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This is a difficult one to answer, mostly because RF and EMI are so incredibly non-intuitive. One might say that if someone claims to understand EMI then they most certainly do not understand EMI. I do not claim to completely understand EMI. I know a lot about it, but I have some holes in my knowledge. Consider that when reading my answer. My main ...

You don't have to spend a million dollars do get a decent VNA. Since you have the skills to build circuits, you can build one yourself for about $400 USD. I've been building up a N2PK VNA over the past several months. You don't need any special tools, just a steady hand, and a good soldering station. There's an active Yahoo Group, in the files section there ...

Yes, it certainly is possible. What you do is have some decoupling caps between the two planes, near any place that the LVDS signals cross from one side to another. The idea here is to give a place for the AC signal return path to cross over from one plane to another. Of course, being LVDS, most of the AC signal return current is on the other side of ...

The LVDS are differentially terminated (across phases) so there should be no net flow of current - it is balanced. The twisted pairs give you quasi TEM mode propagation so the concern of the shield here is purely electric field. terminate at one end as you have drawn to avoid introducing current loops. Since you have implemented a differential CAN system ...

Here's the cheapest I can come up with. First, you need an rf synthesizer. If you don't have that, get your digital signal to output a pure square wave (either use the clock signal or send 1010... from your data line), and then use a lowpass or bandpass filter to transform that into a pure-ish sine wave. Between the source and your circuit under test, ...

I don't think you would get significant reflections. If the load impedance is matched to the transmission line, there would be no reflections on that transmission line. In reality there's a tiny transmission line between the driver load and the long transmission line, so there's an opportunity for reflections there. Think of it this way: "looking into" the ...

I've had problems with a similar arrangement where the R.H. 3V3 regulator circuit needed better decoupling to prevent switch-mode currents taking a partial route through data screens that were grounded at both ends. I'm not saying don't ground at both ends, just be careful about the 3V3 regulator if it is a switcher. The problem manifested itself as ...

Background: One of the more common things in the last decade is laptop (and some desktop) producers using usb as a catch all bus, instead of dedicated hardware for peripherals. Instead of designing and including sometimes space intensive hardware for many parts, they just design with bridges with a few usb ports in mind, and hubs to expand them. Everything ...

How exactly does this work? Particularly line arbitration From p. 10 of the datasheet, "DQS is a strobe transmitted by the DDR2 SDRAM during READs and by the memory controller during WRITEs" Timing diagrams on p. 78, p. 82, and elsewhere show more details of how the signals are used. Basically the DQS lines are kept in high-Z until the type of ...

Now fixed. The LMH7322 has ECL outputs. It is capable of providing LVDS levels, but this is not true LVDS. The outputs therefore need termination to ground (or another voltage below VCCO-2V). I replaced the single 100 ohm termination resistor between the outputs with two 50 ohms, each to ground, and now the output is as expected. There are therefore a ...

In my opinion, the most obvious thing to do is to build an oscillator (or a multivibrator, to have square waves) with variable frequency and look at the signal at the other end of the cable if the degradation is acceptable. But first you should define some dimensions: 100 Mb/s it's the overall bandwidth or only for the payload? You should first convert it ...