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February 23 above on this page has the latest schematic of the revised 3A lab power supply.

Does anyone has LM3914 pspice library? i desperately need it..pleeeeease!

I want to apply force for an extended amount of time (10 secs to a couple minutes) using a solenoid actuator. Unfortunately, it seems that solenoids use a lot of power when they are active. Is there a solenoid type that will only use power when switching between active and not active? There's probably a way I can do this with an external mechanism, but I was wondering if there may be commercial solenoids that have this built-in. Thanks, Jessica

Illegal content (ebook/magazines/software) will be deleted without any notice. Thanks

Hi TJBraza, http://www.analog.com/UploadedFiles/Data_Sheets/ADT7485A.pdf Although, it will probably require a small program written in C or Visual basic to convert the string MSB & LSB into a more easier read etc... Take a moment and review the data sheet, the IC has a lot of potential.

I can't find SL100 & SK100 transistor :'( Which transistors can replace these? Thank you for your help~ ;)

Calm down people. It is not Mixos's fault, if it is against the law he has to remove the content. This site is very good for asking electronic related questions, I have yet to find a better one.

Perhaps the chip is over heating with to much current draw? Try connecting only two motors to see what happens. For the l298n chip itself: For the IO Peak Output Current (each Channel) – Non Repetitive (t = 100ms) 3.0A –Repetitive (80% on –20% off; ton = 10ms) 2.5A –DC Operation 2.0A TOTAL DC CURRENT UP TO 4 A

The board is made very precisely, it's clean and very pleasant to touch. Markings on the silkscreen layer are very good readable. Soldering does not cause trouble, tin adheres very well to soldering points with a small amount of flux. It is also worth mentioning that the PCB is very robust to desoldering. The company is very solid, although you order 10 pieces, you get at least 1 PCB more for test, prototype, present, etc. When I signed up for an account, I also got a $20 coupon for free. Excellent construction and assembly work done by PCBgogo.No problems encountered, highly recommended.

One 2N3055 transistor overheats in the original circuit that used a 24VAC transformer and produces 25VDC at 3A. Therefore I used higher voltage opamps, a 28V 4.2A transformer, a more modern driver transistor Q2 that can be cooled well and two 2N3055 transistors to share the heat on a very large heatsink. Some people added a fan and a smaller heatsink instead of a huge heatsink. If you connect the two 24V windings of your transformer in series and use the centertap as 0V then its output voltage will be 24VAC x 1.414= 34V minus the 1V for the two rectifiers then the supply voltage will be too low because the circuit needs a 28VAC transformer. Your transformer voltage is too high so it cannot be used for this project. Or you could parallel the two 24VAC windings or with the centertap as above then the maximum regulated output voltage will be 25VDC at 3A.

The original defective circuit had many overloaded parts that will blow up. The improved version fixes it. Opamp U3 senses the output current in R7 and reduces the output voltage and output current to match the current set with P2. The maximum output current is 3.0A in the improved circuit and the two output transistors have a total maximum current rating of 30A so they will not blow up with only 3.0A.

Hi, Just build this power supply. Works Ok but will blow output transistor instantly if output is shorted ! Any suggestion

Hi Youkito1991, Nice work!. Thank you for sharing your design and make the PCB available for anyone who wish to use it. Your description is nice and also the support of pictures is very useful. Regards, William

I am a regular PCB designer. Check my designs specimens. If you have such inqyiry in future then e-mail me at abid369@gmail.com or call on +923214322695 Sample Designs.zip

I ordered a set of PCB on https://www.jlcpcb.com for a short run production build。 The quality of both the boards and the stencil are great. just cost me 2$.

The clipping circuit does not have energy storage elements like capacitors but it includes both resistors and transistors. This circuit is normally used for the selection in the transmission purpose. The ability of diodes to allow the flow of current in only one direction. A diode is best tested by measuring the voltage drop across the diode when it is forward-biased. A forward-biased diode acts as a closed switch, permitting current to flow. No voltage exists at the diode but voltage may be present in the circuit due to charged capacitors.

A power supply is an electronic device which supplies electric energy to an electrical load. Can anyone tell me what is the minimum power required 1 ton AC.

The colors of capacitors describe the types of capacitors. The color used to identify the components or parts on the circuit board. The round blue colored balls with dots indicate that its a capacitor. Same as other colors are used for other components.

PCB Manufacturer uses: Front-end tool data preparation, Preparing the photo tools, Print inner layers, Etch inner layers, Register punch and Automatic Optical Inspection (AOI), Lay-up and bond, Drilling the PCB, Electroless copper deposition, Image the outer layers, Plating, Apply solder mask, Silk-screen and cure.

The ebay kit that is a copy of the original faulty Greek power supply on this site is also sold by Banggood and Amazon. Banggood is selling it at a clearance price since they probably had many complaints. They have modified it a little and are selling it again as a kit with a 28V/2A rating and an LCD meter for it. The very nice looking 30V/10A power supply is extremely cheap. Its ad has no detailed spec's. It does not even say if the voltage and current are regulated. If something looks to be too good then it probably is not true.

You forgot to say if the 10V output from your power supply must be AC or DC. You also forgot to say if the input is AC or DC and its voltage and frequency. Did you know that the output power from your power supply will be 10V x 1000A= 10000 Watts? Where will it come from? What will it be used for?

