Questions tagged [amplifier]
Questions about amplifiers, typically RF power amplifiers. For low-noise amplifiers (LNAs) consider using the "lna" tag.
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Why does "high SWR" damage transmitters, instead of "impedance mismatch"?
In the audio realm, where cable lengths are insignificant compared to the signal wavelength, I would understand an impedance mismatch damaging an amplifier as follows:
Take an audio amplifier that ...
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What is a linear RF amplifier?
Most of the RF amplifiers advertised, and most of the questions about amplifiers, are "linear" amplifiers.
What is a linear amplifier, and what other common amplifier type(s) exist that requires ...
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What is the average fade margin required for proper operation at 2.4 GHz?
I have two radios. Sensitivity is -84 dBm and transmitting EIRP is +30 dBm. How much distance should I expect?
I want it to be somewhere near about 2-3 km. Is it possible?
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What is the purpose of the transformer at the input (and output) of this RF push-pull amplifier
Firstly, feel free to move this to Electronics SE if it's not on-topic, but it's strongly related to ham radio and RF circuitry.
Reading Hayward's classic "Solid State Design for the Radio Amateur" ...
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How to calculate if low-pass filtering is sufficient?
An answer on this question Suggested method for boosting 0.05 watt transmitter up to 10+ watts? suggests putting a filterless 19dB amplifier between the HackRF (or similar general-purpose SDR) and a ...
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Efficient BPSK31 amplification
I'm looking at making a portable system that can transmit BPSK31. I have a limited power budget, so I'm looking at trying to make my final power amplifier as efficient as possible. From my ...
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Suggested method for boosting 0.05 watt transmitter up to 10+ watts?
Long time ham operator here, new to this particular challenge -
I have a software defined radio transceiver that I'd like to try and use to make contacts on HF, in particular 20-meters. Tuning ...
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Why does an RF Amplifier fail when the SWR is high?
Exactly why does an RF output transistor fail if the SWR is bad ?
Is it A because the impedance mismatch between the transmission line and the antenna results in maximum power not being transferred ...
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Reduction in transceiver power output into high SWR
How much do transceivers drop their output power, when the SWR is high?
Most amateur solid state amplifiers or transceivers are (fully?) protected against high SWR, by a circuit which reduces the ...
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How does the Maximum Power Transfer Theorem relate to RF power amplifiers?
The Maximum Power Transfer Theorem says that maximum power transfer occurs when the source impedance equals the load impedance, when the power transferred to the load is 50%, the other 50% being ...
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RFID extension cable
I am trying to build an extension cable to relay an RFID signal (125kHz) to various distances (2,5,10m). I am using 2 identical antennas at the two ends of a 75Ohm coax cable, and I also put 2 ...
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What safety procedures should be followed when developing and testing a high power amp?
I'm designing a 300W power amplifier using the MRF300AN from NXP targeting a center frequency of 146 MHz.
Obviously I need to keep my fingers out of it and test into a dummy load, but generally ...
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What's the maximum possible "DC input to radiated RF" energy efficiency of a radio transmitter system?
It's simply a bromide amongst hams that you need to match the output impedance of a transmitter to the input impedance of an antenna, but I never thought through the implications of this until I came ...
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S-Parameters Power amplifier impedance matching
I recently decided to conceive a 10W class 446MHz amplifier.
I want to be able to amplify a 100mW signal into a 10W, for that i'm going for a two stages amplifier :
SKY65162 to amplify the signal to ...
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Toroid Coupling Issue in Common-base Amplifier
I'm working on an old school VFO for the 15 meter band based on a JFET Hartley oscillator. The plan is to follow the oscillator section with a JFET buffer, then a CB amplifier (for increased reverse ...
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sdr as watts and amps [closed]
Thanks to rclocher3 for helping edit more to English
why closed
so
my struggle to get thought to English
thank rclocher3
I round back too
best I put
in avuenue what I was asking
why closed
i tryed
...
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