Two models will be shown, one full-wave rectified and the other a half-wave rectified negative ion ionizer. Featuring an optional fan on the full-wave model.

Benefits of negative ions supposedly include
• freshen and purify the air
• help lift mood
• alleviate depression including winter depression(SAD)
• eliminate most tiny particles suspended in the air (indoors)

  • HIGH VOLTAGES present in both devices is high enough to induce a bad case of temporary Tourettes. ie twitching/profanity.
  • Be aware of the hazards when working with loose CARBON FIBRE filaments if using this option for high voltage grid instead of pins.

Step 1: Components and Design

Tools required:
  • soldering iron and solder.
  • screwdrivers, flat and star
  • cordless drill.
  • hot melt glue gun.
Optional tool:
  • wire wrapper.
The full wave rectified version has better performance but is a bit noisier if using the optional fan. The fan is a 60mm x 60mm CPU 12 brushless fan which I'm driving at
5v to reduce current consumption and noise.

The half wave version uses fewer components and less current, the smaller size is also trickier to build.

In both versions the negative band on the diode must point towards the ac voltage input.
If you follow the green arrows on the component diagrams, you will first encounter the negative side on the diode first, indicated by the white band.
Nice instructable. I made one of these some 30 years ago. My mum wasn't that happy about it, because the high voltage charges fine dust particles and they are attracted by more or less grounded surfaces like walls and even windows ;-) If you direct the ion flow trough a grounded tube, you have a electrostatic air cleaner. (you can have a thin wire insulated in the center of the tube and connect the high voltage there. As it's done in laser printers.) You can also make a ion propulsion propeller...
<p>Dear Sir,</p><p>I have tried constructing a ionizer 4 to 5 times. But I could not get the result.</p><p>Now I have constructed the full wave ionizer as per your instructions. This time, I got the result. the voltage at the second capacitor itself has crossed 800v.If we bring the line tester near the tip of the pin, even without touching the pin, the light in the tester is glowing. when I move the tester even closer, blue light is coming between the pin tip and tester tip. Does this mean the circuit is working? </p><p>But I could not smell anything. is there any way to test whether this ionizer is working or not?</p><blockquote>Thanks again for giving valuable instructions. <strong><em>Kindly let me know how to test whether negative ions are coming out or not?</em></strong></blockquote><p>Thanks in advance,</p><p>CH M S SARMA</p>
<p>If you can see the tips glowing in the dark and all the diodes are correctly orientated then only neg ions can be present at the output spike/pins.</p>
<p>Dear Sir,</p><p>I have a small doubt. will the tips glow themselves? or we have to bring the tester near the tips? If I bring the tester near the tip, I can see the blue spark between the pin and the tester. and when we bring the tester near the tips, even without touching the pin, the light in the tester is glowing. I have checked the orientation of the diodes and everything is ok. </p>
<blockquote>I can see the blue spark between the pin and the tester. and when we <br>bring the tester near the tips, even without touching the pin, the light <br> in the tester is glowing. I have checked the orientation of the diodes <br>and everything is ok.</blockquote><p>You've answered your original question, its working.<br></p>
<p>I have one more question Sir. suppose we give the central pin to neutral and both the other ends to Line and we will reduce the Capacitors to half. will it give the required result? can we use alpins at the end as emitter?</p><p>Thanks,</p><p>CH M S SARMA</p>
<p>You could try other configs to see which gives best result, anything conductive and sharp can be used for emitter</p>
<p><strong>IT WORKED</strong>.. I have made a circuit of 6 capacitors in a row and given both ends to line and center one to neutral. I can see the blue spark when I bring the line tester near the pin. Also when I brought the tester near the pin from 1cm distance, the light in the tester is glowing. Any problem will have in this design? or I can use this?</p><p>Thanks,</p><p>SARMA</p>
<p>It should be fine, it might just be a lower voltage.</p><p>Leave it on in a vacant room for 1hr or 2 and see if theres a freshy electric kind of smell when you come back in.</p>
<p>Dear Sir,</p><p>Will there by any noticeable difference between full wave and half wave ionizer. can we make this circuit without a Fan?</p><p>Regards,</p><p>CH M S SARMA</p>
<p>Nothing you'd notice, fan not needed.</p>
<p>Dear Sir,</p><p>I have purchased the capacitors and made the half wave ionizer. If I bring the line tester 1 inch near the tip/resistance, the big blue spark is coming. </p><p>Then I checked the capacitors. they are .33nf. I hope the capacitance will not effect the output voltage. Further, when I checked the crockfit Walton voltage calculator, in 14 stages - input V 220AC - capacitance - any - load current .1 mA, the output Vmax is 9kV. Don't you think that this value is very high for generating the negative ions? Interestingly, the output voltage is not changing with capacitance. </p><p>I am not able to understand whether the circuit will generate negative ions or not.</p><p>Hope you will clarify my doubt.</p><p>Regards,</p><p>CH M S SARMA</p>
