Can i bridge two bridged amplifiers?

Well, the question itself tells a lot (mostly how bad it's asked). I have a quad amplifier that i'm using as a stereo bridge. So is there a possibility to bridge those two (or parallel em?)   This amplifier is not some factory made amp, It's a simple amp i made with TDA7375. The output is somewhere between 2x30 and 2x40W , but i'm only using one channel and it seems like a waste (I'm using it as a small woofer driver, didn't have another amp so this one had to do) So, The question is Is there a way i can make this Mono so i can get some more power out of it (or just use both channels so i don't only use one). The amp is TDA7375 and the speaker is Novex sps250i (yeah, it's crappy but sounds decent) Also it says nowhere that this one can be bridged to mono. Also won't it work if i parallel two channels and then bridge them to mono? (as in parallel four into two then bridge those) From what someone told me if i want to parallel it i'll need some 0.1ohm 5W resistors (those are really cheap and easy to find here) Thanks in advance.

Question by T0C   |  last reply


Diodes for Bridge Rectifier?

 Please Help! I need to make a bridge rectifier for a shake charging flashlight which also include using a 5V regulator - so it won't be a very high voltage, if that matters.  What type of diodes do I need for this bridge rectifier?  HELP!  thank you! patti :)

Question by mckywer   |  last reply


Transistor H-bridges

Is it possible to make a transistor H-bridge with PNP transistors or can it only be done with NPN transistors.  As far as my knowledge( or lack thereof) of transistors goes, I think it would be possible, but it would require more than 4 transistors and it would be much more complex, however I could be entirely wrong.  Any input would be helpful, thanks.

Question by jpenn   |  last reply


bridging my connections

I need help bridging my connections. everytime i try it says i must select two LAN connections that are not using internet connected sharing. i have looked all over and am pretty sure its all off, it wont let memerge the two together by highlighting them either it just moves the connection order around please please help. thank yoou!!!?

Question by RECONWARRIOR   |  last reply


Cordless Telephone Bridge

I'm trying to figure out how (or if) I can use an old cordless phone as a tranciever, wiring in an rj11 jack to the phone's reciever to essentially make a cordless phone "bridge" so that I can use my desk phone in an area without phone cabling by plugging it into the cordless phone's reciever. I've tried the phone over power adapters and haven't had great luck with 'em, so I'm trying to think outside the box. Anyone have a suggestion or two?

Topic by ptilton 


How to make a strong bridge by using

How to make a strong bridge by using 15 straws , 35 paddle pop sticks , 3 sheets of cardboard, 50cm of sticky tape, wood glue? my bridge have to be 25cm long and 14cm wide. Thank you for helping

Question by bryan1234567890   |  last reply



How to construct a Bascule bridge using only popsicle sticks, glue and cotton strings?

How can we construct the truss structure and the hinges, mainly the hinges, using only the sticks, thin (1 mm cross section) cotton strings and glue? can u please suggest ideas for the design of the same?? We would also appreciate if you'd give us suggestions for the construction of the open-close mechanism, which incidentally, what a Bascule Bridge is all about!

Question by fear_black_death   |  last reply


Using the IRS2110 for 36v H-bridge? Answered

So i have some 850W 36v DC motors that i need to design an H-bridge for, and ive decided to use the IRS2110 to driveing them, since i need to drive the highside fets. I however have no idea of how to use that chip. Any help? :P

Question by dumle29   |  last reply


do any one know how to make a salt-bridge in mfc?

Do any one know how to make a salt-bridge in mfc? please give some suggetion

Question by mohit_leo   |  last reply



if i want to rectify 12v AC to 12v DC how much values of diodes i'll use and how can i calculate it(i.e diode 1N4007)?

Like we mostly used (4 x 1N4007) Rectifier bridge to convert 12v AC to 12v DC.why and how we can calculate it?Formula?

Question by AliR79   |  last reply


Are all rectifiers bridge rectifiers?

Do all bridge rectifiers have 2 inputs for ac and two outputs for dc.  I see some components called "rectifiers" which have three pins.  Does  this item change ac to dc?

