Hero999

Why would it make a difference? The diode only drops 0.7V to 1V. It's the fact that the bulbs only conduct for half a mains cycle that reduces the power dissipation. A diode is also the most economical solution for such a cheap set of lights.

Audioguru is right about using a diode, just make sure it's rated for at least 200V. The only trouble with adding a diode it might make the lamps flicker.

It always seems to be abused by spammers advertising their cheap Chinese crap rather than genuine hobbyists who want to get rid of their old test equipment or surplus components.

Good you came up with a solution. Thanks for returning to tell us about how you did it, most people don't bother.

Yes, you need to add a resistor or replace all the bulbs with 8V ones. If you want to use a resistor, you need to know the power/current consumption of the bulbs. The resistor also needs to have a high enough power rating and will probably need a large heat sink. Another option is to power the lights from a 50V transformer.

Look closely at the schematic and the PCB; the nodes the traducers are connected to are clearly numbered.

It depends on what you're driving? If it's a very low impedance load, <600R then use an audio amplifier IC, LM386, TDA2003 etc. for the output stage.

Look at the datasheets of the ICs listed by audioguru. Build an amplifier with a couple of transistors and compare its performance (in terms of distortion) to the op-amp equivalent and see for yourself. Study op-amp theory and negative feedback and you'll see that if an amplifier with a high gain and some distortion can become a low gain amplifier with virtually no distortion when lots of negative feedback is applied.

When you need help with a project on this site, please help us to help you by posting a link to the project. There are hundreds of projects on this site; most people aren't going to bother searching through them to find the one you're talking about, more often than not your post will be ignored. There are many projects that do the same thing: suppose someone asks for help with the audio amplifier project. Which audio amplifier project? It's just easier to post a link: copy the contents of your browser's address bar, whilst you're visiting the project you need hep with, and paste it to the end of your post. Right click in the address bar or text box to bring up the copy/paste menu, see the attached for more help.

Help us to help you by posting a link to the project you need help with.

Please speak English, sorry we don't understand nonsense.

Look at the datasheet or the bulb for a marking. Apart form that there is no other way to accurately determine the operating voltage for a bulb other than to do an experiment: connect the bulb to a a variable voltage source and increase the voltage until the light produced by the bulb, is the same colour as another bulb connected to the correct voltage source.

Please don't create duplicate threads and keep questions regarding the same project to one thread. I've merged the ferrite antenna question with this thread and deleted the duplicates. Moderator

http://www.amazon.com/Koolatron-IR-Remote-Switch-Socket/dp/B0006II7D8 http://www.tradekey.com/ks-remote-control-socket/

It still seems like there's some suspicious code on this site. Maybe the trojan has damaged some scripts so they crash IE and give errors in other browsers? Clicking on the reload button invariably clears the error and it loads properly. I haven't tried the home page yet. I can't get http://www.mypagerank.net/ to work - I temporarily disabled Adblock which might have been blocking it.

I thought the gate was driven from a PIC connected to the regulated 5V supply.? Please post a schematic, there's no way I can help you unless you tell me the full story. Yes the gate is the most sensitive part of the MOSFET and it's also highly likely that the TL084 will be killed by the high voltage spikes.

Do you have a diode in reverse parallel with the coil? MOSFETs can be pretty tough, most can happily breakdown and absorb a small amount of energy. without being destroyed. The MOSFET is rated for over 8 times the supply voltage so it should be fine as long as you have the free-wheeling diode correctly installed across the inductor.

I don't know much about this but I imagine that if the crucible were made of a material with the right electrical impedance it could be done. If the material that's too good an insulator won't work because it won't absorb any energy and it'll just pass straight through, if it's too good a conductor the radiation will most likely be reflected. Try graphite, if it's too conductive graphite-ceramic composite. Another idea is to use a ceramic crucible and to impregnate it with a tungsten filament, an electric current will be induced in the filament, causing it to to heat up. The filament needs to be of the right dimensions to be most effective. Disclaimer: I'm no expert in this filed.

Got to love the joys of Windows and Internet Explorer. ;D Do you have all the updates installed and are you using Internet Explorer 8? I agree, next time you might not be so lucky.. I'm still getting the same error: this time I'm using Firefox 3.5.5 on Fedora Core 11 Linux.

You don't need a current source: use the power supply as the A/D reference and connect the the thermistor as part of a potential divider. Self heating won't be much of a problem as long as you keep the power dissipation low. I doubt you'll find an IC, high accuracy, low voltage and low cost are not compatible.

I've installed no script. https://addons.mozilla.org/en-US/firefox/addon/722 This extension blocks all scripts on all sites except the ones you white list which will prevent any malware from being installed, even if your antivirus program doesn't detect it and there's an exploit in Firefox. This extension also block those annoying pop up links. I also use Adblock plus so all those annoy adverts were blocked before I even installed NoScript.

This probably has something to do with the error I've been receiving occasionally, nothing bad happens, the site just stops loading. http://www.electronics-lab.com/forum/index.php?topic=19340.0 I don't use Internet Explorer because I don't trust it. I think I'll disable scripting for this site on my Windows install, just as a precaution. That reminds me, I'll have to install the script blocking extension. I don't run memory resident anti-virus because it's too much of a recourse hog:, using restricted user accounts under Windows is normally enough to stop most malware and Linux is pretty malware-proof. I'll run a manual virus scan and see if I find anything as I occasionally visit this site in Windows. By the way, you should never trust anti-virus software 100%, what happens if a virus is new and the anti-virus software vendor doesn't know about it yet? You have absolutely no protection! Even whe best AV software only detects 90% of all malware.

Is the 3A load the field coil of the dynamo? You shouldn't need any surge protection - it's just a coil, adding an inductor would just increase its inductance and give you no benefit. The semiconductor regulator, is the only component that will require any protection.

Follow the links below my previous post, pay most attention to the second one and you should know enough to do it. If there's anything you don't understand, don't hesitate to ask.

I get the following error when downloading image attachments: Content Encoding Error The page you are trying to view cannot be shown because it uses an invalid or unsupported form of compression. I am using Firefox 3.5.4.