Questions tagged [tuning]
The tuning tag has no usage guidance.
27
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Analog television: What is the difference between the first IF and second (demodulated) IF?
I am trying to understand what kind of changes occur to a signal in the chips which sit between the tuner and, for example the FM audio demodulator.
Take the attached example - the TDA2546A. It takes ...
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0
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1
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91
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Resonant RF transformer using a piece of wire (no capacitors)
I'm curious if it is possible to build a spark-gap Tesla coil without using capacitors at all.
Basically, treating the primary and secondary as TX/RX antennas and cutting them to proper length so that ...
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49
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VCO tuning voltage range starting from higher than 0 V
I have seen some VCO datasheets. In every datasheet, I see that the tuning voltage range starts from some value above 0 V (like 0.5 V, 1 V etc). So, what would be the frequency at 0 V? And why do they ...
- 49
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4
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Difference between tuning and matching for transmitter/receiver circuits
I would like to find a coherent answer to following question:
What is precisely the core difference between tuning and matching in HF electronics, especially in design of transmitter/receiver circuits?...
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41
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Tuning the resonance frequency using varactors in a RCL circuit (and how to avoid noise)
I'm a physics student trying to run a few simulations on a RCL circuit. I don't have too much experience with electronics and could use some help on some basics on how to tune the resonance frequency. ...
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1
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49
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DDS - find optimal size for LUT, PHACC and sampling freq for application
I had the following question.
About the topic of DDS you can find a bunch of information on the net and i think i understood the basics relatively well.
You use a lookup-table with stored values of ...
- 3
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3
answers
124
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Old tvs, how did storing settings work, and what changed in the tv when we tuned a channel?
I don't have an EE background, but I would like to understand some aspects of old TVs.
When we tuned channel what exactly changed inside the tv. Was there a circuit card in the tv where something ...
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140
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How does one choose a resistance for an AM radio antenna receiver tuner?
[![enter image description here][2]][2]
I am using some pretty rough, brute force and novice calculations, so if anyone knows a nicer method I am happy to learn.
I want to build an AM radio receiver ...
0
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2
answers
301
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Variable Capacitor - capacitance vs. rotation angle
I have an Elenco AM / FM radio kit. For the AM section I am trying to figure out the relationship between the frequency shown on the calibrated dial and the angular position of the dial.
For a ...
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Calculating lengths of single-stub transmission line when all 3 characteristic impedances differ
Consider a transmission line circuit like the following but where \$Z_{o2}\$ was also unique (say \$Z_{o2}=7\,\Omega\$):
I know how I would find \$l_1\$ and \$l_2\$ using smith charts:
$$Re\left\{Y_n(...
- 155
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131
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How to design a PI controller for fourth-order transfer-function?
Fourth-order systems may render very complex characteristic equation that are difficult for tuning. Is there any method to tune controllers for these systems easily?
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Why do AM radio stations have secondary frequencies?
First thing I'm sorry if this question sounds too much beginner-ish. I don't major in electrical engineering so I may lack the basic knowledge.
I have been noticing that, while tuning my AM radio, ...
- 151
0
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2
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174
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Antenna Tuning for Source Impedance not equal to 50 Ohm
I have designed a setup for 433.92MHz wireless device (a key fob). The source impedance is not equal to 50Ohm. The load impedance may or may not be 50Ohm depending upon the choice of the antenna. For ...
- 141
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28
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RC quality factor increase
simulate this circuit – Schematic created using CircuitLab
This circuit has a bandwidth of 0.9Hz but I want even lower bandwidth.
I have this RC tuning circuit. If i had an RLC tuning circuit ...
1
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0
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50
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Tuning PID Controller with high precision
I'm learning control theory at university and I have to design PID controller for this object
G(s) = 10/s(s+1);
But my teacher requires settling time <10s and %overshoot <=2%
Anyone can suggest ...
- 13
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2
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137
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Antenna Tuning for a Multi-band Antenna
I have PCB antenna . which support multiple band antenna.
https://www.johansontechnology.com/datasheets/0830AT54A2200/0830AT54A2200.pdf
we also have tune circuit before antenna as recommended by ...
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1
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225
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RF Jumper at 2440MHZ
I need a series component to isolate a 2440MHZ antenna for testing purposes-- it can either be a a high quality 0402 RF capacitor (Johansen) or a zero ohm resistor.
The series component will remain ...
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3
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197
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Radio tuning capacitor
In a radio tuning capacitor that consists of semicircular plates , are the plates connected in series or in parallel ?
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417
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Antenna tuning & impedance matching, do i need to connect the IC?
I want to make a pcb rf trace to use it as an antenna, for a bluetooth IC. I have already studied the basics of impedance matching and antenna tuning, smith chart and antenna clearance.
The specific ...
0
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258
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Can I replace the transistor in this circuit (Esaki oscillator) with a Zener diode?
Can I replace the transistor in this circuit (Esaki oscillator) with a Zener diode?
1
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1
answer
92
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Do algorithms exist for tuning microwave filters?
I'm a systems engineering student and I have taken a summer job at a company that manufactures various microwave filters, my role is to "try" improve and standardise their processes in order to ...
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2
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My antenna tuning component values worked on a fresh board previously. Now they're not working. What could be causing this?
This is one of those hardware questions that's making me bang my head against a wall.
About six weeks ago I spent a day tuning the NFC antenna on my board. I ended up using ~71pF of shunt capacitance ...
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28
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Finding the gain difference for a ultrasonic assembly
I am tuning an ultrasonic assembly for a welding application and tuned the system to operate at 41kHz according to the oscilloscope. The transducer operates at 40kHz, when calculating the gain with ...
- 273
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697
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Where to connect the VNA during matching network tuning
I'm trying to design the matching network between an antenna and its transmitter, running at 868MHz, as shown below. There's probably about 20mm between the transmitter output and the Pi network.
...
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57
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MOSFET Switch for Tuned LC Tank
I am trying to implement the circuit as shown below.
I essentially want to be able to control the gate voltage of the NMOS to change the resonant frequency from 5GHz to 2.5GHz. For a transistor size ...
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388
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Magic Eye Tuning Tube Variable Negative Voltage
I am thinking about several applications of magic eye tuning tubes as display pieces and had a question about their operation. I have attached a sample circuit from a datasheet for an EM84 tube. I ...
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Some questions regarding impedance matching and tuning
For maximum power transfer in a circuit impedance matching is performed:
Similarly from the transmitter antenna to the receiver/load one can think the total impedance from antenna to the receiver as ...
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