Reversed Bias Diodes?

I really want  some clarity on "reversed bias diodes" whats the point of having a reversed bias diode? when would a person want to apply it to a circuit? if current can't flow through it, wouldnt it just mess up the circuit? Please shed some clarity on this subject for me, it would be greatly appreciated! -Grizzly

Posted by Grizzly_Bear 5 years ago


diode change

I'm building a picmicro programmer, and I'm fcollowing the schematics from this from sparkfunhttp://www.olimex.com/dev/images/pic-pg2c-sch.gifthey want a BZV55C5V1 diode, but the closest thing that I could find on mouser was a BZX55C5V1 diodehere's the link for the BZV55C5V1 datasheet, just click one, they're all the samehttp://www.datasheetcatalog.com/datasheets_pdf/B/Z/V/5/BZV55C5V1.shtmlhere's the link for the BZX55C5V1 datasheethttp://www.fairchildsemi.com/ds/BZ/BZX55C5V1.pdfPROBLEM SOLVED THANKS TO THE CITIZENS OF INSTRUCTABLES

Posted by guyfrom7up 10 years ago


Help me read this diode!

Hey guys, I just tested a few diodes and they all seem to be blown (reading 5Mega Ohms in forward bias direction) I was able to find the part numbers for all but one. The one in question only shows the following on it: "4.3A  3A" The 4.3A is in slightly larger font than the 3A Does anyone have any idea what this could mean? This one gives me NO resistance value at all. Any help would be appreciated. Thanks!

Posted by daveman2010 8 years ago


diode logic

I'm making a giant adding machine using only resistors(miscellaneous), switches SPST (for input) LEDs (for display) and diodes(for logic). NO TRANSISTORS I have it so that it can recognize 0,1,2,3,4,5,6,7,8,9, but if it recognizes 8, then it recognizes it as all the other numbers. If it recognizes 0, it recognize 1, and 7. If it recognizes 6 it recognizes 1, and 5. If it recognize 9 it also recognize 7. If it recognizes 3, it also recognizes 7. basically if you take a 7 segment display, any number on it, it'll recognize all the numbers in the number. I need help sorting it ou so that if it recognizes 8, it only recognizes 8. If it recognizes 3, it only recognizes 3. Etc...

Posted by guyfrom7up 10 years ago


Where to source quality LEDs?

Does anybody have suggestions where I can get quality LEDs?  I'm planning to build something using 1-3W diodes, and I see a lot on Ebay, but not sure what I should be looking for when deciding.

Posted by awascholl 4 years ago


Laser scanner laser diode

Can I extract a laser diode from a scanner. If so will it be as strong a if I got one from a DVD burner/player?

Posted by laserblast 9 years ago


tunnel diode,s

Can you tell me a place that sells tunnel diode,s? I found one tunnel diode in a jvc radio but I lost it.:-( can you tell me the best free schematic drawing programs for Win XP,also.Thanks

Posted by maker12 10 years ago


red laser diode

Http://www.metacafe.com/watch/948616/how_to_build_a_high_powered_burning_laser_pointer/can anyone send me the link or what i have to do to buy this diode as this young man did David

Posted by Dystonia 10 years ago


Type of diode

Hey everyone, I recently had an ASUS laptop to repair and after troubleshooting, found some damaged components among which is this surface mount diode (kindly see picture). I looked around for a datasheet but cannot find anything. Am also unable to find out exactly what type of diode it is from its code marking. I've had results varying from a 'leakage diode' to '3.3V zener diode'. However, I am suspecting it might be a schottky diode since it was in what looks like a boost circuit. Any help would be greatly appreciated. Code marking: 100 98FP1  j Thanking everyone in anticipation. Kind Regards, Nawaz

Posted by Nawaz 3 years ago


Diode Calculator will not work

I've been working on a diode only (well, plus switches for input [numbers, yet there's only one pad! not one for each digit], resistors for various things, and LEDs for the display) calculator that could add two two digit numbers (xx+xx=xxx) for a while, putting countless hours into it.I have deemed it impossible.There's so many problems with a mass diode resistor network that is just won't work. As some and gates conduct then some other gate (like it's suppose to) conducts, and eventually causes a voltage divder (with the pull up/ pull down resistors) and the output gets wacky and there's no wway of amplifying the signal.The diode adder is dead

