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Build a Variable High Voltage Power Supplyby burningsuntech on October 27, 2007

Table of Contents

intro:   Build a Variable High Voltage Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

step 1:   Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

step 2:   Gather the parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

step 3:   Lay out the chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

step 4:   Wire the low voltage side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

step 5:   Complete the build . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

step 6:   Power UP and Test it . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

step 7:   Safety Rules, and Disclaimer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

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http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

intro:  Build a Variable High Voltage Power SupplyI needed a variable 0 to 50KV high voltage power supply for my high voltage experiments that wouldn't break the bank, so I built my own.

With just a few parts from old microwave ovens, TV sets, and an oil burner, you can build an affordable instrument for whatever you wish to snap,crackle, or pop!

The key component is the voltage multiplier, which I covered in the High Voltage Multiplier instructable. Build it first, then drop it into this project for a variable output.

Image Notes1. Input Voltage Adjustment which varies the output voltage from 0 to 50 Kv in(100) 500volt steps.2. This is the feedthru insulator and the stud in the middle is the output.3. The case is an old Texas Instruments TI99 computer box. Any metal casewill do.4. HV ON pushbutton and indicator.5. Power Switch and READY indicator.6. Removable top cover for easy maintenance

Image Notes1. This test was at 25,000 Volts or 50 percent setting on my supply. The brightblue white spark is evidence of high current and lots of ultraviolet rays.

step 1: Theory of OperationThe diagram shows the supply in the de-energized condition and the case open.

Mains voltage is applied to the power supply thru a 120 VAC Panel connector. With the case closed, current passes through a 5 Amp fuse, F1 and through the casesafety switch, S1 causing the Ready indicator, I1 to light when the power switch S2 is placed in the ON position to energize the supply.

At this time, the power supply is NOT ON but in a state of readiness to enegize the high voltage stage.

When pushbutton S3 is pressed, relay K1 energizes and remains energized after S3 is released.

Current passes through Variac, VT1 which adjusts the input voltage to the OBT. The OBT steps up the input voltage to a maximum of 6,000 VAC. The output of the OBTis fed to the high voltage multiplier, HVM where it is multiplied to 51,000 VDC output.

To de-energize the supply, place S2 in the OFF position. K1 will de-energize and remove power from the OBT and HVM and all indicators will extinguish.

The case safety switch and the power contactor are not necessary for this supply to work. I thought the ability to power on and off by using a pushbutton was cool. Thatsall. The second schematic shows them removed.

Image Notes

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

1. 0 to 120 VAC variable output.2. 0 to 6,000 VAC3. 0 to 51,000 VDC output.

step 2: Gather the partsAll the parts with the exception of the variac used for voltage control came from my junk collection or Ebay. Here's the list:

CHASSIS - Texas Instruments TI99 Computer case. Any metal box will do as long as there is enough room for the parts. An electrical box will do just fine. The computercase had a switch, an AC plug adaptor, and a removable lid so it was perfect.

F1 - 5 Amp fuse with holder (Radio Shack).

HVM - HV Multiplier - This is a build it yourself part made up of (6) 12KV High Voltage Diodes and (6) 470 picofarad 20KV High Voltage ceramic doorknob capacitors.You can buy all the parts on Ebay. I have already posted an instructable on this. Just search for High Voltage Multiplier.

I1 - READY Indicator - GREEN 120 volt Neon lamp (Radio Shack). An old 120 volt Neon indicator from a microwave oven is what I used here.

I2 - HV ON Indicator - RED 120 volt Neon lamp (Radio Shack).

K1 - Contactor - 120VAC 10 Amp DPST Relay with a 120VAC coil.

OBT - Oil Burner Transformer salvaged from an old oil burner from a mobile home rated at 120VAC @ 2.25 Amps on the input and 6Kv 20Ma on the output. The singlepole type was used here. This can be purchased from a burner service company for about $65.00

S1 - SPST N.O. Cherry Microswitch for case safety.S2 - DPST Toggle or rocker switch for power on.S3 - SPST N.O. 120VAC Pushbutton switch.

