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  3. Hi all,ive built this but have issues with current regulation,ive added another led as well fed frompin 6 of u3,its a dual colour led,fed fromq3 its red indicating cc and from u3 pin 6 its green indicating cv,when i load the output and turn my current pot ccw untill the led turns red,ie cc,i can still increase the voltage using p1,im using MC34071AP opamps,d9 is fitted good and works,any ideas?,also when in cc mode if i wind p2 ccw(its a 10k 10 turn pot,about 1/4 turn from the end the voltage suddenly jumps up by about 3 volts,thanks in advance.
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  5. This is MicroPython project developed using Ameba RTL8722. MicroPython is offically supported on Ameba RTL8722, so through this demo video, we will see how easy and fast it is to develop a simple server socket on Ameba, which would then control other peripheral to perform other tasks. Here we are using a client socket code running on PC to send a 'Hello, world' string via the WiFi network, Ameba receives it and if it is indeed 'Hello, world' then it will blink the LED. Check out the demo video down below, https://youtu.be/pEMkwvw-r18 Code used: #!/usr/bin/e
  6. well i found d7 shorted,that fixed the u2 getting hot+low output issue,only trouble is now is with the current regulation,its like all or nothing,when it goes into cc mode,if i wind the volt pot ccw the led stays lit,funny tho as it still lets me turn the voltage up when in indicated cc mode,r18 is 33k.
  7. There are others who are more qualified than I on this circuit but not letting ignorance stand in my way I will continue anyway. In the various schematics U2 is connected to a transistor base through a 0, 22, or 1k ohm resistor. So it makes a difference which schematics you are referring to. At 1k the current from Q2 would be limited to 33v/1k or 33ma well within the 88ma max. of U2. Else for the 0 or 22 ohms I would wonder about diode D10 if it is shorted or not.
  8. ive built this psu,when q1 is connected u2 gets hot+ output drops to 0,if i cut the emitter of q1 it seems to work ok,any ideas,btw in cc mode i get a spike on switch off,in cv mode its fine,cheers in advance.
  9. Account details sent. During the test process, keep this in mind: the better the photo, the better the inspection results. We gave you full access to all the features of the service. Any inspection will take approx 1-3 seconds. Let us know how it went 🙂
  10. Looks very interesting. I have a small PCBa company in the States. Assembling about 2000 board / month and an inspection service like this will really help me out. I just emailed your asking for the TEST account credentials. Thanks for the post.
  11. Hi all, We have developed a neural network tool capable of detecting faults on the electronics components placed on a PCB just from a photo. The service details can be found here: www.AgnosPCB.com Please feel free to take a look at our site and the current visual inspection tool: the web App https://app.agnospcb.com/ (You just need to drag and drop the photos you have taken to your PCBa) This neural network powered inspection tool can detect missing/misplaced or rotated elements on any PCBA. It does not matter the type of elements placed/ PCB architecture/ color or size of
  12. It is essential to get assignment help from reputable organizations. This ensures the quality of the work is observed and that all instructions are followed.
  13. It is essential to get assignment help from reputable organizations. This ensures the quality of the work is observed and that all instructions are followed.
  14. FM transmitters/receivers are among the top favorite circuits of any electronic enthusiast. In this article/video, I have introduced a complete digital FM receiver design that has equipped with an LCD screen and three push-buttons. It can search for the FM signals from 76MHz to 108MHz manually and automatically (Scan mode). The signal strength is also displayed as a bar graph on the LCD screen. The output sound is amplified by a 3W+3W Class-D stereo amplifier that handles high-quality and strong enough audio power. As a controller, I have used the cheap and popular Arduino-Nano board. So let’s
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  16. At 3 seconds pulsing you could see that with a multimeter. I would start at the output of U2 looking for pulses; if so look at its input and likewise back to U1 and U2 outputs and inputs. The op amps U1 - U3 (TL081) are short circuit protected. "When shutdown occurs and less power is dissipated, the circuit cools as desired. The shutdown circuit is then disengaged and the circuit heats up. Again shutdown occurs and so forth."