Posted by guyfrom7up 10 years ago


Zener Diode to regulate solar voltage

I'm new to electronics, and I'm having trouble with varying voltage. I'm running a 6V solar panel through a charge controller, and out to a lithium battery (3.7V) and a load (3.7V), in this case a GPS data logger. My issue is the varying voltage to the GPS. The GPS works perfectly off the battery (constantly diminishing voltage), but when the solar panel kicks in the voltage increases, the GPS thinks it is being charged, and switches off. The GPS will work on any voltage above 2.75V I was wondering if I put a 3V zener diode in series between the charge controller and the GPS, would this keep the voltage at a constant 3V even if the solar panel is producing the 5V needed to charge the lithium battery?  I hope this makes sense Thanks

Posted by blakea 5 years ago


Laser Module Time

So I ruined my second laser diode in a row, and I am just sick of trying to solder on to these tiny leads. I get these things off ebay, and I think they just scavenge them out of broken Bluray burners or something, because the leads on them are tiiiiny. So instead, I think I will just buy a laser module. I found a pretty good 250mw blue one on ebay for 53 bucks. Does anybody know a dedicated hobby website though? One that might have better prices? I don't need a laser pointer, because I already have my own circuit set up and stuff. Any thoughts?

Posted by thedonquixotic 7 years ago


Diode question

I need help with diode. Actually a question: if you put diodes in series for example 2 diodes of 300 V will they act as one diode of 600 V?

Posted by Dantex 10 years ago


Laser diode

I need a laser diode from 18x or more dvd writer or blue-ray writer.please help me.I dont have a credit card to buy them from e-bay

Posted by Rhsameera 8 years ago


Laser Diode Pinout. 4 pins??!!

Hi, I got a DVD Player at an auction, in fully working condition, for $10. So, since I already had one, I decided to remove the insides, and extract the laser diode within. I did so, expecting to have just a normal 50-200mw 3-pin red diode. Instead, I have a 4-pin diode, of unknown wavelength, color, and power. Would anyone happen to have a pinout for it? The pins are arranged as below in the picture.

Posted by metrogdor22 8 years ago


Laser pointer diode

I was making a laser trip wire, but I was looking online for diodes which I found, by which one would be best to get, I dont care for the color, in fact I am better off with red and the intensity can not put off heat to harm anyone. Anyone have any laser diode recommendations or have a site that I can buy them from?

Posted by bprins 6 years ago


Determining values for zener diode

Hi guys, I am quite noob in electronics. I would like to know how to determine resistors and zener diodes values for a battery life indicator similar to this :https://www.instructables.com/id/9v-battery-status-indicator-circuit/ And if I want to use a battery source of 1.5V, how will the values change? Thanks!

Posted by kurtselva 5 years ago


Blown Circuit Identification

So I am trying to repair an old hair straightener so that I can use it for some project on another. Part of the circuit blew. I think it was a diode but am not 100% percent sure. If someone could let me know what the part is so that I can possibility replace it.

Posted by Trenyx 7 years ago


Diode laser cutting capabilities??

Hey guys, Im starting to build a 2 axis CNC for a laser. I was going to try the DVD burner laser and just cut through some paper for now but im wondering what the capabilities of the higher wattage lasers are. I know there are several 1-2+ watt lasers on ebay, what could they mange to cut through? Could I cleanly cut cardboard? What about vinyl for making stuff like decals and stickers? Im wondering if spending the extra money on a better laser would be beneficial or not so if anyone has some good comparisons or ideas let me know. Im on a tight budget for this build so a co2 laser is WAY out of the question. This is my first CNC build so its mainly to learn but the more capabilities of the CNC the better.

Posted by jdavis-9 5 years ago


Need some advice in connecting/powering a bunch of Laser diodes.

