Questions about fixed impedance matching networks, the necessity of impedance matching, etc.
See also:
- impedance for questions about the general theory of impedance.
- An adjustable impedance matching network is an antenna-tuner.
Questions tagged [impedance-matching]
145 questions
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Does an SWR higher than 1:1 necessarily cause additional heat in the transmitter?
Each of the 3 answers to SWR of 1.5 -- use internal antenna tuner or not? in one way or another suggest that an SWR of 1.5:1 will cause additional heat in the transmitter:
The radio may heat up a bit more during transmit with a 1.5:1 SWR, however i…
Phil Frost - W8II
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votes
2 answers
RF signal level when the antenna is disconnected
This is question a3a1-1 from the set of practice questions in the "amateur radio Exam Secrets" book:
An antenna is connected by a short feeder to the input to a radio receiver. Everything is correctly matched to 50Ω and a sensitive, high impedance…
Pablo Fernandez
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4
votes
1 answer
What kind of losses do you get from an LC network matching the antenna's impedance?
If you have a transmitter that is perfectly on your frequency but you have an antenna with some impedance what types of losses, and of what magnitude, will you expect from a tuner in between your transmitter and antenna?
For example lets say your…
Joshua Katz
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4
votes
2 answers
What is antenna reactance?
I have a V5000 antenna and I’m tuning it but can’t get the Reactance (X) on my MFJ 259B down. Resistance is at 50 ohms, SWR reading 1.2 to 1.3 (I don’t give that much credence) but the Reactance (X) is around 15. Any ideas how to get that down? LMR…
booksbenji
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3
votes
2 answers
Impedance matching: Why do components behave totally differently from theory?
I got stuck with impedance matching for an antenna. Any added components in the matching network gave a result totally different from what a Smith chart predicts. Let me explain this clearer.
First, by shortening L2,C8,L5,C23, I measured my…
Minh Lam
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0
votes
2 answers
SWR reading problems
Hey I'm new to using CBs I have a classic Cobra 29 I had it peaked and tuned supposed to be pushing about 60 watts also supposed to have everything set as far as my SWR however I am still only getting out about as far as I did with the stock radio…
Joe Lee
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How to take to account impedance mismatch losses when cascading 2-port networks as RF System?
I'm trying to learn how to correctly calculate (cascade==RF system cascading) the connection of 2-port networks, taking into account mismatch losses. For example
There is a first 2-port network, its S parameters at 10GHz,
And a second 2-port…
user20113
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