Calibration Vicious Cycle

[Alley_Cat_Jack]

I recently got a few old oscilloscopes. The one that is functioning needs some calibration. In order to calibrate it, I need a function generator. I don't have a function generator so I was considering building one. If i build one, then I need to calibrate it using a oscilloscope. If I purchase a used function generator, who is to say it will be calibrated? Is there something I am missing? Is there a way I can calibrate my equipment without having to pay big dollars to a calibration center?

[10101]

You can build / buy a frequency standard or more than one to calibrate the scope.
So just use the key words "frequency standard" on the forum and google
Any other doubts feel free to ask 

[10101]

https://www.eevblog.com/forum/projects/3-dollar-precision-frequency-standard/?all

[Alley_Cat_Jack]

Perfect! Thanks guys. You just saved me a lot of headaches. ^.^

[TheMG]

In a pinch, you can use a known voltage source (or any voltage source and an accurate multimeter) for amplitude scale calibration. For a rough timebase calibration, generate a tone from a computer sound card, 10kHz for instance. It should be accurate within less than 1Hz, more than good enough for getting an old analog scope in the ballpark anyways.

[edpalmer42]

If you really need to, you can always bootstrap your calibration climb with line frequency.  It's more than accurate enough for scope calibration.  Use a transformer to drop the voltage to a safe level, then trigger off that.  Extend the idea by using a function generator to generate a frequency that's N times greater than line.  Use your scope's second channel to display the function generator output and adjust the frequency until the trace stands still.  It's limited to low frequency and it can be a bit fiddley, but it'll get you started and it's free!

Ed