Electronics tutorial - Resistive (lossy) impedance matching

[@Masoudmpo]

Thanks for these contents. I really like your video format. Clearly explaining the problem followed by simulation and test setup. You are now my go to channel for RF and electronics next to w2aew.

[@Fr1392]

You made important concepts much clearer, where every other video or website i saw did not, despite loads of text. Thank you very much!

[@FesZElectronics]

I'm happy you enjoyed it! In the mean time (since this is an older video) I expanded this video series with a few more episodes concerning lossless matching - maybe those will also be of interest to you!

[@juanchirino7135]

Excellent approach to the topic, i study this at university in the subject " electric-network theory 2", but the approach was the other way around, first we study dual port networks L type, and the an application of this was impedance matching. Those experiment helped me to understand better the topic cos to the fact that this year laboratories was closed for the COVID-19 pandemic. Saludos desde Argentina!!

[@FesZElectronics]

I'm happy to be able to help in these times... Keep safe!

[@Electronzap]

Good video, impedance matching makes a lot more sense now.

[@EmmanuelR613]

Very nice video. You're dealing with a problem I find rather complex. I didn't realize until watching your video that LTSpice could simulate propagation in wires. I would just do one remark. When you add a resistor in parallel to an other one to match the cable impedance, it is worth mentionning that it works only because the two resistors are close enough from each other compared to the wavelength. Otherwise, we're faced to an other transmission line between the two resistors. That's the only point that was not clear to me.

[@FesZElectronics]

You are right, the distance between components is critical in deciding whether the "trace" is just a 0R short circuit, or a transmission line. In general if the propagation delay trough the trace is comparable to the signal wavelength then it needs to be treated as a transmission line.

[@__--JY-Moe--__]

I have 2 be aware of impedance matching, with my base station networks! a very important complication, in RF. a very helpful full lecture video!! best regards!

[@gillywild]

Excellent stuff :) I learned a lot. Thank you :)

[@MIsam-fv9kb]

very informative video

[@TheSriram1990]

Excellent video.One small suggestion_> you can share the Ltspice simulation file with every video

[@samruthkrishna2947]

What is the symbol you have used for replicating transmission lines in LT spice?

[@FesZElectronics]

There is a dedicated component that comes with the default instalation of LTspice - its called tline

[@visai3634]

I tried to calculate the formula for Rs and Rp , it turns out that Rs = √(Z2^2 - Z1*Z2). Mistakes could happen thought i would point out here. Rp is same as shown in video.

[@bejancornel5224]

Hello, It is possible to model and simulate stubs in LTspice? If it is possible, can you model and simulate stubs in LTspice in future videos? Thank you.

[@FesZElectronics]

Well you should be able to simulate them by splitting your transmission line into 2 pieces, and just add a 3rd line which is not terminated into the junction. But for proper high speed simulations LTspice might not be the best option, you would need a program where you can import your PCB design directly.

[@thezodiace7399]

@@FesZElectronics what type of program can we use?

[@pasha1663]

👍👍👍

[@yveslesage8525]

What is the source impedance (I mean generator impedance) ? None, 50, 75 ?

[@FesZElectronics]

I would say none - there is no dedicated impedance control on the generator output. It might be a few ohm's though because of the generator output stage, but its definitely not 50 or 75.