Sziklai pair power amplifier bias

Started by bitrex in sci.electronics.design7 years ago 24 replies

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...


current amplifier or current to voltage op-amp

Started by Anonymous in sci.electronics.design9 years ago 49 replies

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...


Error Amplifier Design for SG3524

Started by Myauk in sci.electronics.design11 years ago 4 replies

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 ...


9-decade transimpedance amplifier

Started by Winfield Hill in sci.electronics.design3 years ago 33 replies

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 ...


25kV AC

Started by Winfield Hill in sci.electronics.design3 years ago 72 replies

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 ...


AD8015 - transimpedance amplifier oscillating

Started by Anonymous in sci.electronics.design15 years ago 6 replies

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...


Need schematic for a 100 megawatt audio amplifier

Started by Anonymous in sci.electronics.design4 years ago 77 replies

Need schematic for a 100 megawatt audio amplifier using vacuum tubes.

Need schematic for a 100 megawatt audio amplifier using vacuum tubes.


Question regarding class F amplifier efficiency

Started by amal banerjee in sci.electronics.design3 years ago

Could some electronics guru here please provide some hints. I am SPICE simulating a class F amplifier with 3, 5 and 7 harmonic tuning and an...

Could some electronics guru here please provide some hints. I am SPICE simulating a class F amplifier with 3, 5 and 7 harmonic tuning and an operating frequency of 500 MHz. I am using VFR92A as the transistor and measuring efficiency. The RMS output power is computed as : RMS output voltage x RMS output current across a resistor. The input DC power is measured as: RMS input DC current x...


Old school Push pull audio amplifier transformer flux managment

Started by mike daniels in sci.electronics.design12 months ago 13 replies

I have a switched mode power supply background and an looking at something like this for an old school audio amp...

I have a switched mode power supply background and an looking at something like this for an old school audio amp design. https://www.circuitstoday.com/push-pull-amplifier For SMPS pushpull we always used current mode control to assure the flux in the core does not walk all the way into saturation. Looking at these designs, none monitor or measure the current to assure the flux


RF power amplifier for Nuclear Quadrupole Resonance (NQR) spectrometer

Started by BioPhysics2016 in sci.electronics.design6 years ago 13 replies

Hello, I'm building Nuclear Quadrupole Resonance (NQR)to test for 14N. using the SpinCore Radio processor USB board. Here is the manual of the...

Hello, I'm building Nuclear Quadrupole Resonance (NQR)to test for 14N. using the SpinCore Radio processor USB board. Here is the manual of the board. http://www.spincore.com/CD/RadioProcessor/RadioProcessor_manual.pdf I could not find low-cost 50/100/200 Watts RF power amplifiers(0.25 - 10 MHz). I have just found the following RF power amplifiers: 1- ENI 325LA RF Power Amplifier, 250...


EG&G 113P Amplifier

Started by Anonymous in sci.electronics.design5 years ago 5 replies

Hi, anyone interested in a EG&G 113P Pre-amp? I never used it much and just verified it works at 10X gain. Please message and let me know. ...

Hi, anyone interested in a EG&G 113P Pre-amp? I never used it much and just verified it works at 10X gain. Please message and let me know. Asking $325. http://i64.tinypic.com/2e21e1k.jpg Thanks, Scot


Nanoamp calibrator again

Started by Phil Hobbs in sci.electronics.design10 years ago 49 replies

So, I had a chance to get back to that calibration gizmo for my biochip front end amplifier (1 nA at the shot noise limit in a 100-MHz BW). It...

So, I had a chance to get back to that calibration gizmo for my biochip front end amplifier (1 nA at the shot noise limit in a 100-MHz BW). It turns out that it's possible to do a very nice job, assuming that the integration cap (C1 in the schematic) has zero inductance, but as much as 0.05 nH blows it out of the water. (Should have thought of that, of course, but oh well.) Try running ...


low cost isolation amplifier

Started by Anonymous in sci.electronics.design1 year ago 25 replies

https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3 D -- Father Brown's figure remained...

https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3 D -- Father Brown's figure remained quite dark and still; but in that instant he had lost his head. His head was always most valuable when he had lost it.


