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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1answer
144 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
17 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
47 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
19 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
54 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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41 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
73 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 ...
0
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2answers
86 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
85 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
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1answer
292 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
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1answer
218 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
29 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
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1answer
70 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
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3answers
88 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 ...
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4answers
174 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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3answers
268 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 ...
0
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1answer
50 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
92 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
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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 ...
0
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2answers
83 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 ...
2
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3answers
162 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
108 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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0answers
190 views
diode ring mixer matching
I'm testing upconverting and donwconverting a DSB-SC signal using two diode ring mixers in a fixture that connects both mixers with a matching network.
The first mixer has 81Mhz at LO, 100kHz at IF ...
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1answer
168 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
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1answer
447 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
253 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
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1answer
338 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 ...
0
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1answer
269 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
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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
409 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 ...
0
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1answer
179 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
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0answers
118 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
81 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
219 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
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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
92 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
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2answers
296 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 ...
0
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0answers
90 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
182 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, ...
3
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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-, ...
0
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3answers
505 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
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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 ...
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votes
1answer
144 views
Spectrum analyser [closed]
Why do we use ramp generator (sawtooth generator) with local oscillator in a spectrum analyser?
I have searched in Google and I didn't find any answer that made me understand the concept.
Thanks !
0
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3answers
329 views
Mixer spurs and IF output filters
I'm designing a simple diode ring mixer for down-conversion from 1.5G to 200k. I want a band-pass LC pi-filter on the mixer IF output.
I've designed the filter for 50R source and load impedance by ...
1
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1answer
382 views
How does this transistor radio mixer work?
I recently picked up a transistor radio, a Unitra Nova 206. I've been studying the schematic with an interest in the AM operation for now. Most of it makes sense and I've included an annotated ...
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3answers
160 views
Are electret microphones frequency mixers?
I wonder if common electret microphones are frequency mixers. That is, say, when two signals pass through the diaphragm, will two new signals f1 + f2 and f1 - f2 be produced if the sound pressure is ...