<p>The output voltage is dependant on the number of stages, not the cap values.</p><p>If your applied voltage is on the negative side of the diode, a negative voltage will be present at the output pins, you can chisel that into rock, right next to death and taxes.</p><p>When the neg voltage at the output pins becomes high enough, negative ions will depart into the surrounding air from any sharp points, low voltage = few ions, high voltage = many ions.</p><p>The only way for you to erase doubt/confusion is through knowledge. </p><p>Experiments will allow you to observe static electricty fundamentals to gain the required knowledge, with that in mind build a simple electroscope to determine that your device emits ions. </p><p>Then precharge the electroscope with a positive static charge, the foils will repel each other, now direct your ioniser to the electroscope, a negative charge from your device will cause the foils to drop/close.</p>
<p>Hey Peterrc</p><p>I have bought a commerce negative ion generator that is rated for 7.5kv. I was wondering if i could use this to make a ait ionizer. When i run it it can ionizns the air but i dont know how i would set it up to capture dust.</p>
<p>I would use a fan on the end to cycle the air through the device, a ground plate is needed to attract the dust which would otherwise be attracted to the walls, ceiling etc.</p><p>The ground plate doesnt have to be inside the device, it can be a stack of several strips all grounded, just in front of the device output.</p>
<p>To clarify the <a href="http://www.imagesco.com/kits/negative-ion-generator.html" rel="nofollow">negative ion generator</a> (last one down 7.5kv) Is only the generator. The generator has a ground terminal. Could I connect the ground to the fan metal grid and then put the pins facing it just like you did but with out a ton of capacitors. Also would it be a high voltage or low voltage systems. I would like to do the same set up but with out the electronics and just replace it with this. Would that be possible. I am trying to better understand how this works so that i can try and implement this other method.</p><p>Thank you very much.</p><p>Ender</p>
<p>Can any body tell me where is the ground for this generator?</p><p></p>
<p>Yes, its exactly how you've imagined it and 7.5kv is very high voltage so be careful that your fingers dont get too close when its on.</p><p>Those 2 wires would be live and neutral and I'd suggest that you use the earth/green wire to the grid. My little fan grid isn't very effective at removing dust particles which is why I suggested the plate stack, more surface area will attract more dust. If you google <a rel="nofollow">electrostatic cleaner</a>, you can get an idea of a starting point.</p>
<p>I made it but when I connect the input to main AC nothing happend ! I didn't see faint purple corona glow discharge at the needle tip ! after that I connected a flyswatter circuit as input and then it works ! I saw purple glow at needle tip in darkness but its sooo tiny and difficult to see ! ( I used a magnifier lol ) ! I don't know why is the performance so poor ? I should say the ground is connected to nothing ! because we don't have any type of earth connection at home ! what should I do to increase performance ?! should I use an inverter with high frequency square wave to have higher voltage in output ?</p><p>best regards</p>
<p>Connect the center input leg to ground. </p><p>I've traced the domestic wiring in my house and checked in the box where it enters the house, the &quot;neutral&quot; is actually connected to the ground spike.</p><p>So with that in mind, perhaps you could hook up the center connection to neutral and &quot;live&quot; to the 2 outer connections.</p>
<p>Hello petercd and thank you for sharing your experience</p><p>I have a question</p><p>can we build an electrostatic air filter with 2 section ( like these pics ) using this circuit ?</p><p>section 1 charging particles with positive high voltage and section 2 collecting them with negative high voltage plates ! and after collecting we put sharpened pins ! </p><p>it seems it is more effective to collect particles if we first charge them with positive high voltage them attract them with negative plates</p><p>thnx alot</p>
<p>Seems like it might work, but I have no real experience with the way the commercial systems are setup.</p><p>Some folks use a grounded foil nearby the generator to attract the dust, being outside the generator makes it easier and safer to clean.</p>
<p>Thank you very much </p>
<p>I'm trying to fix an ionizer. It just stopped working (i.e., fan runs, but no more ozone odor). Does the plate (3&quot; x10&quot; porcelain) have to be cleaned, and if so, how? Looks like it is soldered in there. I'd appreciate your help! Thanks.</p>
