Why you not answer PM? am I troll for saying your name on here? I try drive fb with esu but not much with all 300w why so? I know not rem because jumped if you say how rebuild fb that's lovely I say sincere to you but if you believe is out of my hand you know right that I play with the stupid typed accent all for fun but wouldn't waste your time because that selfish mean not funny I say will you be patient with me cause it is not that easy for me to think about always Thank for saying friend to me! I am friend to you too
I did fix email like you say to you right about radionecks site not like opayq emails plz reply so know we are ok?

 

Hey, Aleph --- No worries! I'll try to respond here tonight/early Wed AM --- For now please see your PM...

Best regards
HP

 

Ok -- inasmuch as this is your thread I'll briefly respond to some of your off-topic inquiries/comments --- Please be advised, however, that such discussion is appropriately confined to the OT forum or, better yet, PM/Email ...K?

am I troll for saying your name on here?

No, not quite! -- Actually AAC is pleasantly unique in that, in my experience (to date), it appears to be 100% troll free! -- (FWIW I regard a troll as a poster who deliberately and maliciously wastes other participants time and/or creates 'ruckuses' merely for 'sh_ _s and giggles') --- That said, I'm bound to say that attempted 'mining' and publication of information contrary to the wishes its 'proprietor' is 'bad form' at best --- Were I angry with you, I assure you, I'd leave no room for equivocation!

plz reply so know we are ok

Your use of the pronoun 'we' in that context gives me 'chills' on a number of levels -- Most prominently; Having been twice accused of 'sock puppetry' let's not further complicate matters via inciting suspicion/allegations of 'Sybil-ism'

I say will you be patient with me cause it is not that easy for me to think about always

I'm not sure I 'follow' your meaning? -- If you're saying my level of formality 'gets on your nerves' - Sorry! Such is my genuine, long accustomed mode of textual communication. While I am sincerely delighted to patiently guide you through these subjects/projects I refuse to 'talk down' to anyone! -- Said sentiment goes double in your case inasmuch I have no desire to perpetuate the 'classic' misconception of our (shared) demographic as 'intellectual lightweights' Capiche?

Know also that I'm always open to requests for further detail or rephrasing of statements...

I say sincere to you but if you believe is out of my hand

FYI -- My dubiety as regards your sincerity stems from your predilection for topics known to have special interest to/involvement with myself (while being otherwise peripheral subjects on these fora) -- Thus, at risk of appearing narcissistic, I am given to suspect your motivation is geared more toward eliciting my interaction than to genuine interest in said topics ---- That said: if it is your assertion that, whatever your initial motivation, you've been 'bitten by the bug', as it were -- that's good enough for me!

Ok! To your on-topic content:

I try drive fb with esu but not much with all 300w why so?

Short answer: Excessive frequency --- 'Plain vanilla' 'Bovies' generally operate in the 500kHz 'area' --- said frequency being an order of magnitude higher than optimal for the geometry/core material 'combination' comprising TV LOPTs --- That said such instruments function effectively as air-core xfmr 'drivers' - should you wish to experiment with this best results are obtained via selection 'pure cut' (i.e. CW) operation then 'walking' the power up while observing transformer output -- For all that, it is my assertion that, for these purposes, you are better-served via topologies incorporating the transformer (and hence the load) as a frequency determining element of a power oscillator...

Looking forward to further on-topic discussion!

Best regards
HP

 

You said

I refuse to 'talk down' to anyone! -- Said sentiment goes double in your case inasmuch I have no desire to perpetuate the 'classic' misconception of our (shared) demographic as 'intellectual light weights' Capiche?

That means you Polish too? Ha ha! Not asking to dumbdown only patience all that needed
What you said about sincerely interested I know because I interested in all that too. Always afraid of isotopes because permanent but x-ray like demanded gamma source very good I only say we mean like we good want know not cross with me! Thank you for saying about esu frequency! Plz tell me steps for improve transformer to the larger hv and about fkp and mkp dielectric same but not so electrodes? I'm sorry about guessing at who you are like I say in pm conversation will have aecic soon so I can send number

 

@Aleph(0)

Plz tell me steps for improve transformer to the larger hv

Good deal! -- Give me a couple days to get 'round to composition of a clear, 'linear', procedure - After all one missed or misplaced step=one less EHT winding!!!

