Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [attenuation]

40 questions
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Probing 50 Ω antenna output with oscilloscope

I would like to see the signals that I am picking up and I have a DSOX1102G oscilloscope. My probe has a switch that says 10x and 1x. I have built a 1/4 wave VHF monopole antenna out of a SO239 connector (made to pick up broadcast FM 88 MHz to 108…
Yousif Alniemi
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Why is an oscilloscope's Attenuation switch placed on the probe?

I'm wondering why an oscilloscope's Attenuation switch is placed on the probe not on the oscilloscope's body (like the AC/DC Coupling switch that's placed on the scope body not on the probe)?
M.A.K
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Convert 'dB per 100m' to 'dB per 1m'

I want to know about wire loss per meter. However, in the datasheet, it is written that 6.1 dB is attenuated per 100 meter, so I wonder if it is possible to simply calculate 0.061 dB if I want to calculate with 1 meter. If it is possible or…
journey
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Measuring signal attenuation between two antennas

I am new to HF design and have some problems. I am trying to measure how a signal is attenuated between two antennas and compare the results with theoretical values. I have two antennas which are placed at distance of 1 m. One antenna is connected…
zulunation
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High output impedance piezo guitar pickup is better attenuated by a shunt capacitor than an inverting opamp attenuation circuit

The circuit below is meant to attenuate a high output and high output impedance piezo electric guitar bridge pickup -7 dbV. The circuit models both the pickup output impedance and load of the cable capacitance with amplifier input impedance. In…
p-we
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Running baseband analog audio signal over cat 5 cable

What will happen to a single ended (not differential) 1Vpp analog audio signal(4khz bandwidth, not modulated) if it runs through long cat5 cable (length can be 50 meters)? How much signal voltage can drop? Can there be any change in frequency? What…
adeel asif
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4th-order Butterworth filter - strange oscillation in output

I have created a 4th-order filter based on the result of calculations and simulation. Bellow is schematic: In simulation the filter works fine (I also checked the transfer function using this online tool) but in the real world, it doesn't. I use a…
grandzello
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6 dB in-line 50 ohm attenuator

Recently someone posted a question regarding an inline device to attenuate their voltage on a 50 \$\Omega\$ coax by half (i.e. 6 dB). Because the question asked for commercial recommendations, it was closed. However, the question of how to create an…
Math Keeps Me Busy
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Instrumentation amplifier output attenuation in LTSpice

My task was to design an instrumentation amplifier with given specifications and simulate it on LTSpiceXVII. We were told to only use one type of ac source, so to get the inverted signal I used a simple inverter design with unity gain. However, I…
eren_y2509
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What's the noise figure of an attenuator not at room temperature?

I'm confused by the following: What's the noise figure of an attenuator with 10 dB loss at very high temperature, having a noise power of like 80 dBm/Hz? How about if the attenuator at very low temperature having a noise power of -500 dbm/Hz? The…
Xin
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Difference Amplifier - Signal Attenuation

I am planning on using a difference amplifier IC much like the AD8206 to measure the differential voltage across a high side shunt in order to monitor the current. I chose a differential amplifier over a current sense amplifier (CSA) IC because its…
Tim51
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Instrument level to line level and mixing

I would like to convert an instrument level (guitar) to a line level in order to feed the isd1820 sampler chip. What are my option in order of doing so? In addition - I would like to mix the four isd1820 outputs (see my schematics) Using the lm358…
lon_ly
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Attenuation in current booster circuit with op-amp

I was testing a current booster circuit in Multisim with a TL081IP when I noticed that I'm getting high attenuation at surprisingly low frequencies (above 1 kHz). The circuit and the frequency response is shown below: From my understanding, I…
João Marques
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Effect of a capacitive or inductive divider on noise

I am used to thinking about the effect of an attenuator on a system's noise in the following way: there is some system noise (and signal) at the attenuator's input, coming from the preceding part of the circuit this system noise is attenuated by…
janizer
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Calculate the frequency corresponding to a given current or power attenuation in an LRC circuit

For a series LRC circuit, I'm trying to calculate the frequency corresponding to a given current (or power) attenuation to either side of the resonance frequency peak according to the formula for current: $$ I = \frac {V_{rms}}{\sqrt{R^2 + 2\pi FL -…
Ted Jackson
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