<p>Sorry, Ive no idea how those commercial ones are setup. </p><p>Its possible dust buildup on the plates has shorted it out, but bear in mind the caps can hold a charge for quite a while even when its unplugged from the wall socket, ie dont go poking all around inside there, 5000V + can really ruin your day.</p>
<p>A simple question before start. <br>Do Ionizers need to be wired to the ground to work properly? Is that correct?<br><br>Thanks in advance!</p>
<p>They dont really need to be grounded to work, basically the HV builds up the electron pressure in the circuit causing the negative ions to be released from any sharp points, but a ground grid in front of the neg electrode causes the neg ions to be sort of sucked off the neg electrodes, kind of boosts the working.</p>
<p>But i think the ground grid closes the circuit and doesn't let the ions to fly beyond it . Also I'd like to ask, what if i don't use output resistor. Wouldn't it be more effective? because you get more output current.</p>
<p>Its not about the current, its all about the HV. The ions fly beyond the grid and fill a small room fairly soon. You'll smell the difference as soon as you enter the room.</p><p>If you spend too much time in the saturated ion environment, (eg overnight in your bedroom) then your body will attempt to lessen the effects by blocking off one nasal side.</p><p>The resistor adds some safety by limiting the current in case of an accident, ie your fingers getting too close to the HV pins.</p>
<p>Thanks for reply, one more question, What did you put it in? Can i use PVC tube as housing? or it will steal charge and lower the performance.</p>
<p>PVC is fine, its what I used. The plastic has good insulating properties.</p>
<p>Very nice! Congratulations! Thanks for sharing! </p><p>Cristiano, Brasil.</p>
<p>Nice instructions very easy to make!</p><p>so I added 2 fans one sucks air into the box the other blows it out. im interested if you make the ion array bigger does it produce more ions? also I've made mine out of needles would razors be better? the box is just so it can sit out and be incognito! cheers</p>
<p>At some point, with a voltage multiplier, you start going backwards. I presume this is because of resistances and voltage drops in the diodes. Using the same Capacitor values I ran a simulation with 30 &quot;diodes and caps&quot; and compared it against another simulation using 18 &quot;diodes and caps&quot;. Interestingly the shorter one gave a higher voltage output. Using fewer diodes and caps will also cost less. Maybe you could take those savings and buy larger capacitors, that will also bring up the maximum voltage. </p>
<p>While a full wave voltage multiplier can sustain higher voltages under a load versus a half wave voltage multiplier, a half wave voltage multiplier, if constructed with larger capacitors can sustain even higher voltages. Below is just an example of 3 different circuits in a circuit simulator. </p>
<p>I build this full wave ionezer first in a paper shoebox, withouth the fan. I used it several days. On the metal fan protector start to collect the dust. So I decided to move it a final plastic box, and I put the ventillator inside (now it is not working I just put it in to be able, to connect it later).</p><p>But now in the plastic box it is not working as good as before in the paper box. The metal fan protector is started to get a brownish tint layer (as you can see in the attached pic), and very little dust can be seen on the fan protector. What I made wrong?</p>
<p>Be very carefull not to get too close when checking things out, in a very dark room, see if there is a faint pinkish glow on the end of the electrode pins which would indicate that the circuit is working.</p><p> With it unplugged and given time for the caps to discharge, check the earth connection to the fan guard.</p><p>Finally paper is a fairly good insulator so maybe that type of plastic is bleeding off a lot of the static charge.</p>
<p>Thanks a lot for this nice inscrutable. I made a hack to an old one air ionizer which gave life. This way I was able to keep the old case and precious steel metal HV grid.</p><p>I used the half-wave method. It works like a charm. Only flaw is safety which will be worked on later on. </p><p>Now some pic's. There you see the 2 row caps with diodes on the back of the device. Next one is steel neutral plate which is pushed in from side so it is possible to clean those plates. front view w/o covers. Those sharp triangles is the HV tip. Next picture is neutral plates pushed in the device. Last one are old guts.</p>
Nicely done.<br>It seems to have been the trend to pot the HV components in resin back in the day.<br> I think they relied on the resin for insulation and thats usually where something burnt out. :(
Hey Peter CD, still on this? I want to make an electrostatic precipitator for a wood burning stove, will one end of your ioniser stick in the air intake of the stove, with a positive charge sent by co-ax to the collector about 15 feet away? Can the charges pos and neg be collected from the same unit?
nope, neg only, you'd need to build another unit with all the diudes reversed to make a positive charge.