I have 25 Laser Diodes that I want to connect up together & test out. They were all supposed to be: 650nm, 5mW, 5V, but in the small box they came with, there was a thank you letter, which listed them as 2 - 5 mW. They were pretty cheap & it wouldn't really be worth my while to return them so am gonna have a go. Since I know he-haw about electronics I was hoping for some advice to get me going! 1) How do I connect them all up together (they all have 1 blue & 1 red wire each, I'm thinking all blue together & all red together)? 2) I'm looking to run them off batteries (AA, AAA, 9V etc), so how many would I need to get it running properly as I don't want to burn the diodes out or anything like that? I know this will probably be an uber easy question to anyone with a hint of electrical experience, but I figured this is probably the best place to ask for advice. Cheers, Jonny.

Posted by mastini 6 years ago


Negative Ionizer

Hello. I want to make a negative ionizer. Someone could give me a circuit that you know works? Greetings and thank you all! This is a very bad google translation.

Posted by erdosain9 6 years ago


Name those DVD Burner parts :)

Hi guys and gals, I just ripped apart a broken pioneer dvd burner of mine (digging for the laser diode inside) Apart from some nifty fans, motors, springs etc. I also came across these inside the reading/writing head of the burner. One definitely is a laser. But as often pointed dvd burners tend to have multiple (2) lasers. Now I wonder which of these items is the second one? All of the three upper items were pointing inside the head and (via some mirrors and lenses) towards the lens shown at the bottom of the photo. So they all seem to be involved in either creating or receiving (reading sensor?) of the laser beam. Hope some brave soul can give me some hints on these.

Posted by userman 9 years ago


500 Glass Diodes

Selling 500 assorted glass diodes. To purchase go to "http://cgi.ebay.com/500-Assorted-Glass-Diode-/260660715619?pt=LH_DefaultDomain_0&hash;=item3cb096e063#ht_500wt_1154" Thanks

Posted by tinstructable 7 years ago


Diode Help

Hi, i have a bunch of diodes laying around, can somebody explain the diode function on multimeter? sure, there's numbers on the multimeter, but what do they mean? maybe give me a formula? Thank You!

Posted by Sandisk1duo 10 years ago


Photodiode

I need this project details : Assume that your photo diode is connected with Micro-controller (any) and micro-controller o/p is displayed in 16*2 LCD. Write a program in Arduino IDE for measuring light response of photo-diode into voltage, absorbance and transmittance. Display these parameters in LCD.

Posted by AyushJ39 7 months ago


Help me with choosing proper diode for my solar panel battery charger

I am have two of these solar panels:http://www.flexsolarcells.com/index_files/OEM_Components/Flex_Cells/pages/Flex_Cells_Individual_06_SP42_37.phpVoltage4.2 VCurrent22 mAVoltage (oc)5.9 VCurrent (sc)30 mAI have connected the two in parallel for more current. I am making a charger for 3.7V mobile battery. What would be the most appropriate diode to use?Thanks for your help.

Posted by huzefa 9 years ago


incandescent light flicker hacks

There are 2 hacks with incandescent lights that make flickering effect. may be usefull for some haloween stuff here is the most basic description. if you build it be carefull in fire safety - some stuff may overheat and blast / catch fire. use non flammable boxes if needed. starters and diodes may explode if connected incorrectly - always protect your eyes do not do any of the hacks with CFLs - they are for incandescents only. they may work with LED lights depending on other components in the ciruit and the amount of current (if there are capacitor / induction / electronics / transformer in the LED circuit then dont do it) hack 1 - slow flicker (i saw it somewhere on instructables before) connect the incan in series with fluorescent lamp starter (the neon discharge type) you may connect 2 starters in series. i'd expect longer outages this way. if they dont light (not enough voltage) then use the starters designed for 2 x 18 W fluorescents. warnings dont connect the starter (or series of 2 or more starters) directly across the ac source. the starters will blow immediately and may explode. check that in any possible path through the starters there is an incan light dont connect stuff in parallel unless you really know what you do. lights connected in parallel take the sum of the currents they take on their own - anything more than 1 light is too much for a starter (or any amount of starters in series - each gets all the current) part 2 - fast 50 Hz flicker connect the lamp in series with an 1N4007 diode. the diode blocks 1/2 of the ac wave and makes some light flicker. seen best in low watt lamps with thinner filament (with less thermal capacity) diode may be used together with starter to combine the effects this hack is used widely in heating appliances that have 2 heat settings. in the lower one they are connected thru a diode

Posted by 11010010110 9 years ago


Solar Panel System Circuit Check, am I right?

