Is it possible to use the calculator on Windows 7?

Waiting for your helpful response.

USB Monitoring

Just wanted to say thanks for sharing your calculator, it certainly removes some of the manual equations.
I'll still need to breadboard my device before implementing to see if anything needs playing with (i may need a comparitor/opamp to boost or rectify the signal, unsure yet).

My device is a miniature VU for a headphone amplifier, i'm slightly modifying a circuit by NwAvGuy (o2 amplifier) but this VU part will fit somewhere and will power only on DC jack input to save the battery power when mobile, i'm making it mostly from SMD except some of the chips as they're quite costly in sop/ssop/tsop but have worked my design on Eagle and the mirrored circuit looks quite nice.

when i've worked out how to etch copper tape on glass and solderd the parts (i've tested the copper tape to glass and soldering with success) i'll post a few pictures somewhere with a step by step guide, i'm not planning to built too many..... its just something i fancy doing for myself, i'm no techy...... merely a cashier for William Hill bookies but i enjoy a challenge.

anyway.... sorry for rattling on..... thanks again for sharing.
Best regards, Wayne.