For those of you who still have old computers running Windows XP (32-bit) or any other Windows 32-bit OS.PROGRAM WILL NOT RUN UNDER VISTA OR WINDOWS 8 or any other 64-bit OS.
Tube CAD helps you design tube audio gear by doing the hard math for you. This program covers 13 types of tube circuits, each one divided into four variations: 52 circuits in all. The metaphor used is that of a notebook with 13 pages--one for each circuit type. Clicking on the tabs at the bottom of the program brings up that circuit page. Tube CAD calculates the noteworthy results, such as gain, phase, output impedance, low frequency cutoff, PSRR, bias voltage, plate and load resistor heat dissipation, and needed power supply wattage capability.