Okay so I'm about to start putting together a small Solar Charging Station to charge most of my small battery devices and I want to include a usb port to charge ipods and such. My system before integrating the usb will use a panel providing 12V to a 12V battery through a charge controller. The battery would then power devices through an inverter. I was planning on hooking up a 5v voltage regulator and 220uf capacitor in parallel to the battery and charge controller. My main concern is: Will any problems occur when hooking up a 5v device with a smaller battery in parallel to the other 12v battery through a voltage regulator? If so, how could i change the circuit to be safe and still allow for the usb port? Also would the use of a switching diode be of importance here? Thanks for the help!

Posted by blindsided 10 years ago


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?

Posted by kelseymh 9 years ago


Do I subtract the voltage?

So I was reading in my electronics for dummies book and it said there is about a 1.2 volt drop when using a standard LED. So, when calculating a resistor, with say a 9v battery, in my equation, do I make it R = (7.8 - 3) / 0.02 ? Instead of using 9v in my equation, do I have to subtract the voltage drop first?? Thanks! ~electricloser

Posted by HavocRC 5 years ago


Reuse the LED from a TV Question?

I had an LED Tv break and I decided to remove the LEDs out of the TV and reuse them as background LEDs for the new TV.  The issue that I am running into is that I can't figure out how to power them on.  I know they work because i can get a segment of 3 to light up by using wires connected to a 12v battery.  Each strip has 57 LEDs and a 4 wire connector.  I was guessing that this means it is a RGB strip, but there are nothing but +/- symbols on the strip so it is confusing as to what the wire does what on it. I would appreciate any help that anyone may have for me.  

Posted by RyanL3 3 years ago


Problems with Laser Module Diode

So I have a 5mw laser diode module that I am trying to get open so that I can install a 250 mw diode in its place. Problem is, the diode won't come out, the manufacturer glued it in, and I keep buying new modules from different sellers only to find inexplicably the stupid diode backing slathered in glue. Is there a way of getting this thing out? I don't care if the diode is broken, I don't need it, but I want the driver intact.

Posted by thedonquixotic 7 years ago


Rectifier Diodes

My friend took apart his broken Kenwood amplifier. He used his multimeter to find the broken part,  then removed the RM4Z rectifier diode. I've been searching for about an hour, but I cannot find any websites that sell the RM4Z diode. The closest I have found was one from Hitachi, but I read that the RM4Z was from a Chinese company. Suggestions?

Posted by freethetech 6 years ago


How to Use Diodes to Harness Mulitple Flows of 4 5 Volts Earth Battery Telluric Current Electricity Generated

Hello, We can generate 4.5 currents using an earth battery in Kpalime, Togo, West Africa. I want to combine 5-10 of these together, and stop the electricity from going both directions using a diode. Do I need a special diodes? How to couple many earth batteries of 4.5 volts together to create higher volts?. I am Andy Lee Graham of HoboTraveler.com http://www.hobotra veler.com/blogger.html  

Posted by hobotraveler 2 years ago


Changing the sensor

Hello guys, I want to make this circuit I just don't want any light to be visible. So, I was wondering if I could just change this LDR sensor to a IR sensor and still get the desired results.  Thanks,

Posted by HavocRC 5 years ago


Help repair - identify part (diode)

Hi, Need help identifying this part. It is part of binary input stage, and is not working. I think it is diode, but not sure.  If You know what this part is please help. Thanks.