Question by Noblenutria   |  last reply


What bridge design is best? Answered

I need to design a bridge for a project but it has to be made out of MDF that is 20cm x 33cm x 3mm MDF that is 3mm x 3mm x anything hot glue and string. It has to be strong, span 60cm have a 30cm clearance and be 20cm wide. It can have no supports and not attach to the ground. The wide MDF can only be used for the road and you cannot layer it.

Question by eggyeggyeggy   |  last reply


Are bridge rectifiers "downward compatible"? Answered

If I have a power supply circuit that requires a 25.4VAC, 2A transformer connecting to a bridge rectifier, could I use a rectifier that is rated at 50V, 4A, or do I need to get one that matches the input more closely?

Question by Xombee   |  last reply


H-Bridge Circuit Help

Hello,I have an assignment to build an H-bridge circuit to control the direction of a motor with two buttons. The only materials I can use are depicted in the image; only three resistors, a battery pack, two button switches and an L283D chip. Based on the template given to me, I constructed the circuit as shown in the picture but it does not work. It looks very messy and I'm sure there's an easier way, but I just want to get it working first. If anyone knows what I'm doing wrong here I'd appreciate it.

Question by GaleDale   |  last reply


SMPS H-Bridge trouble

Hi,  I've built a 1kW SMPS designed to take a 350V unsmoothed DC input and convert it to 3kV @ 300mA. The circuit is basically Uzzors2k's design seen here minus the overcurrent protection and smoothing capacitor (for now), however I accidentally wired the GDT outputs backwards so the gate resistors (33ohm 2W) are on the source. I have used alternate MOSFETs the latest attempt with FDPF16N50T's. I've had various problems with the circuit, primarily the MOSFET's exploding seemingly from overvoltage (evidence of flashover in some cases despite no evidence of secondary leakage (i dismantled the transformer to check)). During my last test I had a flashover between the drain and source pins of one of the FET's, in addition all of the gate resistors were smoking hot after, seems the gates had all been shorted (first time this happened, other occurrences were from case to ground). This happened despite the variac only being turned up to 40% which should be well well below the pin spacings maximum voltage tolerance. I have checked the drive signals, they are quite nice square waves at about +-15V with some oscillation on their rise. I have built SMPS's before, one is currently working with similar MOSFETs using a half bridge at 300W. Does anyone have any suggestions as to why these troubles are occurring or have any suggestions to fix it or have any alternative circuits that may be less troublesome (is a h-bridge easier to manage?)? Thanks, Stephen I​ just gave it another test with a H-bridge instead and the source of one of the FET's blew so it appears that there is just FET failure and maybe not arcing between drain and source.

Question by The MadScientist   |  last reply


Does anyone know if an IO-bridge module is a microcontroller, or just a bridge to the internet?

Would you need an additional microcontroller, such as an arduino, or could you control servos and lights directly from the IO-Bridge module?

Question by Bostonians   |  last reply


how to control a dc motor from a cd-rom with an h-bridge RX-2B ?

Hi,, i'm new here and i'm new using arduino,,,  i have an arduino uno, and i have to make a project for a class in my university.i would like to know how to use a dc motor form a cd-rom, i have an h.bridge RX-2B, and i need to know how to control the direction of the motor with those components, i've found some information around, but using another h-bridge, so i'm not sure about the configuration of my circuit, i jus t need tha for the moment,,,  thanks?

Question by edwin0791   |  last reply


Can I replace MOSFET with IGBT in Solid State Tesla Coil?

I have a half-bridge circuit. It using IRFP460. But I want turn this driver to high power version. So I request some help! Can I use IGBT for half-bridge circuit?

Question by james34602   |  last reply


How can I speakers in such a way that i get the best outcome in terms of power?

