Audio Signal Generator: Cheap & Ready-Made

[wolram]

Dear sir.

I want to test my valve amplifier, to do so I need a signal generator, I do not want to buy a kit I want a cheap ready made one , can any of you guys tell me where to buy such a thing?

thanks.

 

[berkeman]

Can you just use the audio output from your laptop?

 

[berkeman]

Here's one free app for Windows: https://downloads.tomsguide.com/Tone-Generator,0301-61791.html

 

[anorlunda]

I use an app called "signal generator" on my android phone.

 

[wolram]

Thank you for your suggestions guys.