VT1 - A variac was purchased for $60 from an electrical supply house. Any dimmer that can handle inductive loads up to 5 amps will work. The variac can control 2.5amps. Just enough for the OBT.

MISC - You will need some wire lugs and various colors of wire scavenged from power cords for the internal wiring.

Image Notes1. Case Safety Switch used to cut power when the case is opened.2. AC Power Adaptor also has a fuse holder built in. If yours doesn't, you will need to add a 5 amp fuse with a holder to the list3. Power Contactor or Relay for controlling the HV Circuit.4. Variac for input voltage control.5. Oil Burner Transformer produces 6000 volts AC at 20 Milliamps for the multiplier on right6. Multiplier for raising the 6000 volts to 50,000 volts at the same current.7. High Voltage Start switch with indicator.8. Power switch and indicator9. Added back panel

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

step 3: Lay out the chassisIf your box has stuff in it, gut it. Take everything out of it except essential parts. I kept the power switch and the AC Adaptor. Everything else, GONE!

If your box has HANDSIZED holes in it, patch em. You don't want little ones (or a nosey neighbor) sticking their paw in the box with power on. Mine needed a cover forthe back and a new face plate made of sheet aluminum. It would have cost me less to just use an electrical box instead.

Next, layout all the parts in the approximate locations shown giving yourself plenty of room for wiring. Space is essential in this project because we want to limit thepossibility of arcing between high voltage components.

Drill holes where needed for mounting the parts and secure your parts using whatever hardware you have for working with sheet metal.

Image Notes1. Case Safety Switch used to cut power when the case is opened.2. AC Power Adaptor also has a fuse holder built in. If yours doesn't, you will need to add a 5 amp fuse with a holder to the list3. Power Contactor or Relay for controlling the HV Circuit.4. Variac for input voltage control.5. Oil Burner Transformer produces 6000 volts AC at 20 Milliamps for the multiplier on right6. Multiplier for raising the 6000 volts to 50,000 volts at the same current.7. High Voltage Start switch with indicator.8. Power switch and indicator9. Added back panel

step 4: Wire the low voltage sideDecide if you are going to include a power contactor and case safety switch. If so, use the first schematic. If not, then use the second schematic.

Wire the supply starting with the AC connector, fuse holder, switches, variac and power contactor.

Test each stage of your build to make sure your wiring is correct.

Next wire up the OBT and test the range of the variac.

To test the output of the OBT, hold a GROUNDED screwdriver near the OBT output terminal.

If you see an arc, good. Power off the supply and disconnect it from Mains and move to the next step.

Image Notes

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

1. 0 to 120 VAC variable output.2. 0 to 6,000 VAC3. 0 to 51,000 VDC output.

step 5: Complete the buildDepending on how you built your multiplier, you need to mount it to the chassis so it doesn't move around. In my case, I made a pair of homemade U shaped woodenmounts and glued the multiplier to the mounts using contact cement.

When dry, mount the multiplier in the chassis and wire it to the OBT and ground.

For the output, I passed the 50KV lead through the chassis using a 2 inch large rubber stopper as a grommet and some corona dope to prevent arcing. This worked until Ipassed the 35KV mark and then it arced over.

So I bought a screw on PVC plug and passed a 2 inch brass screw through the center, then filled it with 30 minute epoxy and let it cure.

I secured the feed through to the chassis with a piece of threaded PVC pipe to match. I then cut my 50KV lead to length and soldered it to the screw head on the back ofmy feed through.

I coated the whole assembly with corona dope, let it dry, and tried again. This time I succeeded and got to the 50KV mark at 100 percent without any arcing

Image Notes1. Input Voltage Adjustment which varies the output voltage from 0 to 50 Kv in(100) 500volt steps.2. This is the feedthru insulator and the stud in the middle is the output.3. The case is an old Texas Instruments TI99 computer box. Any metal casewill do.4. HV ON pushbutton and indicator.5. Power Switch and READY indicator.6. Removable top cover for easy maintenance

Image Notes1. This test was at 25,000 Volts or 50 percent setting on my supply. The brightblue white spark is evidence of high current and lots of ultraviolet rays.

step 6: Power UP and Test it*** WARNING ***THESE NEXT STEPS ARE DANGEROUS.