Ok i have 4 speaker which can handle 80W continuous power and having an impedence of 4 ohm each. I also have a 4 channel amplifier. The amplifier outputs are as follow: 60W RMS x 4 @ 4 ohms  80W RMS x 4 @ 2 ohms 160W RMS x 2 @ 4 ohms bridged How can i wire the speakers in such a way that i get the best outcome in terms of power? I've been thinking of wiring 2  sets of 2 speakers in parallel  and connecting them to the amp as bridge stereo. But the problem is that i don't know if it will cause problem to the amp. because the amp is 2ohm stable but i don't know if it is 2ohm stable when bridged 

Question by ARJOON   |  last reply


Odd Breadboard Question

Hi All  I am brand new to hobby electronics and would love one day to be able to create the endless amount of cool Instructables but I have ran into a problem on my first attempt at putting theory into practice and would really appreciate any help. I have made two diagrams / images showing the circuit I made I have attached them to this post. I am using an Arduino Uno as a power source.... I ran a 5v positive from the 5v pin on the Arduino using solid core jumper to the top of the breadboard onto the positive row / rail and a negative / ground jumper to the bottom of the breadboard. In the middle of the breadboard I placed a 1k ohms resistor bridging the gap / grove/ divide and ran the positive feed through it and on to the anode leg of the LED. The cathode leg of the LED was connected to the negative row / rail completing the circuit. All works as it should because of the high resistance from the resistor the LED barely lights and is green as it should be. So without using a multimeter I know and can see the resistor is clearly working. However if I move the resistor so it's still on the same line / row as it was but no longer bridging the gap the LED goes super bright and turns yellow which means that the resistor is no longer working which I can't figure out why because I know there is definitely current flowing through it given the extreme reaction of the LED. I vaguely remember reading somewhere on these forums that Fritzing is not liked very much so I hope no one minds but to help explain what I mean above I have created two diagrams / pictures using Fritzing. The images diagrams shows the resistor "bridging" and working and the other shows it not bridging and therefore not working. So my question would be why given the resistor has current flowing through it does it not work unless it's bridging this middle divide / gap / grove? It makes me think I am missing something really stupid that everyone should know about breadboards but just seems really odd to me. Many Thanks Rab

Topic by belfastrab   |  last reply


l293d ,problem wth the output current?

Hey people , i have build a line follower robot using -(arduino,motor controller(l293d), IR modules and sensors) WELL NOW I HAVE GOT A NEW METALLIC CHASSIS(its kinda heavy).Earlier we use a cardboard box and it worked just fine . But now the motor driver is not able to give enough current to drive the cart.But when i connected it without the motor driver its able to drive the cart forward. So my conclusion is that the IC (l293d) is the cause of my problems,so i want to know how i might be able to fix it OR if  i have to use another ic like (SN754410 H-Bridge)

Question by cthaliyath   |  last reply


How do I get my PS3 to pick up more/better wifi internet OR have it pick up my desktops internet? Internet is from moms.

How do I get my playstation PS3 to pick up my desktop internet, that I get via my moms place down the street? I get my desktop internet connection via a engenius bridge and large antenna from my moms place down the street. I just got a PS3 and the built in wifi thats built in cant pick it up the signal cause her place is too far away. Is there a way that I can get the PS3 to pick up a signal from my desktop, even though my desktop internet comes from someone else??

Question by krose1223 


how to measure inductance using a bridge?

My LCR meter can only read inductances of mH to a few Henries. I need to make a 470uH inductor, since in my place inductors are not so common. How can i measure inductances at microhenries if my LCR meter's reading capability only ranges from millihenries to henries? Someone told me to use bridges like wheatstone bridge or maxwell bridge to have an accurate reading, but i don't know how to do it. Can you suggest any reference? I prefer doing wheatstone. Thank you in advance :)

Question by codestroy7   |  last reply


Need urgent help in H-bridge!! Answered

Hi,      I am building a H-bridge to drive my robot's motors. I am using the circuit from the following link http://wiki.mech.uwa.edu.au/index.php/Micro_crash_course/pwm#P-channel_FET     (Figure 12). For the mosfets I have used IRF540 and IRF9540. The moment I connect this circuit to my 12v power supply, the IRF9540, heats up very quickly although I have not connected it to any load !  For logic input, I am using the Arduino. Please help me with this H-Bridge circuit. Thanks in advance.

Question by Jayvis Vineet Gonsalves   |  last reply


Use internet while bridged connections?

I did the instructable for using your laptop as a wireless access point for your xbox 360. I got live to work but now when I have the connections bridged I can't use the internet on my laptop at the same time. Is there any way I can use my wireless internet on my laptop while having the connections bridged?

