Questions tagged [rf-power]
Questions about power ratings and restrictions, including maximum power by law or for certain components, or about calculating power in certain situations.
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BAS70H rf detector output level
My project is to build my own swr and power meter, with an ESP32. uC has 12-bits ADC under 3.3V (sensitivity should be about 800uV)
A friend of mine (Pierre, F1FDD) had the idea to make the HF coupler ...
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RF Coax Termination Question
I am looking to terminate a line with the below characteristics and having a hard time locating an RF coax terminator. Can anyone help?
I have an FPGA HW that is feeding multiple receivers. The input ...
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What is the antenna design and gain for the WA1 U/V band antenna on the ISS?
My son KJ7NLL is working to contact the ISS using an antenna we built together, and we were wondering the approximate minimum transmission power to reach the ISS. If I understand correctly (and ...
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Low power indicated on tuner
Please forgive my extremely basic question, I am brand new on HF and have issues with my setup.
I have a Chameleon MPAS antenna in vertical configuration connected to an AT-100 ProII tuner with a 50 ...
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Waveguide size for 2.4 GHz
I'm thinking to make a wave guide that has diameter 1/8 of the wave length.
At 2400mhz the full wave length is about 125mm.
I have aluminum pipe that is 16mm. So 8*16 = 128mm (very close to 125mm).
If ...
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What happens with LNA in bidirectional communication? [closed]
I want to ask that if you have a cable that has started with 40dbm source signal and has reached -10dbm then you put LNA (the end of the cable will be plugged to RFIN), then attach the RFOUT to ...
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Coaxial cable loss, dbm, db correlations
I am very confused how ham operators deal with all this, because most of the information in internet is controversial.
I have coaxial cable with loss of 34dB at 100 meters at 2400mhz.
People say that ...
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What this E(EL) symbol does mean?
I can't understand what this E(or EL) symbol does mean. I know that Zo means impedance and I can calculate trace width according it, but what E symbol does mean?
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Extracting radio signal strength from multiband TIFF file
I have N number of TIFF files corresponding to each radio stations in my data, and I am trying to measure the approximate signal strengths from each of these stations at K geographic locations(say for ...
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How do you protect your radio when testing custom RF circuits at ~100W?
We are designing a UHF/VHF diplexer for a satcom project and targeting support for 100W. Our radio can transmit near 100W but of course we want to protect it in case there is a failure of some kind.
...
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How do you choose an inductor wire gauge for high-power RF?
At 100 watts in a 50-ohm system, the current flowing through an inductor would be about 1.41 A, thus a 26-AWG wire should be plenty since they are chassis-rated for 2A and for just a few windings that ...
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Why measuring Voltage and Current becomes difficult at Microwave frequencies? Why measure Power?
I have been reading some Classic books viz. Techniques of Microwave Measurements - Carol Montgomery, Foundations of Microwave Engineering - Collins, and some other google searches and they all claim ...
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Does ERP power depend on transmitter duty cycle?
I’m building a transmitter and I’m trying to stay under the ERP power limit of my country , which is 0.5 Watt at the frequency I’m working on .
I was thinking about increasing the transmission range . ...
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Ferrites losses calculation
I am new on RF design. I would like to know more about ferrites. I am looking for information about how to calculate ferrite losses and saturation points for a given application. I also would like to ...
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Design of an LNA housing box for a UHF/VHF satellite ground station
I'm currently designing a waterproof metallic case to house LNAs, power cables, and RF switches for a UHF/VHF satellite ground station. As shown in the diagram below, the antennas are connected to an ...
