.

I found 6 HD car radios, including units by JVC, Sanyo, Dual and Jensen.

There were also 5 HD tuners from Sony, Directed Electronics, JVC and others.

Tabletop radios? Not quite as good a selection there as I counted just 3 – from Sony, Directed Electronics and Polk Audio.

If you didn’t know the difference, you’d think there weren’t many tabletop HD units available. But what’s missing on amazon.com are radios from RadioShack (Accurian), Radiosophy (HD100.1), Boston Acoustics, Cambridge SoundWorks, iLuv, Insignia (BestBuy’s house brand), Jensen, Marantz, Sangean, Visteon and probably a couple of others I might have missed.

In the final category, receivers, amazon.com lists just one from Onkyo. But again, there are a number of others available – most on the high end – from manufacturers such as ADA, Yamaha, Niles Audio, Integra, Denon and DaySequerra, plus the more reasonably priced Sangean receivers.

I found it interesting that amazom.com didn’t offer more HD radios but have no idea why this is this the case. Does it have to do with radio manufacturers and what kind of a deal they’ll give amazon.com or is there some other, darker reason?