Question by ovk2k5   |  last reply


Wein-Bridge Oscillator help needed

I've been searching google for about an hour now, and I need help with making a Wein-Bridge Oscillator. What I need help on:- Can I use any op-amp? I want to just go buy one at radioshack (don't feel like paying 7 bucks for a tiny IC online)- What kind of incandescent bulb should I use/is there a more modern substitute?solved by killerjackalope- Is there a way of controlling the frequency with only 1 potentiometer (I found this website but I still have the same questions as above and I don't know if it'll apply).-how much power does it consume assuming there's only a light load on the output?

Topic by guyfrom7up   |  last reply


I have some questions on bridge rectifiers and how they work/output current and voltage, see details for full info.

If I use a bridge rectifier to convert AC 110V into "DC" 110(154V), I'm guessing the amperage rating on the rectifier is how much current will be available to use vs the voltage being output as well? The reason I put 154 volts is because peak voltage is 110ac times 1.4. I'm using this for LEDs, just to provide some more info. The bridge rectifiers I have are rated at 200V and 1.5A.?

Question by opliko   |  last reply


BRIDGE RECTIFIER ? used electronic transformers 240AC in, 65va max - 12AC out,, to power LED strip lights?

Hi, I need help to understand what I would need to use a bunch of these (free) old transformers to power various 12vdc LED strip lights in my garage.          I have read-up on the subject of using a bridge rectifier in each circuit to convert the AC to DC,,, BUT,, being completely useless at formula / algebra / maths, I cannot work out which bridge rectifier would work for me. I can adjust the length of LED strip to suit, but the longer - the better!  The LED strips I have are 5m long, 300leds, & the specs say 5amp for the full length. So, is there a bridge rectifier available to buy, what number is it? (same if I need anything else)  Please help,, and try not to baffle me with techy science.  Many thanks.

Question by bowtie262   |  last reply


what is the best microcontroller to use ( pic ?) if i want to drive a motor forward and reverse using a h-bridge ?

Im trying to save space in the design and be cost effective( i wanted the pic and h-bridge and the motor to be under 1 inch) . so im trying to use the smallest chips that will do the job.  i was wondering if an 8-bit pic would do the job ?   edit: Id prefer using Microchips PIC, i think i have somewhat an idea of using MPLAB. Im planning on using a brushed DC motor, H-bridge, and Voltage regulator.  It has to fit under a 1' area taking up the least possible space because im using it as an unlocking/locking device. i was wondering what would be the best microchip pic that could achieve this with the least cost and size.

Question by dudeitskumar   |  last reply


I have a large bipolar stepper motor. What's the simplest circuit to drive it with a microcontroller (arduino)?

I have a large stepper motor with 4 wires (bipolar) from an old printer and I assume it's 12 volts, or at least higher than 5v. I have plenty of transistors: 2n3904, 2n2222, 2n4401 and 2n3906 (PNP). How do I drive the stepper with output from an arduino? (simple H-bridge schematic?) Also, how can i find how many steps it has? Thanks!

Question by Vick Jr   |  last reply


Enforcing polarity with an AC adapter?

Several months ago, I posted an I'ble for adding an AC adapter to something. The adapter I chose, from Radio Shack, is actually a two-piece "kit" -- the wall wart cord ends in a generic two-pin female jack, and they sell a bunch of different end plugs. The jack is symmetric, so that the end plug can be put on with either ground or hot on the outside.I've just realized that this could be a problem. If the electronic device expects red to be positive and black negative, then putting the jack on backwards would be equivalent to installing all the batteries the wrong-way about. Not a great feature.To "protect" the device, I'm considering adding a diode bridge to ensure that the internal "red wire" always carries the positive, and the "black wire" is always ground. Do more experienced folks consider this a good idea? Is it necessary? Would it be better, perhaps, to just epoxy the end plug so it can't be reversed?

Topic by kelseymh   |  last reply


How do I bridge two lm386 OP Amp ICs ?

My idea is to make a electret microphone amplifier powerful enough to drive a speaker. I was using the lm386 because I was familiar with it´s chracteristics and already had a schematic to make a 200 gain amplifier. However, when I tried to use this one to amplify a microphone signal it ended up not providing enough power to drive a 8 ohm speaker (you had to stand right next to the speaker in order to hear something and even when doing so the microphone seemed to only pick up loud noises) despite the results of a similar test made with headphones proved to be more than successful. Seeing this, I assumed that connecting another lm386 amplifier to the output of the first one would improve the results. Boy i was wrong. After hearing the unearthly noises that came out of my proyect I decided to do some research on the internet and came up with the bridge and parallel configurations. Nevertheless, i did not find any proper schematics involving two lm386. It would be of great help if anyone could hand in a  schematic or tip on how could I continue from ths point.

