Hi there I have a charge amplifier, used to amplify the signal from a piezo electric transducer, with 2nF of reference capacitance shunted...

Hi there I have a charge amplifier, used to amplify the signal from a piezo electric transducer, with 2nF of reference capacitance shunted with 1GOhm. I need to be able to reset the amplifier, preferably with a solid state device (the circuit has to be very compact, and operate in a high-vibration environment). One possibility which comes to mind is to simultaneously short the amplifier ou...

I read this post in an antenna group and I don't get how this guy is coming up with a negative noise figure. Looks to me like he is...

I read this post in an antenna group and I don't get how this guy is coming up with a negative noise figure. Looks to me like he is calculating the noise figure of a resistor, not the amplifier. Anyone care to explain this to me? The part that seems bogus is this... > The negative NF is defined as the amplifier noise being less than the > increase in noise due to the amplifier gai

Anyone have an off-the-shelf 2.2-2.4GHz amplifier they like? ~10W is what I'm after. Mini-Circuits has their ZHL-30W-252+ which would be fine,...

Anyone have an off-the-shelf 2.2-2.4GHz amplifier they like? ~10W is what I'm after. Mini-Circuits has their ZHL-30W-252+ which would be fine, although at $3k I'm continuing to do a bit of searching... (And before anyone asks, no, I'm not building a high-power WiFi amplifier and, yes, I do have the appropriate FCC license to put this thing on the air -- with various restrictions on t...

Hello, I'm trying to make a voltage controlled amplifier. I only need a gain of about 11 max. So I thought I would use an opto as a variable...

Hello, I'm trying to make a voltage controlled amplifier. I only need a gain of about 11 max. So I thought I would use an opto as a variable resistor on an inverting amplifier. I went with the H11F3M https://www.fairchildsemi.com/datasheets/H1/H11F3M.pdf I built up the Automatic Gain Control circuit in the datasheet. I used a 50k resistor as my feedback resistor. When I fired it up, my...

Is it possible to calculate the amplification factor for an amplifier,, e.g., a common emitter amplifier. This is because the amplification...

Is it possible to calculate the amplification factor for an amplifier,, e.g., a common emitter amplifier. This is because the amplification depends very much on the biasing condition, and so without a SPICE simulation, it appears impossible to determine the amplification factor. Am I right/wrong.

Could some electronics guru here shed some light on this Could a single stage common collector amplifier exhibit amplitude modulation ? I have...

Could some electronics guru here shed some light on this Could a single stage common collector amplifier exhibit amplitude modulation ? I have the SPICE model of a simple common collector amplifier consisting of two base bias resistors, a collector resistor and an input and a output DC blocking capacitor, as well as a source and a load resistor of 50.0 Ohm. The BJT collector is connected to ...

I'm simulating on LTSpice, a simple amplifier circuit with a 2.5V offset, but if I don't include a capacitor on my input my output hits the...

I'm simulating on LTSpice, a simple amplifier circuit with a 2.5V offset, but if I don't include a capacitor on my input my output hits the rails... why is this? The link shows what I'm doing in LTSpice thanks http://i555.photobucket.com/albums/jj477/panfilero/Capture-1.jpg

The radio kit hasn't arrived yet (Thread of 18th Jan. Probably due to weather conditions here in Ontario) so I thought I'd try my hand at making...

The radio kit hasn't arrived yet (Thread of 18th Jan. Probably due to weather conditions here in Ontario) so I thought I'd try my hand at making my own audio amplifier kit. The requirements were as follows: 1. Must use components I already have. I couldn't find any 1N4148 but did find packets of 1N4001 so that's what I used. Also I could only find one resistor under 1 ohm so another is...

Hello guys.. I want to design a trans-impedance amplifier to detect currents of the APD (in the range of 200 nA to 100 micro A). Could some...

Hello guys.. I want to design a trans-impedance amplifier to detect currents of the APD (in the range of 200 nA to 100 micro A). Could some one suggest me the best IC with less bias current, single supply (+5 V only) and how to design a high sensitive TIA..? (typically, for every 100 nA change in the current, 100 mV voltage should be displayed).

I'm not an analog design expert, but needs must. I recently adapted a Doug Self audio amplifier design for use on a 60V single supply, and to...

I'm not an analog design expert, but needs must. I recently adapted a Doug Self audio amplifier design for use on a 60V single supply, and to go up to 100kHz with a working ambient temperature of -20'C to 180'C. I can't show the circuit, but it was based on Fig 1a here... http://www.douglas-self.com/ampins/dipa/dipa.htm Cdom needs to come down for this higher frequency application, b...

Hi I need to measure a load on 14V line, using say 10 (or 100) milli-ohm resistor. I want to get an output like 0-4V for 0-4A load. A small...

