Ward's Build of Bob Boyce's TPU

[HumblePie]

@All,
Well I had this battery HVPS rock solid yesterday at 210V @ 23mA after testing many inductor candidates,  Some really pulled too much power while making hundreds of volts.  This one was the winner for low Amps / high Volts / no heat from load.  After wire wrapping and with fixed components to ensure repeatable results, I am getting only 80V with same frequency & duty-cycle, though I added 555 decouple not there before.  What a disappointment.  I will get back to at least 200VDC somehow... with 1 9V battery like before.   

Edit:  Nixxing the 220uF decouple brings output to 88 VDC.  I replay these words: 'do everything the exact opposite of what you have been taught'.  And SM's words about: 'PCB materials adsorbing moisture' and 'soldering at least 1/2" above the PCB material'.  I thought Wire Wrap would benefit from not having pads and traces stuck to the board.  I will test to see if it is the Vector Board or this 30 AWG causing the difference in output. 
If it is either, I should expect the same RE sapping to occur driving the Primaries with similar Ckt materials.  I may have to wire without these particular materials.  I will try IRF840 also and Flyback XFRMR I found.  For Flyback, do not miss this info about Line powered HV PS:   http://jnaudin.free.fr/lifters/labhvps/index.htm   The link contains info on how to learn the pin-out for any Flyback... and I see the high impededance may make this an ideal Choke.  End Edit -

I left the PWM out because the duty cycle yields max out as is and I won't be needing less until I can make more than 200VDC to start with. 

Hopefully I will learn how to achieve 1 or 2 KV+ as Jason has done before.  Any tips Jason?  This is Eldarion's same ckt he posted except the 10K Gate resistor to Gnd (less decreases output / eats power)... and the 220uF 35V 555 decouple Cap.

I need a shield for the controller.  I chose the center two segments to be 4X because the Secondary makes these resonate at higher freq'.

Ward

[HumblePie]

@All,

I will start explaining more because some tell me they still do not fully understand what to do.  We all know how that feels, so... 

I still have not put the fixed HVPS back onto Bread Board yet to see if I could get 80V back to 225VDC.  I will; later.  I need to start somewhere and the Vector Board provides support I must have so I proceed with it.  If this fiberglass affects the circuit, I will seek out PTFE Eyelets if they are available, else work something else out.

That large Capacitor was a saftey hazard.  I found a very small 1.5uF Film Cap' rated for 1000VDC.  Nice thing is is bleeds itself off in about 2 seconds... that 80uF at 400VDC discharged like a fire cracker if no resistor used.  I abandoned fixed frequency and pulse width HVPS that Eldarion shared and substituted an IRF840 for the '640 and a corrected 556 PWM from Bob's PWM3f schematic.  PWM3f schematic is missing 10K resistor from the 556 Timer Pin 8 to +V for the 'negative edge trigger' Ckt which now works.  Oh ya, you must decouple the 556 with a Cap' else PWM stops triggerring if > 6V supply.  I used 100uF 35V Electrolytic.   I selected the 556 PWM because the 556 can drive a FET well.  The PWM on time can not be smaller that 556 Async CLK's off time.   The .001uF Cap is about fastest / smallest possible without failing to hold the Trigger long enough.  It yields an 8uS on time minimun from the PWM.  The pulse width can be raised so that off-time approaches 1uS.  I learned to always start with lowest frequency and shortest PWM pulse, else it gets wierd tuning it... try it and you will understand what happens when the frequency's period becomes less than the PWM on-time.   This is a great first PWM project.  I recommend it to anyone scared of any of the electronics.  It is not so hard after all.  I used jumper to select Range Cap.  Don't bother.  Just use a 103 / .01uF ceramic since all the power you desire lies just above audio range... not higher.

Most interesting I thing I saw tuning the frequency and pulse width was that when I set the pulse width at 8uS minimum and lowered frequency, I can see ramp wave graph shape of the Vout data. 
Near max frequency of 100KHz, I found that tuning pulse width for max V out accross the 1.5uF 1000V storage Capacitor was twice as efficient if I did so at a frequency where the V out was minimum when pulse width was minimum.
Near min frequency it did not matter where I set PW for max V out.
I found max V out happens at minimum frequency... and it is audible and 'annoying'.  I get 500V out with ringing, 400V out if I raise frequency to 15KHz.
Power consumption with inductor removed is 25mA.  With inductor and 400VDC out it is only 22mA... I don't know why.  At 15KHz, getting 500 V out uses 75mA, so I settle for 400.  9V battery discharge info here:  http://www.powerstream.com/9V-Alkaline-tests.htm

I hear one may place a Bridge Rectifier AC inputs accross the inductor and feed the + & - Bridge out's back to battery... the best way to extend battery life.  I will try that when I get more Vector Board.

