Frequency above 5 kHz not showing on Oscilloscope

[Shanza Baig]

Hello,

When I set the frequency of 5 kHz or below using the function generator, the oscilloscope is able to display the correct reading on screen. However, when I increase the frequency the value on screen reduces below 5 kHz and does not show the correct value.
Can you please guide me how can I see the correct value of frequency on oscilloscope. And also, if I have set 10 kHz then it's actually this value or the one the oscilloscope is showing is correct??

[themadhippy]

might be usefull to tell us the make and model of the oscilloscope as theirs a few to guess from.

[radiolistener]

Probably you're didn't adjusted horizontal time scale to fit with more high frequency. If you're using some Chinese toy instead oscilloscope it going to be more critical, because Chinese toys have very short sampling buffer and unable to see high frequency at slow horizontal scale.

[Aldo22]

Probably you're didn't adjusted horizontal time scale to fit with more high frequency. If you're using some Chinese toy instead oscilloscope it going to be more critical, because Chinese toys have very short sampling buffer and unable to see high frequency at slow horizontal scale.

Even the cheapest china scopes have an auto-button that makes the correct settings for you.

But without more information from the OP we can't narrow down the problem.

[richnormand]

First, hook up you signal generator to an audio line amp input (below half a volt max)  and sweep it from 5kHz to 20 kHz and listen to the sound.
If the output drops rapidly before 10kHz the generator might be defective. After that, as the frequency goes up to 10 kHz, its your ears, depending on your age.

Second, your provided no info on the oscilloscope. Even a real 1950 CRT scope will do better than that.
If it is a legit scope, it might be defective or have a blown input. Check 50 ohm vs 1 meg impedance on the scope that might load up a cheap generator?

Three, how is it connected (or badly connected) to the signal generator?

[807]

A photo of the complete setup would be helpful too, showing the generator frequency setting & the scope display.

[CaptDon]

Sweep rate set wrong and signal is aliased.