Waveform amplitude too small

I am using Audacity 2.0.0 on a MacBook Pro, 10.7.5. Recording form an Audio-Technica USB turntable.
I am able to record, but the wave-form is very small, never even approaching 0.5 on the scale. I would like more amplitude for better sound quality when I export. But I find no way to increase the input volume as any sliders I find are greyed out. And my Mac Preferences under Sound/Input/USB Audio CODEC says : " The selected device has no input controls." Help. Tom Bloom

Check the manual for the turntable and/or give it a close visual inspection. Some USB turntables have a volume control - it is sometimes “hidden” on the bottom of the device. Not all turntables have a volume control - with some you are stuck with the manufacturers preset level. If all else fails, use the Amplify effect in Audacity after you have recorded.
Note that with digital recording you do not need to “maximise” the input level. A peak level of about half the track height is ideal, so you may not be as far off as it may appear.

Thank you thank you!! (Not only am I not very good with digital equipment, I’m pretty awful at Forum navigation. Your reply is concise and very helpful! Thank you. I’ll follow thru, and particularly, the advice about not worrying about amplitude is very reassuring. Thanks again. Tom

Just to add to what Steve says here: this level is good for capture and for all of your editing. As the last stage in your prpcessing just prior to exporting your production files you can the up the volume with Normalize or Amplify - I wouldn’t take it up to the maximum 0 dB as some players don’t like that - stick at about -1 dB (personally I Amplify to a a max level of -3 dB and I find that plenty loud enough).