I had troubles with an alternative 555/Op-Amp PWM for some reason I have not solved.  I posted example of switching problem I see using LM193 PWM here:  http://www.rmcybernetics.com/projects/DIY_Devices/homemade_signal_generator2.htm?showPruned=1

Lastly, the highly accurate PWM's seen on the web using diodes to isolate charge path from discharge path are for fixed frequency PWM only... so that one is out.

I have a short somewhere on my GAL card and will fix is ASAP.  I think I can try starting up 3 Prim's.   I ponder an inverting Op-Amp on Pancake Collector as avalanche shutdown trigger.  This is only way until my Gammahighvoltage.com SM-10 HVPS arrives Dec 1st.  I deisire it for its 0 to +5V linear HVPS control.


BTW - I have not forgotten RichSAS's wet cell battery bank as HVPS (or as the entire load), I just can't afford that many batteries or store them near my bench just yet... ( I want lots of available potential) so I strive to force the LEM towards the load.  Then I can test using one battery to be charged and increase batteries until impedence stops all the action.  I will test Earl's recommended 22 MOhms with and without the choke.
Ward

[MarkSnoswell]

Hi Ward,
   I dont know how many people are watching this. Great work and dedication.

Mark.

[Bruce_TPU]

Hi Ward,
   I dont know how many people are wathing this. Great work and dedication.

Mark.

I agree Ward with Mark's comment, totally.  Also thank you for the outstanding documentation of your last post.  I look forward to when you are testing the coil.

Great Job!   

Bruce

[HumblePie]

@All,

Well the status is my on-board Op-Amp oscillator has jitter.  I used 20% Cap's.  In the 12X CLK it is hard to see.  In the divided down frequencies it is quite apparent as stationary trace left side of 'Scope, shakes at right side of Scope display.  My DDS 20 as external CLK is solid, healing troubles with all but 1 channel (from GAL even with HexFET's removed) will figure out tomorrow.

I know at least two who read this (or one now?) and feel I am somehow way ahead of them... and who tell me they only comprehend part of what I write (e-mail that is) and say and ask them to read.  I thought I was the only one feeling this way.  I add detail for them.  Each is the absolute cream of the crop best at what they do for a living and it is very technical stuff I assure you, but these new and unusual technical realms are not so easily digested if taken in without hands on or too much at once.  I am just an ordinary average mind amoungst here PHD's, with and without sheep skins, so I know the feeling.  So many difficult choices that a nap or cleaning the garage becomes easier than progressing forwards with this.  I know well.  It does not matter if only these two benefit from this.  I am going to drag them along with me... unless they stop trying (putting tangable things together).

New folks, use a spiral notebook and record everything every day.  What you read, where, which files were there, what you did, conclusions, follow-ups, to do, to buy, to study.  I can not believe intellegent and capable people are trying to learn these topics from memory alone.  Take notes.

Thank you Eldarion and everyone else here leading the way.  Everyone needs to start somewhere and without your lead I was not so confident with all the choices.  I tried to wait until I understood more before trying anything so I would choose only the best known methods and came to understand this is the only way to fail. 

If I hadn't built the stripped down HVPS I would have missed the finer points of Bob's 556 PWM and not figured out the missing resistor (I finally read the right place about it on web).  Previously, I had convinced myself that Bob did switcharoo with usual R1 & R2 ratios and put that Cap' there to test our ability to figure it out... and at first I failed to understand it was supposed to have very high duty-cycle CLK so that at least would stay constant through freq' range to better serve the negaive-edge trigger shceme.  I switched his Resistor ratios and tossed the Neg edge trigger Cap thinking it was a blocking Cap placed there to mess up the lazy minded.  I did indeed ask everyone in the group who would discuss it and searched the web for Bob's pure 556 PWM and still never found it.  I only found the negative edge detect example when I turned away from Op-Amp PWM again and really wanted Bob's to work... via will-power.

It is a shame that of dozens of capable people I know on this Earth I can find only two willing to participate in this with me.  The rest will never know. Never from me that is. The few who would rather wait for me to learn it and just tell them remind me of those waiting for Bob to hand them a working Hex Controller.  What a shame... for their own loss.  This is like a 'Pot-Luck Dinner'.  Everyone should try to bring something to the party... something different.  I hope someone posts details of their LC delay scheme soon because I think I might need it .)

Ward