Question by MrB12   |  last reply



Shift Mosfet and H-Bridge for Arduino Question?

Hi guys, Im Rinozen.. Im newbie on Arduino and Electronic ^_^ Anyway, can you guys please help me? Look at the schematics i've uploaded. Are there something wrong about the track? And what value for the Resistors and Capacitors for the right choice? Sorry about my english ^_^ Thanks for reply... :)

Question by rinozen   |  last reply


H-Bridge Minimum Voltage That Can Be Switched

I am making a circuit that can switch the polarity of the output of my voltage supply at the timed intervals using a microcontroller. I am using a circuit similar to the one at this link: http://www.robotroom.com/BipolarHBridge.html. It works, but not at when the power supply outputs below about 3 volts.  Is there any way I can modify this circuit so that it switches the polarity all the way down to 0 volts?

Question by Ethanal   |  last reply


controlling coil using H-bridge...possible? Answered

Hi! Yesterday I bought a Nikko X-pander r/c car, for only $ 3, and I want to put my own electronics on it. I've seen that the front wheels are controlled by some sort of electromagnet that changes polarity to turn the wheels left or right. I already made my own homemade L298 module and I want to know if it's possible to use one channel of L298 driver to change the angle of the front wheels. Thanks.

Question by Timofte Andrei   |  last reply


where would i conect a capacitor on a bridge diode to get the best current smoothing? Answered

using a small homemade bridge diode to power some radio equipment. i want to try and "clean up" the dirty dc that it puts out. where would i put a capacitor and what kind/rating would i use? the AC supply is a lionel 18 volt, 80 watt train transformer, that i am going to callibrate to the 13.8 volts that my radio rigs crave. any tips/pointers/ suggestions?

Question by KJ4ZVQ   |  last reply


How to make a high amp bridge rectifier?

I want to drive a peltier plate from a 12v transformer coupled with a bridge rectifier , but the diodes get very hot , so how can I make a high amp bridge rectifier that can provide upto 10 amps?

Question by ssahoo1   |  last reply


are alternators AC motors with bridge rectifiers and/or diodes? Answered

I've got these two motors that run on direct AC (120 V). I want to generate electricity with them. Will they produce AC electricity that i can then feed through a bridge rectifier? Could you explain how an alternator generates electricity?

Question by cdubnbird   |  last reply


can bridge rectifiers be combined to double the amps? Answered

Say we have 3 amp 3 rectifiers soldered would that function as 9amp rectifier or needed to be wired in a special way, series, paralel with other components? I am building an unknown power wind gen ans I gave 10   3 amp rectifiers. Thanks for sharing.. Al

Question by celalboz   |  last reply


how to bridge two wireless routers with ethernet.

Https://www.dropbox.com/s/k94u03kytdn1jkq/INTERNET%20BRIDGE.jpg?dl=0 I want to add a bridge or extend (not sure of the correct term) internet to my 1st floor. I dont want  the second router or extender to connect through wifi with the first or main router, can I connect the second router to the first with cat5? and how?

Topic by ebaltierrez   |  last reply


Ardiuno Ethernet W5100 ic solder bridged? Answered

Hi I got a Ethernet shield for my arduino I have ordered, but the problem is that the solder on the IC seems to have run and bridged the connections. I have some pictures taken with a lens I had laying around... This is what I found. Please can you help me decide weather I should take it back for a full refund?

Question by Daniel Deacon   |  last reply


Right Transistor for a apx. 50watt H-bridge? Answered

Currently i am trying to make an Arduino UNO R3 control a 50 Watt (12 volts @ 4 amps) motor with an H bridge and use the Pulse width modulation on the Arduino to control the transistors. However i don't know what would be the best choice for transistors? Also I am new to this so can some also explain how transistors are named?

