# Recent content by countmybones

1. ### Waveguide isolator and coupler manufacturers

Hi, we are looking to purchase WR12 waveguide isolator and couplers. Being new to waveguides, can anyone recommend some reputable companies that manufactures these components?
2. ### [SOLVED] Single ended to differential signal conversion

Thanks! That's it, the output with the 'o' symbol was swapped.
3. ### [SOLVED] Single ended to differential signal conversion

Hi all, May I know why the following circuit output common mode voltage is not 0.9 V?
4. ### Anybody know about Scilab 5.0.3 installation?

Well, the product page for Scilab 5.0.3 does not list Windows 7 as one of the supported OSes. Maybe you can try running it in compatibility mode, or get the latest version?
5. ### Modified distribution from normal distribution

Hi all, what do you call the distribution generated from these steps: 1. Generate a normal distribution with mean = 0 and standard deviation = 1. 2. Make all the negative data from the distribution positive, i.e. magnitude or absolute the number. 3. Plot the new distribution that now contains...

7. ### Output impedance of opamp

Hi FvM, is the attached figure the correct way to do it? The op-amp inputs are shorted to ground because if we want to evaluate the effects of the current source, all other sources must be made 0, from superposition theorem, right? Then plotting the output voltage/current is the output impedance...
8. ### Output impedance of opamp

Hi all, what we have learnt is that the output impedance of an opamp is very small. I cannot seem the find this information in the datasheet of the opamp I am looking at. May I know how can I measure the output impedance of an opamp using only spice?
9. ### [SOLVED] Op-amp voltage follower not following input

Ok, I managed to import the OPA683 spice into LTSpice and it simulates fine at +/- 3.3 V.
10. ### [SOLVED] Op-amp voltage follower not following input

The datasheet says power supplies from +/- 2.5 V to +/- 6 V, so I think +/- 3.3 V should work. These are simulated results using TINA-TI, available free from TI.com. I reran the simulation placing Rf and also changing V1 to 1 V. The DC sweep for Rf from 0 Ohm to 2k Ohm using +/- 3.3 V supplies...
11. ### [SOLVED] Op-amp voltage follower not following input

Hi, I have a simple op-amp voltage follower using OPA683. When the op-amp is powered by +3.3 V and -3.3 V supplies, the ouput voltage maxed out at ~200 mV when I change the input from 0 V to 1 V. But when I change the power supply to +5 V and -5 V, the output follows the input. Any idea why...
12. ### Why we use 50MHz as a reference?

Thanks for the replies, but I think the question is why 50MHz instead of why 50 Ohms.
13. ### Why we use 50MHz as a reference?

Hi, Why in measuring RF power, a commonly used reference is 50MHz? Why not 100MHz or 60MHz or 55MHz? Thanks.
14. ### Difference between average and CW power

Hi all, When measuring RF power using a power meter and power sensor, what is the difference between average power and CW power? For a sine wave type of signal, is the average power and CW power the same thing? What about for a pulsed signal like GSM, which I suppose there will be no CW power...
15. ### Capacitors operating frequency

Hi all, how do I know what is the maximum frequency that a particular capacitor can handle? Some datasheets I came across don't specify this thing. I need to find capacitors that will be able to work up to 5GHz. Thanks.