Amplifer Design

Started by Cursitor Doom in sci.electronics.design3 years ago 64 replies

Greetings, gentlemen, This is the schematic of the CRO x-amplifier I've been investigating lately. It's supposed to provide sufficient...

Greetings, gentlemen, This is the schematic of the CRO x-amplifier I've been investigating lately. It's supposed to provide sufficient potential difference to the x plates in the tube so as to sweep the electron beam left to right in accordance with the timebase setting: https://yandex.com/collections/card/5da36a58f05bf23ffde0742e/ At first I thought this was operating as some kind ...


How to select shunt capacitor for class E amplifier

Started by amal banerjee in sci.electronics.design3 years ago

Could some electronics guru please help ? I am trying to do some SPICE simulations for class E amplifiers. How is the shunt capacitor value...

Could some electronics guru please help ? I am trying to do some SPICE simulations for class E amplifiers. How is the shunt capacitor value calculated ? Any hints, suggestions would be helpful. Thanks in advance.


Whats Wrong with the DC300A answer

Started by Phil Allison in sci.electronics.design3 years ago 4 replies

Hi to all the terminally puzzled, --------------------------------- THE *problem* with the Crown DC300A is simple, but virtually unknown...

Hi to all the terminally puzzled, --------------------------------- THE *problem* with the Crown DC300A is simple, but virtually unknown in the industry. Any amplifier that has response to DC is similarly questionable as being suitable or safe to use driving loudspeakers or transformers. Such amplifiers produce a large DC component when driven into clipping with an un


MPPC amplifier

Started by Fitzgerald in sci.electronics.design5 years ago 5 replies

I'm looking into low-light detection using MPPC's and I am testing using the Hamamatsu C12332-01 evaluation module. I am looking for general...

I'm looking into low-light detection using MPPC's and I am testing using the Hamamatsu C12332-01 evaluation module. I am looking for general hints, tips and tricks to maximize the performance of these modules. We'd like to have a measure for the total amount of photons collected every 20-100ns (exact timing t.b.d.) One of the things that surprised me was that the frontend of the eval...


amplifiers will, oscillators won't

Started by Gerhard Hoffmann in sci.electronics.design3 years ago 6 replies

I still have a skeleton in the cupboard and the current lock down seems fine to bury it for good. Let there be an amplifier consisting of...

I still have a skeleton in the cupboard and the current lock down seems fine to bury it for good. Let there be an amplifier consisting of one or more CS input JFETs, an optional cascode, an op amp for plenty loop gain and feedback into the source. Everybody and his dog does this, but it has a drawback: it is not stable. If you measure into the input, you see a capacitance in series wit...


Paper on reducing 1/f noise in amplifiers

Started by Phil Hobbs in sci.electronics.design8 years ago 16 replies

AoE 3 P. 485 (footnote 22) references a paper by Broderson, Chenette & Jaeger, entitled "A Superior Low Noise Amplifier", 1970 ISSC, P. 164....

AoE 3 P. 485 (footnote 22) references a paper by Broderson, Chenette & Jaeger, entitled "A Superior Low Noise Amplifier", 1970 ISSC, P. 164. Before I feed yet another $31 into the voracious maw of the IEEE, does anybody have a copy handy? Thanks Phil Hobbs


Educated Guess (audio levels)

Started by Cursitor Doom in sci.electronics.design2 years ago 4 replies

Gentlemen, Say I hook a dynamic mic up to a voltage amplifier of 1M+ Zin. The amp provides a gain of around 650. Could I reasonably expect to...

Gentlemen, Say I hook a dynamic mic up to a voltage amplifier of 1M+ Zin. The amp provides a gain of around 650. Could I reasonably expect to hear some (albeit very low level) output if I tap the mic with my finger whilst listening for an output signal with xtal earpiece? Thanks.