You ask for a lot! Start with Ebay.com for transmitters and receivers: see: http://www.ebay.com/itm/Mini-88-108MHz-FM-Transmitter-Module-Wireless-Microphone-Dictagraph-Interceptor/141659602950?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40832%26meid%3D5caec1e4bbe74e2fa065b6379434198a%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D111649741072

I am trying to make this KITT's dash compass andi have the leds and using a microcontroller to power them but need help on how to wire them so i use the least amount of conponents possable. I thought of darlington transistor ic's but on the 4 10 led bargraph onesi think both anode n cathode will need darlington transistors. 4 1 for either common cathode or anode and 10 more for the other lead for make the patterns. I might be able to use 1 darlington transistor ic to make the yellow triangle leds work using just 4 i/o pins, but i think i need 14 for the red bargraps whats the best way to wire the bargraph leds up? Thanks. Joe

How many digital IO lines do you have on your microcontroller? and how many LEDs do you want to drive?

Here are two SPICE models found online that will simulate the main IC functions including:- a) bar/dot mode selection, dot mode carry for cascaded ICs, c) resistor-programmed hi/lo reference voltages, d) output current selection, e) non-grounded V- and divider ladder, f) independent V+ and Vled, g) leakage current of outputs, h) segment overlap and i) supply current variation with V+ and Vref output load. This model is build by user "alec_t" at electro-tech-online.com forum. LM3914.zip LM3914asc.zip

A schematic would help us to answer the question. I wouldn't recommend either. A MOSFET would probably be better.

You need to be more specific about your project, so we can help.

"A solar charging system is not complete without an appropriate charge controller. Most units include a charge controller to charge 12-volt lead acid batteries and inverter for drawing power. Charge controllers are also available for lithium-ion to charge 10.8V packs (3 sells in series)."

The output of a preamp will produce clipping distortion if the input level is too high. The pickup from an electric guitar produces a level much higher than an FM tuner, a CD player or an MP3 player. Most preamps for a guitar pickup use a Jfet because of its very high input impedance with a gain of only about 1.4 times.

A solenoid is just a linear motor therefore with no power you have no holding torque. You can get a mechanical assist with some via a spring but unless you want to hold open when the power is off and release when power is on I don't think this will do you much good. I think what you'll be after is some sort of mechanical solution beyond just the solenoid itself.

Continued

The current rating is not a problem. It's better to go higher than lower. Using a power relay to switch low current signals is only a problem at very low voltages. The problem with using a lower voltage relay is the contacts can arc over and what's worse it it could be unpredictable.The relay may seem fine most of the time but it could suddenly arc over due to ambient ionising radiation.

thanks hero999 is there any formula for this issue? my coil is 57ohm

TOYOTA Car indicator flasher part number TOYOTA:81980-50030.

BTY79 NTE Replacement BTY79-800R = NTE5531 BTY79-600R = NTE5529 BTY79-500R = NTE5529 BTY79-400R = NTE5527 NTE Datasheet http://www.nteinc.com/specs/5500to5599/pdf/nte5520_31.pdf C106D = NTE5457 NTE Datasheet http://www.nteinc.com/specs/5400to5499/pdf/nte5452_58.pdf Try these suppliers Digikey --- http://www.Digikey.com Mouser --- http://www.Mouser.com Newark --- http://www.newark.com MCM Electronics --- http://www.mcmelectronics.com

No, lead acid batteries are far too heavy. I was looking at maybe NiMH or more likely some LiPo batteries commonly used on RC cars and the like. Looking at 3-6AmpH class batteries. Might lean towards 12V, since there is so much standard stuff for that as far as wiring and other components. Safety is of course important and any good suggestions on grounding/shielding are welcome and appreciated.

Possibly a flyback converter? They can usually be output current limited by limiting the current availiable to the transformer. Do you need it to be highly efficient or are you not too fussed?

[i would not encourage children to develop high tech weaponry and would firmly discourage them from using them on themselves or others.] I saw a project online once that took a page from the XREF taser shotgun rounds, concept. It used pressurized air to propel a charged disposable camera capacitor, prongs first out of a simple barrel. Interesting concept, though from what I read, the 330V would be far to little to achieve the taser effect. That and I understand a specific waveform is needed to affect strictly skeletal muscle and not cardiac muscle. Seems like a safety concern to me.

so let me get this right. Theres a slight power difference in one Tda2003 to another even though there the same. but with a 8pin dual amp would work better cause there together in one IC.

You are breaking the hearts of all the hobbysts who can not afford the cost of buying the books from amazon. most of us are ametures using the books for refrences or some other information. i dont think someone is making millions using these ebooks.

What about links to "illegal contents" like, Can we use rapidshare or other sites to upload such illegal contents and then provide links through e-lab?? (As Elektor magazines thread hasn't been deleted)...... Books posted by Ante were really beneficial and one of the best features of e-lab.....Anyway, legal problems can't be ignored.......

I am very sad too :-[ [move] :'( :-[ :-\ :'( :-[[/move] No doubt, ER has been the one of most attractive features of the site. All the thanks and respect goes to Mr. Ante for such a good contribution to this part of site. I now request MIXOS to leave the contents as it is not reasonable to throw away ones friends(books).

MP, Just click on

Full demonstration: https://youtu.be/UAhRkiLHXDQ

Here is my first blog on electronic product.

No never remove the fuse from the meter. The meter's insulation is only 1kVDC, if you try to measure 100kV, an arc will jump through the case which will both damage it and you'll get a nasty shock.

I have deleted many posts to prevent the frustration when finding posts with a headline of interest just to find “deleted by admin inside”!!! ??? ??? ??? I can’t see any reason to have a moderator for this board any more, just delete all of it and there are no problems! Over and out!

Here is what I have [attachment deleted by admin] SONY_PLAY_STATION.PDF the-ultimate-playstation-manual.pdf

The Hafler opamp circuit should do what you want. The New Japan Radio IC datasheet doesn't explain what it does. It has graphs showing bass-frequencies-only, some phase-shift amounts and its block diagram shows a subtraction circuit for both channels but doesn't show what is subtracted.