my circuit does not working on the realworld

[SampathBandara]

Hi all

My circuit simulation working perfectly on the simulation. But in the real world, it would destroy the input signal and also output completely noise with distortion (input is 1 MHz sine wave, gain is about 40)

I soldering on the PCB and double check the soldering point

Sorry for my bad English

[johnsold]

The TI data sheet for the LMH6559 shows a capacitor between R8 and R11. Without that capacitor the DC bias may not be correct.

Lynn

[SampathBandara]

thank you for your kind reply

eventhough if it is not having a buffer. reselt is same as before.

I canot understand the situation

plase help me

[Inachosa]

Hi, could you explain to me a little bit more of what is it specifically that you are trying to do? Maybe we can work on finding a workaround for it.

[SampathBandara]

I am try to  make a ammplifire with buffer to drive coaxial cabale.

input is connected to the 50 ohm antena and output is connected to the DAQ card

Gain=50-40

I made anothe circuit it also work perfectly on the simulation but not in the real situation. (in put is almost destroted and out put is large noise)

[stressed_user]

have you got a screenshot of your layout?

Is the 50 Ohm resistor necessary after each opamp? I guess not...

[SampathBandara]

Thank you very much for your kind reply

so that, i am expected to compensate the impedance of the opamp, othe wise for low freqency lot of DC voltage create floting the signal.may be i am wrong