Posted by apofview 1 year ago


Fading LED Circuit

GOAL- My goal is to light up a small model I have using an LED circuit that will automatically fade in and out. DESCRIPTION - I will be using 19 blue LEDs (3-3.2V fwd voltage, 20mA fwd current) and would like them to fade in and out on their own very slowly. I am thinking that this will be powered using a phone charger or other household transformer since batteries don't seem to be a feasible option for this (too many batteries clustered together and/or too short a life span). I have a transformer on hand that runs 5 volts at up to 850mA, so if that works then perfect, if not then I could try to find another transformer. For the sake of simplicity I could add one more LED to make it an even 20, though I would have to drill another hole in my model. TASK - I need the circuit to make these LEDs do their fading. Simple as that. Fading circuits are easy to find on the internet, but I have been having trouble finding anything to meet my project criteria. Any help with this would be immensely appreciated!

Posted by Andrew Wiggin 4 years ago


Scrounging Electronic Components

Old PCBs (printed circuit boards) used to be a great source for electronic parts. Especially if you need a power transistor, MOSFET, voltage regulator, big capacitor, or reed relay which is not available locally. It just does not pay to mail order small numbers of parts, so having a grab bag assortment at home is handy. But I have noticed that the some higher-quality PCBs just loaded with cool parts can be hard to scrounge from: 1. They are double-sided, or even multi-layered, with copper plating right through the holes (vias) so it is like pulling teeth, only harder. 2. They use no-lead (RoHS) solder which needs high temperatures to melt 3. They use surface-mount components and good luck removing and using those. I use 15 watt, 40 watt, soldering irons, solder sucker, solder braid, flux, and a soldering gun. And for some items, a small windproof butane "jet engine" lighter as a mini torch to remove multi-pin items. Just heat-sink the legs and bang the hot PCB down to remove lots of solder at once. Of course I use gloves, safety goggles, ventilation, and proper recycling. But the main issue is that it is getting harder to scrounge parts to build up a pile of useful stuff.  What resources do you use?

Posted by iectyx3c 7 years ago


Where can you buy laser diodes and circiut drivers ?

Laser DIY didn't send the parts we needed do you know where else to get  laser diodes and circiut drivers for the cheapy lighter laser burner ?

Posted by saltwaterfarmtoo 8 years ago


Blocking Diode Recommendation

So I want to charge some rechargeable batteries with some solar cells I bought and I heard I should use a blocking diode to prevent the batteries from discharging at night. I have 3 6V, 50mA solar cells in parallel for a 6V, 150mA total. Does anyone have a recommendation for the model number or kind of diode I should use? Preferably one with a very low voltage drop. Or is my solar setup too small to require a diode? I have never done this sort of thing before, so any help would be greatly appreciated!

Posted by msh21 9 years ago


LASER HACK: DVD burner diode list

I propose to put your results of using the DVD burner diode for using as POWERFUL laser pointer: See the instructable: Laser-Flashlight-Hack!!/This allow sharing the experience and avoiding some bad burners...Put your-DVDburner BRAND and -MODEL and finally the -RESULTS

Posted by wazza 10 years ago


Need Data Sheet for old diode laser. RCA SG2001

I have been digging though my assortment of electronic components, stuff that has gathered dust for years.  One item I came across still new in the original package is a laser diode.  RCA # SG 2001.  I have tried searching internet with out much luck other than a PDF about how to drive the diode.  ( short pulses high current ) I see the same part number referenced for other products.  I did find it listed but there is no data showing that I can find.  Yea...it is over 30 years old !  No reason not to know what it is or what it could be used for, perhaps for the pocket engraver? Would much appreciate any information anyone may have about this chip.  I believe it is fairly high power IR diode.   It is stud mount with a single lead exiting the center of the stud bolt.  A bit less than 1/4" dia case.

