Can most op amps get up to 50,000 hertz?

[Qaiphyx]

^^^

asdf

 

[Hero999]

That's a meaningless question.

What do you mean by most op-amps? You haven't given any examples.

It depends on the peak output voltage and the gain of the design.

The :mu:A741 has a full power bandwidth of only 8kHz and its gain goes down to unity at 700kHz (worst case). For example you can use it at 50kHz with a gain of say 3 with an output voltage of just 500mVp-p but it you want 10Vp-p then forget it.

 

[Qaiphyx]

That's a meaningless question.

What do you mean by most op-amps? You haven't given any examples.

It depends on the peak output voltage and the gain of the design.

The µA741 has a full power bandwidth of only 8kHz and its gain goes down to unity at 700kHz (worst case). For example you can use it at 50kHz with a gain of say 3 with an output voltage of just 500mVp-p but it you want 10Vp-p then forget it.

Hmm, I dont get it. Radio stations need massive amounts of current to transmit their signals and they need to create sinusidal waves to do it with, how do they create so much current if op amps cant handle so much voltage??

 

[crutschow]

Hmm, I dont get it. Radio stations need massive amounts of current to transmit their signals and they need to create sinusidal waves to do it with, how do they create so much current if op amps cant handle so much voltage??

Op amps are generally used at low voltage and power levels. Radio station transmitters use massive high power amplifiers with large discrete devices These have little similarity to an op amp other than that they are both amplifiers. There are generally multiple stages of amplifers between the low level signals and the transmitter output.

Sounds like you need to look up some basic tutorials on ampliifers and electronics.

 

[Qaiphyx]

Op amps are generally used at low voltage and power levels. Radio station transmitters use massive high power amplifiers with large discrete devices These have little similarity to an op amp other than that they are both amplifiers. There are generally multiple stages of amplifers between the low level signals and the transmitter output.

Sounds like you need to look up some basic tutorials on ampliifers and electronics.

So they create the sinusidal wave, amplify it, crank the voltage and then send it through the transmitter?

 

[Qaiphyx]

Op amps are generally used at low voltage and power levels. Radio station transmitters use massive high power amplifiers with large discrete devices These have little similarity to an op amp other than that they are both amplifiers. There are generally multiple stages of amplifers between the low level signals and the transmitter output.

Sounds like you need to look up some basic tutorials on ampliifers and electronics.

So they create the sinusidal wave, amplify it, crank the voltage and then send it through the transmitter?

Do you have any links to some good tutorials on this?

 

[crutschow]

The audio is actually amplified and then used to modulate (either AM or FM) the high power transmitter amplifier which is oscillating at the radio carrier frequency.

I don't have any particularly tutorial sites in mind. You might try https://en.wikipedia.org/wiki/Main_Page and search for electronics or Google "electronics tutorials" as a start.

 

[audioguru]

Audio is from 20Hz to 20kHz. It can modulate a carrier frequency that is up to many gHz.
One gHz is 1,000,000,000Hz.

 

[Qaiphyx]

What would be the best suited op amp for hitting this frequency?

 

[Hero999]

As you haven't stated your gain, load and power requirements we can't suggest anything.

 

[Speakerguy]

Let's go back to square one:

What are you trying to build?

 

[audioguru]

He is trying to make a radio station with a single opamp.

 

[Hero999]

Yes it's hard not to laugh at nubes but we shouldn't pick on them.

 

[Speakerguy]

He is trying to make a radio station with a single opamp.

That sounds like a challenge... can I use any opamp?

 

[audioguru]

Try making an AM broadcast band radio transmitter with a lousy old 741 opamp.

 

[Speakerguy]

Well, a uA741 will swing about 0.2Vpk at 500KHz.... how far does it have to transmit

 

[Qaiphyx]

He is trying to make a radio station with a single opamp.

lol. Actually im mainly just trying to learn a thing or two with electronics. Theres a lot of things I want to do/build, and Ive already learned quite a bit, but I may not have all the specifics and details. Ive already made a 555 pulser circuit and a phase shift oscillator, which actually didnt work yet cause Ive had trouble with gain, for as much as I know and the amount of time that I have spent on it I know quite a bit. Just bear with me, I am new, but I learn fast Oh and you cant listen to my radio station when its done! lol.

Well, a uA741 will swing about 0.2Vpk at 500KHz.... how far does it have to transmit

12 volts is the battery type ill be using, im gonna set up a dual input for it. It doesnt have to transmit far, but I will need to amplify the circuit to 30 - 100 watts, then crank the voltage up with a transformer.

oh and as for gain, im still not quite sure, I havent really grasped the concept of gain :/ I just know its fickle and has to be just right for the opamp to oscillate.

 

[audioguru]

Do you have a licence from the government to operate a radio station? On thier chosen frequency?
Has the government passed your promised type of music/talk?
Is the radio transmitter certified so that it does not cause interference?

 

[Qaiphyx]

Do you have a licence from the government to operate a radio station? On thier chosen frequency?
Has the government passed your promised type of music/talk?
Is the radio transmitter certified so that it does not cause interference?

Lol relax man I was just joking. Im not using it to transmit radio frequencies.

 

[Hero999]

Well you said you wanted to transmit 300W.

What do you want to do then?

There are many different types of oscillators.
https://en.wikipedia.org/wiki/Oscillator#Electrical