# Search results

1. ### What is the voltage across this capacitor, inductor and resistor?

I can solve for the questions in completely series or parallel circuits however having the capacitor and inductor in parallel while the resistor stays in series is stumping me completely.
2. ### Magnetic field put off by high current (causing cross-talk between wires)

Ok so I haven't been on here for a while but I can't seem to find an answer to my question anywhere and really need some help! So I not only am an electronics hobbies but I have fun installing car audio systems as well. The problem I am running into is that I would like to run an alt wire...
3. ### MOSFET not working with digital input gate signal, Help please

Ok, so i have a picaxe microcontroller putting out a pwm signal to the gate of an irlb3034 "logic level" n-channel mosfet. The mosfet is for grounding on and off about 8v of 20 to 40 amps. When i take my circuit and jump 8v directly to the gate of my mosfet everything works perfectly...
4. ### ASK transmitters in parallel

I have built a remote control car, pwm speed controll and all, using picaxe microcontrollers and gained a lot of experience doing it. I used a low power i think 20mw transmitter you can find all over ebay that uses a 433hz carrier wave. A long time ago i found a 1w transmitter meant to be a step...
5. ### Equilizer with lm833

I am looking to design an equalizer using the lm833 op-amp. I have used the lm833 to make an active crossover and pre-amp but what i really need it to use one of the op-amps in each lm833 as a bandpass filter to make the different frequencies So that i can have 2 adjustable frequencies for each...
6. ### Sine wave into wattage

So my question is about calculating wattage with a sine wave. So with speakers I always just thought of it as the basic vi=w So a sine wave of 12v through 4 ohms will produce three amps and thus 36watts. But when you put a square wave and use pulse width modulation on something like an led or...

I have an old mosfet amplifier which I plan to upgrade, I have never done this before but I am very experienced in electronics and have built many amplifiers before, just not mosfet amps. I am not 100% sure how the n and p channel mosfets are biased or set up but one upgrade I want to do with...
8. ### Current fraction of a sinewave

So PWM can simulate a decrease in voltage when useing a stable amplitude. 10v50% duty cycle is 1/2 the amplitude meaning 5v. And if this is through a standard resistor then you will see 1/2 the current. But what about a sine wave? What fraction or percentage does this come out to be? What...
9. ### Damaged split supply amplifier

I have a boss subwoofer amplifier which I recently discovered was causeing the distortion I have been hearing in my car. this amplifier consists of a PWM powersupply turning the 13.5v from my on car to a +45 -45 power supply. Then there are 8 mosfet transistors, 4 in parralel powering one...
10. ### Combining modules to transmit video signal for RC car

I don't see why not but is there any reason that i could not use these modules http://www.ebay.com/itm/121370353437?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 to make a wireless link between this camera and screen...
11. ### How to transmit composite video

Can I use a 315MHz transmitter module to send a composite video signal to another reciever module?
12. ### Help -- car stereo is acting up with hand made amplifier

I am adding 2 extra rear speakers in my jeep, I have some rca cables comming from the rear speaker pre-amp outputs from the back of my pioneer stereo. My plan which works beutifully is a dc-dc boost module bringing the cars 12v up to 20 for the main amplifier. The main amp is a 2x25...
13. ### Single supply preamp and active crossover

Hi I am making a preamp and active crossover using the lm833n dual op-amp. I have already done a project similar to this one and both the preamp circuit and crossover circuit worked beutifuly, although that project used a split supply and for my car audio I need a single supply. I have...
14. ### Useing single supply amp with split supply preamp?

I just finished a preamp/active crossover using the lm833n but the amp I need to run it with is a class D single supply board. and so the ground on the board is just negative. Can I run my [high pass/ground/low pass] signal into this amp? they are sharing a 24v power supply though and if I...
15. ### Charger using mosfet not working, help please

Long story short, I have a circuit board with I programmed smart charger on it. The microcontroller is supposed to put out 5v to trigger an enhancement type n-channel mosfet which simply connects 15v to my battery. But only 3v is coming out of the mosfet. It is an irl510, what is going on?
16. ### Use 433MHz transmitter for video rca?