Posted by stuffdone 5 years ago


Zener diode Regulator Assy

I am in need of assitance for assembly instructions for building a 5V power supply from a 12v power supply using axial components. I am not sure of the orientation & solder method of components. Thanks for any help. MCD

Posted by mcoanarmen 9 years ago


Zener Set Voltage Signal Circuit (help)

Hey Everyone- I have been researching on ways to send out an electric signal to trip a relay to shut off my battery charger. I did find some simple circuits and I did the math for what I would need and could not find big enough zener diodes and resistors. Battery+(Resistor)(Zener Diode)(Relay Input)(Battery-) I need this circuit to send a 8.2 or 10Volt 15mA signal to my Relay when the batteries reach 235 volts. Following are the SPECS for the Input signal on my Relay::: Control Voltage Range 3-32 Vdc 90-280 Vrms (60Hz) 18-36 Vrms/Vdc Max. Reverse Voltage -32 Vdc - - - - - - Max. Turn-On Voltage 3.0 Vdc 90 Vrms 18 Vrms/Vdc Min. Turn-Off Voltage 1.0 Vdc 10 Vrms 4.0 Vrms/Vdc Nominal Input Impedance 1500 Ohms 60K Ohms 9.0K Ohms Typical Input Current 3.4mA @ 5 Vdc, 20mA @ 28Vdc 2mA @ 120 Vrms, 4mA @ 240 Vrms 3mA @ 24 V Any help on this would be great Thanks!

Posted by rc_rs_ss 7 years ago


Converting at 9V solar panel output to 5V using diodes and voltage regulators

Hello i was recently sold a solar panel which was the wrong voltage i need to step down the output from 9V to 5 or 6V. I have been given two TA7805S voltage regulators and 6 diodes and told i can do it with these but i don't know how any ideas?

Posted by henrycrone 5 years ago


Laser soldering

So im making a  laser spirograph (https://www.instructables.com/id/Laser-Spirograph/#step1) and i just got my laser diode to come out of its case, and i was wondering where i should solder the red and black wire as it does not look like the one in the 'ible. the laser diode looks like this one here http://10mW 532nm Green Laser Module (3V 11.9mm)  (i would take a pic of the diode but i cant find my camera!) the only difference in the diodes is that mine has a black button instead of the red. Oh and one more thing is that it has to bypass the use of the button. Thanks in advance!!!!!!!!

Posted by Mr. walrus 6 years ago


How much batteri will I need?

Well for my new project im gonna add 50 small diods, how much batteri will I need? Diod info: 1,6 - 2 V 20 mA 5mm Batteri info: A normal 9v batteri

Posted by tiermaster 9 years ago


Quick camera charger question

Before I get started, I've been always posting in this forum section. This is the right section to ask questions right....? I got a camera charger. I want to cut it so it charges A LOT faster (easily proven true) Now. Here's te problem. Most tutorials, show a diode on the board. They say "keep the diode on!" Well, I got 3 circuits. All the same. The problem: The diodes, are on the opposite side of the board. If i cut it like most tutorials say, ill be cutting the diodes off. Maybe other important links. Any suggestions? I thought there was a way to do something similar like this, without cutting the board... Yet still charge fast. Like something doing with bridging a part?

Posted by Killa-X 9 years ago


Focus an LED

I was wondering if anyone knew how to focus more than one LED (infra red) into one tightish (about 1m at 100ms) beam. This would actually be for a laser tag gun that i would like to make an instructable about. The game is based on these high powered infrared leds that are focused by a 2cm-5cm diameter double convex lens assembly. Snipers obviously need further distance and have a tight beam while others have a much wider beam. The focus can be adjusted by moving the led back or forwards. Having more than one LED may lead to dramatic leaps in range (so it is theorised). I have been told to use cube beam splitter but i don't even know what they are. Thanks community any help is seriously much appreciated Thankyou Thankyou Thankyou Thankyou

Posted by DELETED_D4VOBRO 9 years ago


Can I use a multimeter for measure voltage drop in LEDs?

I have a really cheap multimeter, but it has a "diode" position in the main switch. As the LEDs are diodes, could I measure the voltage drop for use in resistor calculations? My guess is "yes", but I'am very new to electronics... Thanks a lot.

Posted by Limadito 11 years ago