Frequency measurement with an oscilloscope, if it is done by measuring the time between zero crossings, is often subject to setup and operation errors. What is the scheme that your scope uses???

DSO's use the Trigger level edge if they have a native frequency indicator but you can use Cursors too or their Measurements offer a frequency counter also but all are subject to rock solid stable triggering first.

 

The dial calibration on some signal generators is often in error by at least 10%. So you really need to use an accurate frequency counter to verify the generator frequency. Checking the power mains frequency is also a quick check option.
You can also use a PLL IC and divider ICs to produce a stable multiple of the mains frequency. A CD4046 PLL and two CD4017 divide by ten ICs will give you a hundred times the mains frequency, either 5000 Hz or 6000Hz, which will be very stable.

 

How accurately you need to calibrate the scope will depend on what you are going to use it for. If it is just for electronic hobbies, you don't need to spend an awful lot on calibrators. You can use an Arduino to generate known frequencies with enough accuracy for most hobby purposes. it can also be used to make a frequency meter that will work up to about 5MHz.

 

You will need to find out how your scope measures frequency and how to adjust the calibration. BUT first you need to check your old function generator. After a year they may be off by a bit. AND, how long did you let it warm up before reading the frequency??

 

The word calibration implies a measurement against a standard ,
If you using a awg , then what's the accuracy of that ?
As some one says above , a good first step to check the scope, is to just pick up from the air, the mains frequency, 50 or 60 hz,
After that , things become more difficult.
An off the shelf tcxo oscilator can be 1ppm or better, and quiet cheap. Get, say 10 Mhz one from say Farnell, or digikey, see what the scope says .
Calibration of a scope , you need to find the maintenence manual for the scope , old analog / valve ones used to have a bunch of trim pots, but setup was a bit of an art, as changing one tended to affect the other settings as well,
Digital scopes, for timing use an internal oscilator , which tends to be either write or very wrong/ broken and needs replacing. Some scopes will have a 10 Mhz reference input, which the above oscilator you purchased coukd be of use.

 

In addition to the sources mentioned, there are often, in failed computer systems and other inoperative electronics, vet nice small oscillator modules, with the frequency marked on the case, needing only to be liberated from the PCB and fed five volts DC at a few milliamps, and you have, usually, a square wave of a few volts at the claimed frequency. AND, the similar items are also available from honest electronic distributors, mostly for between five and ten USdollars.

 

This has been handy for me in the past:

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I believe without knowing it has a crystal time base. The wave forms are very clean and crisp, if you magnify them you can see the digital steps.

 

This has been handy for me in the past:

View attachment 352873​

I believe without knowing it has a crystal time base. The wave forms are very clean and crisp, if you magnify them you can see the digital steps.

A signal generator is a very useful item to have even the tool kit,
I have two types , one as per @Wendy , is digital , the other is very very analog, with a light bulb amplitude stabiliser by the looks of it, but is low distortion sine wave

 

Here is a link to a similar DDs frequency generator similar to the one in post # 27
https://www.ebay.co.uk/itm/116669332127 This uses a 16 Mhz crystal as the reference frequency.
I have just done a test using one of these set to a 1Khz square wave. On my Siglent SDS1202X-E oscilloscope and it reads 999.942 hz. I do not consider either of these devices a frquency standard but they are both good enough for most purpses.
If I want better I use one of the broadcast frequency standards as a reference. You have not said what your requred accuaracy is.If you give us this information we wil be able to give better advice.
Les.

 

Hello,

If you want a very high precision source, here is a gps stabalized oscillator:
https://www.box73.de/product_info.php?products_id=5049

Technische Daten

Frequenzbereich 1 Hz…1,1 GHz
Ausgangspegel CMOS (3,3 V)
Ausgänge 1 (SMA)
Stabilität (GPS) besser 10-12
Stabilität (TCXO) besser 0,5 ppm
Stromversorgung 5 V (über USB-C)
Stromaufnahme 250 mA
Abmessungen 69 mm x 40 mm x 12 mm
Masse 40 g

Bertus

 

As suggested many times already, get a quartz crystal oscillator module.
Here is one that outputs square waves at 500 kHz on pin-1 and 8 MHz on pin-8.
It is powered with +5 VDC on pin-14 and GND on pin-7

 

THANKS, Mr. C! That is the sort of device I was describing in post #26. BUT I never saw one with dual outputs. But beware of the ones that rapidly vary the frequency in order to pass some EMI tests.

 

Do you have an audio DAC? You could use it as a signal generator.