Questions tagged [mixer]
A mixer or frequency mixer is a nonlinear electrical circuit that creates new frequencies from two signals applied to it.
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72 views
BJT Amplifier vs Manufactured RF Mixers
900Mhz Operation
This is a BJT mixer design I found on google
From my understanding in order to use a BJT amplifier as a mixer you have to be in the 1dB compression point.
Question: Am I wrong ?
...
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1answer
46 views
Volume Control for Mixer Circuit using DAC Refence
I am mixing two stereo audio signals together and would like to control the output volume using the (0-3.3v) DAC on my microcontroller. I'm wondering if there is a simple modification I can do to this ...
2
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2answers
205 views
Device to loopback mic to headphones
I have an issue with my headset. I can’t stand not being able to hear myself speak. I’d like to build a passive device to loopback the mic to the headphones that would be plugged in-line between the ...
2
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1answer
55 views
gilbert cell mixer implementation and balun
1) How do I interface LC balun with mixer using differential current RF+ and RF- input signals ?
2) How should I deal with the load impedance (RL) for LO+ and LO- which is almost infinite because it ...
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0answers
56 views
Schematic diagram of a double-balanced Gilbert cell mixer
For the following gilbert cell circuit, I have few questions.
I understand that R1 to R4 as well as M1 to M6 are parts of the double-balanced differential topology which helps to eliminate the DC ...
2
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1answer
151 views
Does a low-pass filter average the higher-order frequencies into a “DC offset”?
In a Pound-Drever-Hall lock, an electronic signal is produced of the form:
We are interested in electronically isolating the term:
My question is: how can we filter to get exactly this term (listed ...
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1answer
19 views
Conversion Gain Definition for DSB-SC Upconversion
If I multiply a baseband signal \$A cos(C\omega t)\$ and a carrier signal \$B cos(D\omega t)\$, the result is \$\frac{AB}{2} [cos(C-D)\omega t+cos(C+D)\omega t]\$, which is a double sideband, ...
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2answers
220 views
Converting a headphone output to line level
I have a guitar amp that has a headphone output.
I would like to convert this signal to line level so I can use it in a small mixer along with other line level signals to be heard in "in ear" style ...
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0answers
21 views
ADS harmonic balance discrepancies with sawtooth waveform
I am using ADS for a simulation where I am biasing a diode with a sawtooth waveform.
The sawtooth source provided by ADS, and 3 harmonics are specified
There are different phase delays across the ...
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1answer
55 views
Can you make an electric gamma ray emmiter by adding up frequencies with freq. mixers up until you reach gamma ray herz quantities?
I just thought this up. Theoretically if you can add freq numbers you can get to large quantities like in a calculator, only this time mixing electric frequencies using amounts of circuitry right? Is ...
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0answers
45 views
Appropriate driver amplifier to amplify an FPGA pin voltage for RF applications
I'm trying to built a nanoseconds RF transmitter using an FPGA and an up-converter.
However I don't know the correct configuration (I prefer a single IC) in order to drive a nanosecond pulse (pulse ...
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2answers
83 views
I need to keep one of my input signal of my mixer intact
I'm currently working on an audio circuit.
I'm using a simple mixer to mix two audio signals together. It works well enough for now.
Here is the circuit :
simulate this circuit – Schematic ...
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2answers
119 views
Mixing analog audio signals with resistors
I am creating a type of mixer for 2 audio inputs into 1 output so i can use 1 pair of headphones with 2 computers without buying an expensive mixer with a amp
Currently i have 1k 1/2W metal resistors ...
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2answers
97 views
Hardware audio mixing [closed]
I'm having a hard time trying to understand some basic sound engineering concepts.
From https://en.wikipedia.org/wiki/Original_Chip_Set#Paula:
Paula has four DMA-driven 8-bit PCM sample sound ...
2
votes
1answer
371 views
Gilbert cell. Understanding the basic
I am trying to understand a concept of Gilbert cell.
I have the next figure.
Quastion1:
If +1V is set up in (3), then in (4) is admitted -1V, and for (5) is -1V, (5) +1V.
The current source is sume ...
2
votes
1answer
303 views
Explanation of 3 Tone Control Circuit
I'm building an analog drum machine and want to have a 3 tone control circuit to individually adjust the bass, midtones, and treble frequencies on each of my instrument channels.
