Questions tagged [impedance-matching]
Impedance matching is a process of making one impedance equal to another another.
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When are 1:1 baluns worth it?
I am trying to build an antenna to connect to the GOES-16 satellite (downlink at 1690,1MHz, linear polarization) with my SDR. My plans are using a 1m offset parabolic dish with a biquad feed connected ...
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Eliminate reflections on pulse signal transformer
I am trying to isolate an RLC ringdown signal via an RF signal transformer but I'm having trouble maintaining the signal integrity through the transformer. Below is the simple schematic describing my ...
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Challenges in Bandwidth in Common mode Choke Modeling
I'm currently working on characterizing a common mode choke (CMC). However, I'm encountering difficulties aligning the bandwidth of my model with the measured results. Specifically, when I attempt to ...
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RF output impedance on ESP8684 series
I'm looking for the output impedance on the RF pin of the ESP8684 SOCs.
On other application note like for the ESP32-C3 it mentioned that the output impendance of the RF pin is 35 + 10j.
But for the ...
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HDMI: What is the maximum acceptable differential impedance variation and for which length
Imagine I have a HDMI bus with differential impedance 100 Ohm and length 10cm
Imagine that for a segment of length "L" there is an impedance variation of "DELTA"
Question: in order ...
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When should an unmatched antenna be measured with a cable length in even multiples of a half-wavelength?
A few years ago someone told me that if you use a cable which has a length of an even half-wavelength multiple for the frequency being tested, then the impedance measured at the end of that cable will ...
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Transistor impedance
According to LDMOS transistor AFT05MS031N datasheet at p. 13 " ZSource - Test circuit impedance measured from gate to ground" for 155 MHz is
Z = 4.31 + j.7.54
https://www.nxp.com/products/...
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Function generator impedance matching with an amplifier
I am currently designing an experiment with a material which at low temperatures (below 180K) works like a light detector for infrared. There needs to be a bias applied to the sample which has to be ...
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How do I match the output of a transistor amplifier to 50 Ω?
I'm working on a simple single BJT transistor amplifier to amplify the output from an oscillator for use as a CW transmitter at 7 MHz.
I'm using an emitter follower to provide the power gain, and I'm ...
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SX1262 Matching impedance
I want to build a LoRa node from SX1261 which works on the frequencies of 868Mhz and I found at the manufacturer the following assembly ms I did not find more details on the different passive ...
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Calibrating a VNA
I am using the Siglent SSA3032A-R spectrum analyser which has a Vector Network Analyser (VNA).
Before measuring the impedance of an antenna under test so that I can match this antenna, I have to ...
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Antenna matching using L-sections does not always yield a "matched" solution
I created a program to compute the component values of a T network to match a reactive load (R+jX) to a 50 ohm source, based on the procedure outlined by M. Walter Maxwell in his book "...
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Different trace width signal transmission line
I have a really basic question. I am wondering what happens physically with the signal, if I have a change in a trace width (see picture below).
My point of view is that you have a reflection of the ...
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Impedance matching of a RF power amplifier based on the s2p file
I'm designing the input/output impedance matching circuit for a RF power amplifier, based on the vendor supplied s2p file. I designed separately the input/output matching circuit at the given working ...
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Keep potential difference fixed for transformer's output
I have a source consisting of V1, R1, L1, and L2 to which my load R2 is attached:
For the load, I have 10 or 100 Ohms.
1) R2 = 10 Ohms: Vrms = 315 V, irms = 32 A, P = 10 kW
2) R2 = 100 Ohms: Vrms =...
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