Connect the power to the supply and turn on the main power switch. The "Ready" Indicator should light.

Set the voltage to 50 percent and press the HV ON pushbutton.

The HV ON Indicator will light and you will hear a slight hissing sound. This is okay. If you hear any snaps or arcing, determine where the problem is, shut off the supply,and dope the area. When it dries, test again.

With a grounded screw driver, bring the tip of the screw driver in close proximity to the output stud and watch for sparks.

*** WARNING ***DO NOT TOUCH THE OUTPUT STUD WITH THE SCREWDRIVER. PERMANENT DAMAGE WILL RESULT.

If you are confident in your building skills, or hungry for sparks, SLOWLY ramp up the voltage to 100 percent and test again with the screwdriver.

Success will be indicated by the 2 inch long spark that you get from the supply.

*** WARNING ***DO NOT ATTEMPT TO MEASURE THE OUTPUT OF THIS DEVICE WITHOUT SPECIAL TEST EQUIPMENT OR THE PROPER SAFETY EQUIPMENT.

*** DANGER DANGER DANGER DANGER DANGER DANGER ***

THE CURRENT PRODUCED BY THIS SUPPLY ALONG WITH THE HIGH VOLTAGE MAKES THIS DEVICE DANGEROUSLY LETHAL! DO NOT TOUCH THE HIGH

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

VOLTAGE STUD DURING OPERATION. THIS THING WILL KILL YOU! GROUND THE STUD AFTER EACH SHUTDOWN TO DRAIN ANY REMAINING POTENTIAL.

Image Notes1. This test was at 25,000 Volts or 50 percent setting on my supply. The brightblue white spark is evidence of high current and lots of ultraviolet rays.

Image Notes1. Input Voltage Adjustment which varies the output voltage from 0 to 50 Kv in(100) 500volt steps.2. This is the feedthru insulator and the stud in the middle is the output.3. The case is an old Texas Instruments TI99 computer box. Any metal casewill do.4. HV ON pushbutton and indicator.5. Power Switch and READY indicator.6. Removable top cover for easy maintenance

step 7: Safety Rules, and DisclaimerSAFETY FIRST!

ALWAYS wear rubber safety gloves and stand on a rubber safety mat when operating this supply.

ALWAYS wear protective goggles when power is on. Especially if you plan to power a laser with this unit.

NEVER touch anything or device that is connected to the supply while it is in operation without adequate protection.

NEVER defeat the safety switch on the case or operate this supply with the lid removed.

DISCONNECT the supply from power before opening or working on it.

FOCUS your attention on what you are doing with this device. Eliminate any distractions or annoyances in the area where you use this device.

DO NOT ALLOW others to operate or work in the same area of this device without adequate supervision or safety training.

REMEMBER, Smokey says, only YOU can prevent People Fires!

*** DISCLAIMER ***You, the builder and user, bear the responsibility for your own safety in building, testing, and using this supply. By building this device, you acknowledge the risks involvedin it's operation and accept those risks as a result. I will in no way be held responsible for your actions, including your death by this instrument and you accept theseterms by building and using this device.

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

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Comments50 comments Add Comment view all 53 comments

 TheMadScientist says:  Aug 31, 2008. 9:41 AM  REPLYearlier somebody said this has the power to drive tesla coils. you need DC to drive a tesla coil. therefore, you cannot.

 burningsuntech says:  Aug 31, 2008. 1:15 PM  REPLYMad ScientistActually, You can drive a tesla coil with this device cause its output is pulsating DC and yes, it has the power to drive one.

As far as the Diodes are concerned, a check on Ebay revealed some serious diodes that would set you back a few hundred dollars if money is no object.A ten amp diode at 20Kv will set you back nearly $150 and you need six in this configuration. My only question would be where you going to get a caseand enough oil to drop THAT in?

