Signal Generator

Do you have a circuit diagram?

Do you understand the functionality of the circuit your trying to faultfind?

Do you know much about electronics?

are you trigguring the cro on a known timebase?

No I have not any circuit diagram.

No I am not understanding the functionality of the circuit.

No much experience in electronics but very interested to gain some practical experience in electronics.

No trigguring.

Do you mean you can't get the scope to trigger or you aren't even trying?

Does the generator have a "trigger out" connector or something like that?

In either case, the scope display won't be very helpful if it's not triggered.

Said nicely - you are diving way to far into the deep end. Start on something simple to learn and give the complex repair problem to someone with experience.

I am working(troubleshooting) on Lab Equipments,and there are some problems in fault finding,( I am a diploma holder and still studying,I required some practical hints about testing components using in labs instruments and troubleshooting ).

Thats why I questions about RF generators.

It seems you're fishing on unchartered waters.

What you're doing? Are using a scope linked directly to the rf. generator? What you're describing sounds like you may have just an earth problem between the test equipment and the circuit (or the rf. gen.) you're testing.

Sorry, cannot help because you should provide more info to let us know what you're doing.

I mean that when I give a signal from RF generator to Oscilloscope,and the oscilloscope shows a combination of signal waves.

Is there any earth problem with RF generator ?

I am cecking direct RF signal on Oscilloscope as I connect other RF generator to Oscilloscope that shows proper signal frequency which provides.

Perhaps the signal generator has modulation turned on.

In that case forget the earth problem because both would be earthed and ideally they should have earth link to one another.

It seems more you don't know how to operate that rf. generator nd you'd need to get the manual for it or simply keep on fiddling with it until you get it right.

Try not to drive with it (use it) until you know what you're doing, they're usually expensive and should be calibrated annually!

You also need perseverance!

OK, here is some background on the problem your dealing with. A signal generator typically starts with a sine wave generator, a high frequency clock circuit. The general scheme of the thing is; low voltage DC power, to a clocking circuit, to a low voltage signal conditioning circuit that modulates the clock circuit to the desired final form, to a higher voltage DC switching circuit which produces the final output of the device.

If only some of the pulses are to be output which is typical then the low voltage square wave train is sent through a chip set that clips pulses and or sums them together to give the required output wave train.

This modulated wave train then controls a amplifier circuit that steps up the voltage and amperage to the final stage - the output.

Since your initial comment seems to indicate #1 that there is a fault with the device and #2 that it does select for wave form, ie. square, vs. sine, etc. Then my guess is that the fault lies in the circuit that is designed to clip and or sum the wave form.

Further guessing passed on your comments says the problem lies with the chip that clips the low voltage signal based on input from the frequency selector control knob, button, display, program.

So, you MAY be looking for a fault near the last stage of the low voltage circuits output to the step up high voltage output. Or, a fault in the connection between the frequency control system / circuit and the late stage signal processor I just mentioned, or something else.

There will be a diode to protect the low voltage chip sets from the high voltage amplifier circuit. If this is blown the signal clipping chip referred to above will blow and when replaced will blow again.

Failure to connect the device to a load of proper resistance and impedance will tend to cause this fault and that sort of operator error is pretty common.

Search online for the manual. There will be a seller or reseller of the manual. Look on E-bay if nothing else. You will need the manual to fix the device and if it is not with the device it will soon be broken again.

Best wishes,

Mr. Gee

(Seek local qualified assistance and buy them a small nice gift when and if they do agree to help you.)

tfkhan said that it IS an RF Signal Generator. The sine, square, rectangular wave IS most likely internal modulation. With modulation on, one would see a combined waveform. If you desire to observe the modulation, then trigger from the modulation output. The generator should have one.

Ok, if your in a lab....

Do you have a 2nd sig-gen?

If yes, and its a known working one, use that as your "Golden sample" and trace the circuit for differances between the good and the "problem" unit.

scope not synced to gen freq? Multiples of fundemental displayed.

take a photo is best