Question by luig   |  last reply


How to set 2-wire into bridge mode? Answered

Hi everyone! I have a 2-wire 3800HGV-B wireless router from AT&T; that I need to set into bridging mode not DMZ.  I have a DD-WRT router that I just installed on my home network, and I also have a small server.  Before the DD-WRT router, I had the server on DMZ on the 2-wire, and after I setup the DD-WRT router, it made me put that into DMZ mode.  I tried connecting the server to the DD-WRT and putting that on the DD-WRT DMZ mode, but that doesn't work.  I've tried using port forwarding on both my 2-wire and DD-WRT routers to send specific ports to the server on a private IP address, but that isn't working either.  The best solution I can come up with is to put the 2-wire into bridging, and a friend of mine did it with another 2-wire router (not the same model... he tried to help me out and wasn't able to do it), so I think it's possible, but I've tried to do it with no luck. I have tried Google, but everything that comes up that claims to be bridging is just setting the router to DMZ. Any help or other suggestions would be appreciated!  Thanks!

Question by thegeekkid   |  last reply


rc car no longer accelerating?

Alright, so ive got this rc car, it runs off of a 7.2v battery pack and has variable speed and turning. it is not a hobby-grade car, but it is still something id like to hold onto. today, when i tried to drive it, i discovered it could not accelerate, forwards or reverse. it can steer fine, but trying to accelerate does nothing. ive ruled out the controller and the motor, which means the h-bridge and associated circuitry must be to blame. i tested the battery in another car of the same model (not mine), and all was well there. the h-bridge must be PWM controlled in order for there to be variable speed, so heres what im figuring: the motor is making a clicking noise when i pull the trigger on the remote, looking at the motor, it is turning very little and then stopping and then doing this again, at a fast rate. when it stops turning for that split seond it returns to the original position, because it has turned so little. i know the motor itself is fine, because i connected the battery straight to it and it spun up and turned the wheels. i have a feeling the issue lies within the PWM control. i cannot guarantee the receiver chip is fine but it seems kind of odd that it would be the part to fail; regardless i cannot find a datasheet using the numbers on the chip. if i were to try and look for an issue/failed part somewhere, where might you guys think i should start? there are a number of transistors on the board around the h-bridge, some capacitors, and a lot of resistors as well. i checked all the resistors inside the h-bridge and they are all the same value as the bands indicate, andthere are no corroded or cold solder joints. i plan to test the h-bridge on its own once i find a diagram i can reference to, that way if the h-bridge works i can rule it out and narrow the possibilities. if you need any more information please let me know.

Question by zack247   |  last reply


Building a car sound system?

I recently got my car and want to boost the sound system by upgrading some speakers and putting an amplifier, i have 2X 30W 4OHMS 1X 350W MAX, 80W nom.  4OHMS My car has a pioneer mp3/cd player  with 4 channels(4x 45W rms) I want to bridge an amplifier to connect the 350W speaker for the rear only and use 2 channels for  the 2 front speakers. my idea is using two channels of the car player for the front. i will have 2 channels free [(left and right)rear] i would connect it to the amplifier, then bridge the amp to connect the speaker. can anyone suggest me a cheap amp to buy and tell me if my idea is correct???

Question by ARJOON   |  last reply


help upgrading an old RC truck?

Ive got an old New Bright RC truck, i got it around 2000 so as you can assume the batteries arent very good anymore. im not looking to repair the batteries though, im looking to upgrade the truck with a little bit of some newer technologies. heres where i ask for help: i dont want to overpower the control board in the car, since it may have adverse effects on how it performs, so i just want to up the power to the motor. i have some D2583 and B1658 transistors, i found a datasheet for the D2583's that says they are high power NPN transistors, but no such luck with the B1658's. using the D2583's (i have 6 of them), i want to create a circuit that runs from the main board, and acts as a second H-Bridge (or some sort of control circuit) that controls more power, so i can safely run more voltage to the drive motor without overpowering the main circuit board. does anybody know how i can do this? i have attached a picture of the area on the circuit board where the original H-bridge is.

Question by zack247   |  last reply


Friend's new website

My friend just made a new website. It is for Lego lovers. Check it out . it has tons of neat pics. Here's the link http://www.legoka.weebly.com

Topic by bumboozer   |  last reply