Raving Apache

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

 TheMadScientist says:  Aug 31, 2008. 9:43 AM  REPLYlove the voltage multiplier btw. but you need some hardass diodes once you get further up the ladder. tell me where you find yours please. not microwavegunn's either.

 bombmaker2 says:  Jun 28, 2008. 7:06 AM  REPLYi cant find any dpst relays

 burningsuntech says:  Jun 28, 2008. 10:50 AM  REPLYI salvaged mine from an old dehumidifier but any relay will work if the contacts support 5 amps of current at 120 volts AC. Also look for them as'contactors'.

Raving Apache

 bombmaker2 says:  Jul 17, 2008. 6:32 PM  REPLYthanks

 Derinsleep says:  Jun 25, 2008. 1:52 PM  REPLYwill this work for lower voltages

 burningsuntech says:  Jun 27, 2008. 9:21 AM  REPLYDerinsleepThis will work for any AC voltage up to the maximum of the diodes, in this case 12000 volts.

 Derinsleep says:  Jun 27, 2008. 11:16 AM  REPLYthank you

 alexhalford says:  Apr 15, 2008. 11:09 AM  REPLYPresumably this would be perfect for a jacob's ladder or a telsa coil supply???Also could you use a flyback for the HV transformer?

 burningsuntech says:  Apr 16, 2008. 6:30 AM  REPLYalexhalfordThis definitely has the power to drive a jacobs ladder or a tesla coil. Just the OBT alone works as a nice jacobs ladder.

In this design, you cannot use a flyback without some form of step down from AC mains. Also, the flyback is designed to operate at 15.750 KHz whereasthis device runs at 60 Hz. You would need a circuit to produce the 15 KHz input.

The multiplier would work with a flyback, though. Many TV sets have these multipliers built into the flyback as they are.

raving apache

If you were using only the multiplier section of this device then

 alexhalford says:  Apr 16, 2008. 4:29 PM  REPLYOK thanks very much. BTW, do ignition coils powered by square wave pulsed DC generate high voltage AC or DC???

Thanks Again

Alex

 burningsuntech says:  Apr 17, 2008. 4:47 AM  REPLYAlexAC implies that in some way the output signal is positive then negative with respect to ground. DC implies that the output is either positive ornegative with respect to ground but does not alternate between the two.

With a square wave input from ground to positive and back, the output would be a pulsating DC high voltage.

Remember. Transformers of all types are AC or Pulsating DC devices. They cannot operate on pure DC.

raving apache

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

 alexhalford says:  Apr 17, 2008. 11:16 AM  REPLYThats what i thought... but in that case how is this setup appropriate:Above that diagram is written this text:This next circuit is designed for a higher powered output. Two ignition Coils are connected in parallel but with opposite polarity. This meansthat the output voltages of each coil are out of phase or opposite to each other (when one is positive, the other is negative). Using thisconfiguration the output is taken from the two coils output terminals, whereas the circuit above uses the output terminal and ground.

If the ignition coil is not AC and therefore never goes negative, how can the above be appropriate???

Thanks for all your help btw.

 burningsuntech says:  Apr 18, 2008. 5:28 PM  REPLYNote: AC is defined as the alternating input of a current between two values. The fact that the values may be +10KV and ground does notnegate the device as an alternating current device.

Most people think of AC as a current that varies above and below ground but AC can be any current that varies between two positivevalues or negative values or between a positive and a negative value. It all depends on what your point of reference is.

raving apache

 alexhalford says:  Apr 19, 2008. 3:51 AM  REPLYThanks very much it makes sense now.

Alex

 burningsuntech says:  Apr 18, 2008. 5:21 PM  REPLYAlexAll thats really happening here is the switching of the input to two coils, both of which are ISOLATED from ground. Therefore, their outputfloats above or below ground.

Believe me. If you touch one of the coil HV leads and ground, you're gonna get it!

The coils produce 10KV Pulsating DC out of phase from each other. Therefore, the voltage across the two HV leads is 20 KV. One leadwill be +10KV and the other will be - 10KV with respect to ground or 20 KV with respect to each other.

raving apache

 Ferrite says:  Feb 29, 2008. 6:53 PM  REPLYDoes the power supply supply a continuous voltage or just a single pulse? If it is continuous it would be good for a laser power supply.

 burningsuntech says:  Mar 1, 2008. 2:29 PM  REPLYFerrite

The output is pulsating DC and the reason I built it is to power a UV laser.