Hi I need to measure a load on 14V line, using say 10 (or 100) milli-ohm resistor. I want to get an output like 0-4V for 0-4A load. A small offset of 1V is acceptable. Even 0-2 or 1-3 or 0-8V for the load is acceptable. I have an op-amp working on 12V. I have been calculating on a differential amplifier. I am limited, that I need to divide the 14V to at maximum 11V or even 10 to be withi...

This app came with the yoke-style sound amplifier I bought, but it seems to work with a cell phone and earbuds too, and though it's not what...

This app came with the yoke-style sound amplifier I bought, but it seems to work with a cell phone and earbuds too, and though it's not what an audiologist would do, IMO it's pretty good, and easy, and includes more than I would have espected** you don't have to buy the sound amplifier if you don't want, though I've included the link **It tests hearing at iirc 4 frequencies and goes up and ...

Greetings people ! So lately, I have been working on my Sigma Delta ADC and before going advance, I wanted to have a base model WORKING (1ST...

Greetings people ! So lately, I have been working on my Sigma Delta ADC and before going advance, I wanted to have a base model WORKING (1ST ORDER, 3 bit digital output) . The circuit is quite simple. Input (x) -> Difference Amplifier -> Integrator (op-amp) -> Quantizer-> Encoder -> 3-bit Output (Y) -> Feedback DAC to the non-inverting pin of Difference Amplifier (I am using I

Hi all, Someone at work wanted a buffer to drive a coax cable with a signal from a high impedance device. I thought this would be a quick job...

Hi all, Someone at work wanted a buffer to drive a coax cable with a signal from a high impedance device. I thought this would be a quick job so I built a buffer amplifier, using half of an AD8066 configured as a unity-gain buffer. I know that op-amps don't like capacitive loads, so I connected a 50 Ohm resistor between the cable and the buffer amplifier and also terminated the other ...

I was looking over the schematic for the Roland Jazz Chorus amplifier, and the power amp section seems pretty standard, except for the fact...

I was looking over the schematic for the Roland Jazz Chorus amplifier, and the power amp section seems pretty standard, except for the fact that the designers apparently chose to use a "PNP" configured Sziklai pair as the bias voltage source, to set the quiescent current in the output devices (biased into class AB I'd guess.) Bottom right: http://tinyurl.com/h4jnsg2 Any ideas as t...

Hi, I want to measure very weak piezoelectric signal from a quartz crystal dete= ctor that mechanically vibrate. Although I can simply...

Hi, I want to measure very weak piezoelectric signal from a quartz crystal dete= ctor that mechanically vibrate. Although I can simply measure the output using a preamp, such as SRS 560, i= t seems I will need a "trans impedance amplifier" to convert the current si= gnal to voltage signal, in order to provide a virtual ground and avoid load= ing the detector, if my understanding is right...

Dear All, I am now making a 48 V to 120V Boost Converter (with a single series 560uH 10A inductor) using PWM IC SG3524, and I am a little...

Dear All, I am now making a 48 V to 120V Boost Converter (with a single series 560uH 10A inductor) using PWM IC SG3524, and I am a little bit confused with the use of error amplifier input pins (pin 1 and pin 2) and the compensation pin (pin 9). A typical example application circuit (see figure 13) divides the reference voltage 5V to 2.5V, and feeds it to pin 2 as reference. The output is ...

Here's a TIA circuit published in 2012, in RSI, by Yale physicist, Stephen Eckel. ?A high dynamic range, linear response transimpedance...

Here's a TIA circuit published in 2012, in RSI, by Yale physicist, Stephen Eckel. ?A high dynamic range, linear response transimpedance amplifier.? It's easy to implement, and super useful. The TIA has multiple ranges, each with its own output, but multiple ranges are active at once; there's no loss of data as would happen switching range resistors. Stephen and his co-authors ...

We need a 25kV rms AC signal. OK, that's 70kV p-p. I had a 30kV Trek model 678 amplifier, a huge beast procured on eBay, but I fear it...

We need a 25kV rms AC signal. OK, that's 70kV p-p. I had a 30kV Trek model 678 amplifier, a huge beast procured on eBay, but I fear it was thrown away in a downsizing move, damn! With that we could make a 10kV rms AC signal, at a frequency of our choice. And maybe transform it up to 25kV. Years ago I made RIS-333 / RIS-470, a 10kV 600kHz amplifier / resonant-transformer for ...

I'm building a optical comm. circuit using an AD8015 transimpedance amplifier from Analog Devices....

I'm building a optical comm. circuit using an AD8015 transimpedance amplifier from Analog Devices. Datasheet: http://www.analog.com/UploadedFiles/Data_Sheets/AD8015.pdf Here is the circuit I'm using: http://gallamine.com/photodiode_tia_schematic.pdf I'm having trouble with the circuit producing a strong ~1.9MHz oscillation. This is independent of what the circuit is hooked to. I have trie...