question... how about? : <br> <br>&bull; help lift mood <br>&bull; alleviate depression including winter depression(SAD)
mmmm, dont think so, however I live in Cape Town and have never seen snow here, hailed hard once or twice in the last 50 yrs, basically my point being that I dont get SAD in the first place so Im unable to tell you what would lift it.<br><br>I did notice that on the odd occasion Ive left it on all nite, that come morning left hand sinus is blocked.<br>So it lends some weight to a theory that the nostrils polarize the air positively or negatively depending on the bodys need.
Hi, if after unplugging it, you short the HV output (via the safety resistors) to the AC neutral wire input (or neutral grid), does that discharge all the capacitors (so you don't get a shock from touching the output or the caps)? What is the difference between doing this and shorting the live and neutral of the 220V AC input after unplugging? I am thinking of incorporating a discharge circuit into a switch for the thing so when i switch it off it disconnects the mains power and also discharges the capacitors, but i am not sure which points to short to accomplish this.
<em>&quot;short the HV output (via the safety resistors) to the AC neutral wire input (or neutral grid), does that discharge all the capacitors (so you don't get a shock from touching the output or the caps)&quot; </em><br> <br> <strong>Yes</strong><br> <br> <em>What is the difference between doing this and shorting the live and neutral of the 220V AC input after unplugging?</em><br> <br> <strong>This doesnt short out the caps because the rectifier bridge blocks the rest of the circuit and if you short out after the rectifier you will only discharge one cap</strong> <strong>the others being blocked by the diodes<br> <br> There is a strong discharge when shorting the circuit so its best to use a resistor to do it gently to avoid damaging other components</strong><br>
Thanks, so to discharge all the caps i have to both short the HV output to the neutral terminal, and also short the live input terminal to the neutral terminal? <br> <br>Anyway my plan of having a 2 way switch which shorts the HV output to the neutral end of the cockcroft-walton multiplier when the device is switched off won't work because it would cause arcing inside the switch while the device was on (unless i fill the switch with oil, then it leaks out and is messy). So i am just going to have the switch short out the live and neutral input ends of the multiplier through a resistor when it is switched off. <br> <br>On another note, here are some ideas for other electrodes / ion emitters: A round wire brush of the kind used in drills for brushing rust off metal - the wires are thick and not very sharp, but there are a lot of them, and the places where they touch each other inside the brush also act like needle points. <br> <br>A wire pipe cleaner / rifle barrel cleaner type brush, these have thinner wires so might work better. An ioniser using one of these had the highest ion output count among competing models analysed by the Elrana ioniser company, see this page, it has images of ioniser PCBs: <br>http://www.elanra.co.uk/otherionisers.htm <br> <br>I have also seen razor blades recommended in one scientific paper - the super sharp edge is a brilliant at generating corona at low voltages, and the performance does not degrade as much with wear, compared to needle electrodes. <br> <br>And the edge of thin gold or aluminium foil is also good, especially if it is cut at an angle, or you tear it using the serrated foil cutter on the kitchen foil box. This produces a serrated and thin edge. Get the thinnest (which is usually also cheapest) foil you can find. <br> <br>Also, if you want to maximise corona production (which may also make a lot of ozone though), put a grounded or opposite charged electrode made of fine wire mesh near the emitter tips. The finer the mesh the stronger the effect, due to something about how electric fields behave when going to conductors shaped like a plane with slots.
Eventually I upgraded both to the carbon fiber tips as in step 4, burnt the end of cf pieces with a lighter and then frayed out all the strands and shrink wrapped them to the ends of the HV pins. <br> <br>Should probably upgrade the original doc.
Another option for the discharge electrode is to use a piece of recycled old bicycle brake cable. Trim it or sharpen it so the wire ends are sharper, then fray the end by untwisting the strands. Multi strand copper wire where the strands are very thin, like hair-like, may also work.
WARNING! Devices like this have produced O3 aka Ozone. This has shown to aggravate breathing conditions like asthma. DO NOT repeat DO NOT use ionic cleaners if you or someone in the residence has breathing conditions. Further there is some risk of developing breathing conditions including but not limited to lung cancer. http://www.epa.gov/iaq/pubs/ozonegen.html
To reduce ozone production use less stages for lower output voltage, commercial air ionisers use 11 stages (= 22 caps half wave or 33 caps full wave), partly for this reason (and also to cut cost).

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