I thought it would ...
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0answers
32 views
2 tone test with RF mixer
I am designing a system that uses RF to probe the nonlinearity of a target. It works as follows.
Transmitter sends out 2 RF frequencies, such as 900 and 910MHz.
The target/reflector has a ...
1
vote
1answer
92 views
Double Balanced Mixer - Microstrip Design: Realization
I have a question about the realization of a ring mixer with 2 balun elements in microstrip design:
The problem I see is that either the microstrip lines or the diodes cross each other.
I have found ...
2
votes
3answers
91 views
How can guitar pickups hot leads be wired in parallel without causing current problems?
I am looking up wiring diagrams for electric guitar pickups and noticing that the common method for combining two pickup signals is just to have a switch that can optionally have both the hot leads ...
1
vote
4answers
201 views
How to amplify RF signal to high enough level for a CMOS downconverting mixer?
I've been reading original academic papers on mixers and now a RF textbook and I have been unable to understand a very basic thing, which is how do I get a RF signal, say -65 dBm, at a high enough ...
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vote
3answers
359 views
Gilbert cell biasing
I'm new here so I'm going to make is as simple as it can get..
How can I bias a Gilbert cell with bjt transistors like this one:
What methods can I use to bias the transistors? Is there any example ...
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1answer
52 views
Harmonic mixing in spectrum analyzers
I'm having a pretty difficult time understanding how tuning works when using harmonics in spectrum analyzers. I'm reading about the topic from Keysight's AN 150.
Question 1
The following plot is ...
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2answers
94 views
How do multiple mixing stages work in a spectrum analyzer?
I'm reading about spectrum analyzers from Keysight's AN 150. On page 12 they explain how multiple mixing stages are used to obtain narrower IF filters. The block diagram offered is the following one:
...
4
votes
2answers
1k views
How does tuning in a spectrum analyzer actually work?
I have a pretty basic doubt about how tuning works in spectrum analyzers. I'm reading about the topic from Keysight's AN 150.
The problem arises in this paragraph in page 11:
We need to pick an ...
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2answers
88 views
How do I create a subtractive or dffferential two channel audio mixer?
I have a desktop mixer made by Behringer (Xenyx X2222USB although I am not using its USB capabilities) which has a line level output that feeds 2 channels of a Behringer USB audio interface (U-Phoria ...
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3answers
198 views
Are there any drawbacks to this oscillator frequency multiplier circuit?
I'm trying to make an upconverter from 65 MHz to UHF band using a mixer; I therefore need an oscillator frequency around 375 MHz to mix with the 65 MHz base signal. I'm also trying to vary the ...
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1answer
34 views
Mixer datasheet plots
I am trying to read datasheets of mixers...
For the plots in datasheets, for example Conversion Loss/Gain vs frequency, is that frequency RF or LO?
Analog Devices labels the x-axis as RF frequency ...
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0answers
124 views
When to bias diodes in double balanced ring mixer?
Do I need to bias up the didoes in a double balanced ring mixer?
Some diodes have turn on voltage at 0.3V, and some turn on at 1.2V. If LO power is about 5dBm (~0.6V peak voltage), I would need extra ...
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1answer
182 views
What is LO rejection in a mixer?
Could anyone please tell me how LO rejection is defined in a mixer? I've heard Image Rejection but not LO rejection.
Please help!
Thanks.
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0answers
48 views
Diodes for mixer design
For a diode ring mixer, how should I choose the types of diodes? I've seen Schottky diodes as the primary choice. but why not PIN diodes?
What diode aspects should I consider when designing a mixer? ...
1
vote
1answer
519 views
Headphone amplifier for guitar with stereo MP3 input - mixing
I'm building a practice amplifier for my girlfriend who is learning to play the bass guitar. I'm a reasonably experienced electronics builder so building something to plug a guitar and headphones into ...
2
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2answers
277 views
RF mixer theory and short circuits
Suppose I have the following RF mixer circuit-
How does placing two AC voltages of differing magnitude and frequency directly in contact with one another not create a short circuit condition in a ...
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0answers
39 views
How could i mix preamp output with line in signal?
I want to do simple karaoke circuit. I have ~600 ohm(DC resistance) dynamic mic and a TL07x op amp (on a 24v SINGLE rail DC supply). I need to mix its MONO output with some line in STEREO signal (lets ...