Hi I want to transmitt a video rca signal with dome of the 433mhz transmitter and receiver modules you can get on ebay for cheap. I have used them alot and have accomplished transmitting data through picaxe microcontrollers successfully. But could I use it to transmitt a video rca signal...
17. ### Simple understanding of mosfets

Ok so I am pretty experienced, I've done tons of analog and digital circuitry but mostly programing microcontrollers. But I never really got to understanding mosfets too well, so this is what I know, N-channel are turned on by posotive voltage p-channel are turned on by negative voltage...
18. ### How to use camera module?

http://m.ebay.com/itm/271230081889?cmd=VIDESC&gxo=true How can I set this module up to have just a single video output so it can work with rca?
19. ### Converting split supply amplifier to single supply

I am talking about those 5pin AB amplifiers like the tda2030 for example. You can power them with posotive and negative 12v, which is equal to a total 24v, Or you can modify the circuit for a single supply, but if you do that so you can use a single supply12v, is it equivalent in output...
20. ### Determining truth of 555 watt amplifier board

Determining truth of "555 watt" amplifier board My math is showing that this amplifier is not 555watts but 140watts at 8 ohm at +-36v and 555 watts when shorting the output with ground. What do you guys think? amplifier board...
21. ### What safety precautions can I use for an amplifier?

I do alot of electronics and have built high power amps at home, im making one for my dad and I am putting the outputs on delayed relays so you do not hear the pop when the amp turns on and off, but I just remembered that there are other instances which will turn off the relay for safety, as...
22. ### Audio amplifier power supply question

So I had an old home receiver which broke down so i took out the large transformer 6800uf caps and rectifier. This receiver put out 60 watts out of each chip so from my many hours of being on google in the past, the chips should require +-35v, and because of the increase in voltage after...
23. ### Negative voltage regulator.

So for a power supply project I need a voltage regulator giving me a positive output at around 40v. Obsessively you can not buy these, So i am useing a circuit which consists of a resistor, npn transistor, and zener diode. the positive input goes to the collector of the transistor and through...
24. ### How can I cut out 60hz reception from transformer?

I just made an amp for a friend giving about 30 watts x2. but it is in a small project box and I am recieving 60hz coming into the input of the amps. I have done tests and it is the EM field of the transformer, I have 2 trimpots on the inputs to the amplifier and have been able to cut out this...
25. ### Easy Q about fuse placement in transormer-based power supply

Making an amp for a friend, useing a split supply with center tabbed transformer as ground for the chip, I think I heard the current alternates comeing from = and negative into ground, or from = and ground into negative or somthing, so where do I put the fuse?
26. ### Remote audio and video.

Hi I think this may be a dumb question but what the heck... So i have a very small remote camera with audio, the thing is the size of like 4 dice. But it doesn't have good range with the reciever, only like 30'. I do a lot of electronics and have made remote controll circuits useing...
27. ### Problem with voltage regulator

So I need to use this LM117t 3.3v voltage regulator and I asumed the pins were the same as most regulators where you have in/ground/ and out. But it is not working that way, does anyone know the in and outs of this regulator or have an alternative?
28. ### Amplifier supply current.

So I want to make a tda2050 amlifier with 4 of these chips, and after posting a lot of questions about different audio chips here, the chips always turn out to draw a few amps EACH as said in the datasheet. On this chip it says a max of 5 amps and people always tell me to supply them with a...
29. ### Learning about logic gates

Hi I am learning about logic gates and am having some fun with them but somtimes in my designs I only have use for maybe 1 or 2 gates, this is not convenient sence the chips I use have 4 or 6 gates in one chip, does anyone know where I can find NAND, AND, and inverter gates in 8pin dip or less...
30. ### Bridge mode with amplifiers?

I read that bridge mode in amplifiers will, for example, take a 100 watt amplifier at 8ohms and turn it to a 200 watt amplifier at 4ohms. I was going to use 2 tda2050 amps, each running one speaker, but if I use 2 amps in bridge running 2 8ohm speakers in parallel, would this give me double...