  17. heres a better schematic i hope,the first is the same as mine,my rv1 is 5k,2nd schem is origina,also i still have q1 in my version,should i remove it?,cheers m3vuvl. heres a better original version
  18. Hi Paul Check your VRef circuit around U1, it seems very suspicious to me. To which Vref voltage you are designing for ? I would replace this small circuit altogether.. seems like a mistake in the schematics there. Best of Luck Guy ePiccolo Engineering
  19. Do you have a better schematic? It's hard to read this one. Can you reference where you got the schematic or the kit?
  20. ive built this psu as per the schematic,the issues i have are,the output is 30v with the voltage pot fully ccw,if i turn the current piot almost fully ccw the output drops to 0 with the led on,if i turn the current slightly cw it oscillates from 0v to 30v about every 3 seconds,the led flashes in time with this also,im using mc34071 opamps ,the only thing i havent changed is d7,its stil the 5.1v zenner,q2 is a bd137 and im using 4x 2n3055 pass transistors with 0.1r emitter resistors,any ideas on whats causing this wierd behaviour?,cheers m3vuv.
  21. Thanks for the informative topic, I'm just studying this, also for I recommend a useful resource that will help save time, especially for students, go to https://edusson.com/ and check out the services of this service, Edusson will help you write your essay from initial topic to finished paper, there is information about the best performers, their ratings, functions and their profiles, go now, this will help you get high-quality work in a quick time frame.
  22. Q: Can the module amplify square wave or pulse? What is the module bandwidth? A: The module can amplify low-frequency square waves or pulses. Because it is an audio amplifier, the total bandwidth is not high. Signals within 100K can be amplified. The module is compatible with DC input. This is the over priced one with best Q/A https://www.amazon.com/operational-amplifier-current-continuous-voltage/dp/B07D8V1YBG/ref=sr_1_18?dchild=1&keywords=opa548&link_code=qs&qid=1605968887&sourceid=Mozilla-search&sr=8-18&tag=mozilla-20 The best price is 57.80$ Amaz
  23. MetaTrader 4 is an excellent device for trading on Foreign exchange markets. As an ARM-based tool customer, I would actually wish to attempt to mount MetaTrader 4. But for now I need to attend Trading Education & Lectures from AstroTrading.co to learn more.
  24. The OPA548 op amp looks promising. It has up to 5 amperes output into 4 ohms or better. It can be bought in a complete amplifier see OPA348 on Ebay or Amazon.com just search for OPA548. The data sheet is here: https://www.ti.com/lit/ds/symlink/opa548.pdf As the amp can be used in a dc pwoer supply makes it look useful. If you have an Amazon account you can ask about the complete amplifier low frequency range else I can.
  25. Python has become the most popular language in the past few years, and now we can even program Microcontrollers with Python language through a project named MicroPython. MicroPython is, by its definition, a efficient and lean python compiler and runtime that is designed for Microcontroller. It supports Python 3 syntax and can be run interactively using its command prompt--REPL. Now, MicroPython has even been ported to Ameba RTL8722 dual-band WiFi and BLE 5.0 microntroller, here is a demo of how it works, Demo Video
  26. Tone generator circuit using 555 timer Bird sound generator, Ambulance Siren Generator These are some circuit diagrams of the sound generators. Sounds are like Bird sound, Ambulance siren, Beep Horn, and other different types. Use 9 to 12v Dc supply and components value should be the same as suggested in the diagram because any variation of components value can change the sound type. By some changes of values of some components as given below in the diagram, you can produce many different type of sounds. Use a medium-size speaker, These circuits can be useful for the making of Ala
  27. why ac current passes through capacitor but dc can’t how capacitor block dc current Explanation 1 We try to understand using a discharged battery in the circuit. When switch on, the battery is starting to charge and increasing the voltage level of the battery and there is a flow of current. When the battery gets fully charged and the voltage of a battery increase and is equal to supply voltage then there is no flow any current between them. Let us consider a simple circuit as given below. In this circuit, a capacitor is connected with a resistor in series. A 12v DC
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