Don't worry about filtering but be sure to use a current limiting resistor in series with the laser tube or you will destroy the tube. To calculate the propervalue, use Ohms Law R = E / I

Good Luck and stay in touch. I would be interested to hear how you made out

raving apache

 bsibille says:  Apr 17, 2008. 1:48 PM  REPLYIf the diodes limit the current, what is the need for the resistor? Thanks!

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

 burningsuntech says:  Apr 17, 2008. 6:48 PM  REPLYThe diodes are 12 Kv PIV 550ma doides. They do not limit the current but they themselves cannot be used above 550ma. Since the supply is anopen ended supply, that is it has no built in load, a current limiting resistor is required on all devices connected to it that do not need 20ma (thetotal source surrent of this supply).

In other words. The supply will try to supply current all the way up to its short circuit point if you do not control the load with a limiting resistor.

raving apavhe

 Ferrite says:  Mar 1, 2008. 3:17 PM  REPLYThanks! I haven't built a laser yet, but plan to soon.

 agis68 says:  Apr 10, 2008. 3:10 AM  REPLYExcellent project, and very carefully done! Of course you can replace the VT1 with one of 220V for european countries.

 burningsuntech says:  Apr 10, 2008. 6:41 PM  REPLYThanks Agis

Any neon sign or oil burner transformer of either mains voltage will do as long as you follow proper wiring procedure and pay attention to the specs of allthe components.

Raving Apache

 agis68 says:  Apr 12, 2008. 3:23 PM  REPLYThanks again...i will try to make one and i will be in touch with you for any detail...

@gis

 bwana says:  Mar 9, 2008. 8:45 PM  REPLYcould the output of two neon transformers be connected in series? (to boost arc size for a jacobs ladder)

 burningsuntech says:  Mar 10, 2008. 6:41 AM  REPLYbwana

you cannot place two neon transformers in series as the output of the first would most certainly cause damage to the second.

Instead, why not just add more stages to the multiplier. It currently has 6.

Please see the link to the multiplier for more info on it.

raving apache

 alexhalford says:  Mar 29, 2008. 3:08 PM  REPLYAlso what current will this put out???

 alexhalford says:  Mar 29, 2008. 12:31 PM  REPLYhi could you use a neon sign transformer instead of an oil burner transformer???

 burningsuntech says:  Mar 29, 2008. 8:04 PM  REPLYalexYou can substitute a neon transformer for the OBT. The OBT was what I had on hand at the time. Both types of transformers have current limitingwindings in them. As designed, this device will source up to 20ma at 50Kv

raving apache

 sounder says:  Nov 18, 2007. 7:06 PM  REPLYCould an automobile ignition coil be used in place of the OBT? I know the ignition coil is an autotrans with a common point between pri. and sec. windingsbut the turns ratio is so much higher that the voltage multiplier wouldn't be necessary.

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

 burningsuntech says:  Nov 18, 2007. 8:21 PM  REPLYPerhaps. The two devices are similar but the Auto coil is a pulsed DC high voltage, low current device whereas the OBT is an AC high voltage, highcurrent device.

Ive attempted to drive an auto coil with 12 VAC only to find it getting hot and not able to produce the current I was looking for or the spark length Iwanted. If you decide to build one with an Auto coil, let me know how you make out.

 static says:  Mar 3, 2008. 10:33 PM  REPLYComparing an auto ignition coil operation to an AC transformer operation is comparing apples to oranges. While the ignition coil is constructed like anautotransformer, it's not a transformer per Se. DC flows through the ignition coil primary for enough time to create strong magnetic field. Current isproduced in the secondary when the current through the primary is turn off and the mgnetic field collapses. I suppose if an ignition coil was feed ACof a frequency near what coil sees when doing the job it was designed for it MAY operate as conventional AC transformer. Problem is that would beat least 800 Hz.

 membrane says:  Nov 18, 2007. 8:14 PM  REPLYAn NST or neon sign transformer could be used instead of the furnace transformer in a circuit like this and actually would work better then the OBT asNST are inductively current limited so they're less likely to self destruct if shorted.An automotive ignition coil would yield less milliamperes but higher voltage as some do operate at 50KV but you would need some sorta DC PWM circuitvs a variac as hooking 120v AC to a 12v coil would be a bad idea.

 burningsuntech says:  Nov 18, 2007. 8:23 PM  REPLYRoger that, membrane. NSTs do work well and would be a good choice. The OBT is what was onhand.