3
votes
1answer
384 views
Usage of the Mixer as a variable attenuator
In several user manuals for RF mixers (double-balanced), it is stated that the mixer can be used as a variable attenuator due to the fact that the RF-LO isolation is related to the amount of the DC ...
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1answer
309 views
Mixing down to base band
What exactly is the base band? I always thought that it is a synonym to intermediate frequency but it appears not to be the case.
For example I have Bluetooth signals in the range of 2.4 to 2.48 GHz. ...
3
votes
1answer
1k views
Multiple Options for Passive Audio Mixer
I have two mono audio inputs that I need to passively combine into a single output. Both inputs have built-in volume controls so I don't need any volume control in the mixer. I've been looking at ways ...
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2answers
457 views
Subtracting One Frequency From Another
I would like to subtract one frequency, varying from maybe 40kHz to 41kHz, from a 40kHz signal, to end up with a signal from 0 to 1kHz. Right now the 40kHz fixed signal is square and the variable ...
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1answer
201 views
Line level detection using ADC from a passive summing box
I was looking for a way to detect a line-in device transmitting audio.
I got the idea to use ADC for this from this question:
How to detect line level audio signal?
I already have a 4-channel ADC (...
1
vote
0answers
121 views
Switching Inputs on Audio Mixer
I am experimenting a bit and have built the circuit shown below to mix two input signals. It works great across the full audio spectrum.
Now I’m trying to figure out a way to switch the signals so ...
0
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1answer
90 views
fader not fading? [closed]
I have a small, inexpensive mixing board that has been through some moderate wear. The individual channels and various controls work, except that the master fader only affects the volume of the right ...
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0answers
233 views
Diode ring mixer (difference between strong and weak LO)
I've built a simple diode ring mixer according to this video. The mixer works, checked it on several frequencies. The application of the mixer is to isolate the IF from a 27 MHz FSK signal. As my LO ...
3
votes
1answer
67 views
How do I reuse the LO when designing a loopback receiver?
Suppose I'm designing a transmitter which has an LO and an IQ mixer. I would like to shift the LO down by 100 MHz or so, so I can mix it with the IQ mixer output so I can monitor the IQ mixer balance ...
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0answers
94 views
reduce power consumption on this audio mixer
I'm wondering if you can reduce the mA consumed by this discrete audio mixer (on both +12V and -6V) by changing the resistors values, but keeping the same functionality (same gain, same asymmetrical ...
2
votes
2answers
314 views
How to make mix mono into stereo audio
I am trying to mix a mono microphone into both channels of stereo audio. The output of the microphone amp is yellow. The stereo in is red. I am using 2 schottky diodes in order to mix. Is this an ...
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0answers
93 views
Forking DAC output
I am designing circuit based on stereo UDA1334BTS. The audio output should go to two inputs - 3.5 mm jack line out, and to internal appliance's mixer/amplifier.
The issues here are:
I have no idea ...
2
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0answers
226 views
Why are only 3 pins connected on a dual gang pot? [closed]
First post on this platform... I am wondering if anyone knows why in some DJ Mixers (e.g. Pioneer) which use dual gang pots for channel faders, only 3 of the 6 available pins are connected. Also, ...
2
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4answers
1k views
Why can't this mixer be built with two resistors?
Disclosure: This is for the MIT Circuits MOOC on edX.
The task says build a circuit such that Vout ~= 1/2 V1 + 1/6 V2. Now I understand the solution, which uses three resistors.
However, I'd like to ...
13
votes
3answers
4k views
Accidentally downmixed stereo to mono, why does this work?
I have a cheap Chinese Bluetooth audio amplifier like this:
It has four screw terminals for the speaker connections, namely L+, L-, R+ and R-. I accidentally connected a single speaker to L+ and R-, ...
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3answers
527 views
How do I integrate multiple IC circuits for audio?
My primary concern here is the correct way to apply power (and grounding) to an assortment of single and dual-supply ICs in a mixed environment for an audio application.
I constructed a portable ...
6
votes
5answers
3k views
Audio summing mixer- inverting or non inverting output?
All the audio mixer circuit examples I see online are based off of the summing amplifier:
This is an inverting op amp configuration so the output is inverted. I built a similar circuit and I couldn't ...