 Fro says:  Dec 2, 2007. 1:47 PM  REPLYSeems like a really great project and I might just build something similar, but I didn't really understand if the output is AC or DC. Also, in place of a variaccould you use a basic light dimmer since they're much cheaper, or does the fact that they chop up the sine waves cause problems?

 burningsuntech says:  Dec 2, 2007. 3:10 PM  REPLYHey FroThe output is pulsating DC or unfiltered DC.As for the dimmer, you can use one rated for inductive loads like motors and, in this case, transformers.Standard light dimmers are for resistive loads like incandescent lamps and would not work.The only exception would be to use a dimmer directly into the multiplier and leave out the OBT. Make the multiplier large enough and you could drive itdirectly from the AC line.BTW the output of the dimmer doesn't matter if noise on the output doesnt bother any circuits attached.Good luck.BST

 Fro says:  Dec 5, 2007. 1:32 PM  REPLYthanks

 littlechef37 says:  Nov 19, 2007. 10:07 PM  REPLYawesome man, nice instructable id love to make one but im not that resourceful and it would be a hazard!!!!!! in my hands any idea on how to make a smallerone for running motors and stuff ?

 burningsuntech says:  Nov 20, 2007. 1:53 PM  REPLYHey littlechef thanks for the compliment.Depends on what you are running. Any AC motor could be run from a device similar to this if you had a large enough Variac. This one is too small formost AC motors and is for lights only or in this case loads that draw no more than 2.5 amps.

Your best bet for AC motor control is a triac with a variable pot to control the speed

For DC motors you would need a special controller or a large Rheostat tha could handle the current.

Google some of the terms in my reply and find a circuit tha will do the job. BST

 littlechef37 says:  Nov 20, 2007. 7:19 PM  REPLYthanks

 bumsugger says:  Nov 18, 2007. 11:58 AM  REPLYNice one "burningsuntech" a very neat and accurate "build," great device!

http://www.instructables.com/id/Build-a-Variable-High-Voltage-Power-Supply/

 burningsuntech says:  Nov 18, 2007. 8:08 PM  REPLYThanks bumsugger. It took awhile to put together and document. Im looking to sharing more on this subject in the future.

 xrobevansx says:  Nov 17, 2007. 9:09 PM  REPLYThat case isn't *exactly* a TI99 4/A "case" so to speak. Isn;t it a Ti 99 4/A hard drive case?

 burningsuntech says:  Nov 18, 2007. 6:01 AM  REPLYYes it is. But who would remember that far back in computer history anyway. You and me maybe. Thanks for the clarification.

 membrane says:  Nov 18, 2007. 8:06 PM  REPLYLooks like the TI 99/4a PEB or peripheral expansion box it added 8 expansion slots to the 99/4a I actually own a functional example.

 xrobevansx says:  Nov 18, 2007. 6:52 AM  REPLY40 megs if I remember correctly. A POWERHOUSE!!!!

 !Andrew_Modder! says:  Nov 17, 2007. 6:51 PM  REPLYomfg! that is crazy man! That is really awesome, but honestly i cant think of anything that would be able to run up to 50,000 volts :-P! Hey, also couldnt youmake plasma, or a tesla coil with that, cause its really f'ing high voltage :-)?...1st

 membrane says:  Nov 18, 2007. 1:16 PM  REPLYAn adjustable HV psu in this range also is useful for powering those antigravity lifters or a Marx HV pulse generator.

 burningsuntech says:  Nov 18, 2007. 6:04 AM  REPLYWell, not just high voltage stuff. im planning a laser project and need to adjust the voltage for tuning.

Conceivably, you could build a large enough stack in the multiplier to get to 500,000 volts or more but it is very costly. Thx

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