...and about fkp and mkp dielectric same but not so electrodes?

Yes, that's essentially correct - MKP denotes metalized polypropylene dielectric film construction whereas FKP denotes similar construction but with the addition of foil electrodes -- note, however, that whereas FKP_1 is essentially MKP_10 'plus' foil electrodes -- FKP_4 sacrifices bilaterally metalized dielectric for unilateral vacuum deposition (thus maintaining marginal 'self healing' properties) --- If you find this annoyingly convoluted, rest assured you are not alone! --- While I have found WIMA products to be both quite satisfactory and highly reliable - there remains definite room for improvement on the product nomenclature 'front' -- à la Intel's 'course' following introduction of the 'Pentium' CPU series...

As a practical matter WIMA pulse App PP caps (in order of ascending 'pulse duty') are: MKP_10, FKP_4 and FKP_1

Note: MKP_10 is sufficient for the application in question...

will have aecic soon so I can send number

Again, no rush! It'll probably take me a while to 'run down' the instruction/data sheet anyway!

That means you Polish too? Ha ha!

Oh! You're a riot!!!

Best regards
HP

PS -- Hey, everyone! -- Any comments and, especially, corrections are more than welcome!

 

@Aleph(0)

Thought you might find these useful...

http://www.wima.com/EN/applicguide.htm
http://www.wima.com/EN/pulseselection.htm
http://www.wima.de/EN/products_pulse.htm

Best regards
HP

 

You said

PS -- Hey, everyone! -- Any comments and, especially, corrections are more than welcome!

Why you for outsourcing help? You afraid you not knowing totally everything? That ok cause you let me act stupid so I let you act smart Thank you for saying and pages about resonance capacitor so I can do right first time Should it be resonant royer or zvs for best hv? I think know demographic you mean but you set me up Polish joke other friends think I'm funny I hope you like me I really so happy to learning

 

@Aleph(0)
For reasons I'll explain via PM I'm going to request that this thread is relocated to the OT forum -- as the thread starter your input will likely be required - so please watch for my PM -- If you agree please PM the moderator (or post a message here) to that effect -- Thanks!

PS -- I'll reply to post #27 following disposition of this 'thread location' matter

 

@Aleph(0)

UPDATE:
FYI -- I have PMed a member of the moderation staff as per the above post (#28) -- I have included you as a party to the conversation so... Please watch your PM

TTFN
HP

 

HP I post on private thread to say I agree that like move too! Moderator not there yet so I wait?

 

HP I post on private thread to say I agree that like move too! Moderator not there yet so I wait?

It's a done deal ---Many, many thanks for you're cooperation!

Best regards
HP

 

As promised an (embarrassingly verbose and less than eloquent) response to post #27

Should it be resonant royer or zvs for best hv?

As an aside: Be advised that description of the 'Mazzilli' power oscillator as a ZVS implementation is a common misnomer. Said circuit is, in essence, a modified resonant Royer specially designed for 'analog' (which is not necessarily to say linear) operation of power MOSFETS. --- The Mazzilli's popularity owes to the relatively high current availability attendant thereto -- unfortunately typical EMF attainment leaves much to be desired - As an illustration of this you've merely to view YouTube videos of (so called) "ZVS" operation -- notice that the strike distance is often less than 1 cm... So constructed the Mazzilli oscillator is little more than a low duty-cycle 'solid state MOT' -- To wit: High current but disappointingly low OC EMF... --- That said, inasmuch as the proposed PSU requires only 20KV peak (each transformer), the Mazzilli topology (with a downward adjustment of the resonance cap) may serve as an effective, high current driver for your purposes.

Far and away the best choice is a driver implementing a current-mode PWM controller (e.g. UC3844) based design... Inasmuch as said circuit switches at a pre-settable primary current level, the optimal frequency may be chosen without regard to under/over 'charging' of the core... FWIW certain DST units may be successfully operated via said scheme to upwards of 80kV -- such being possible owing to the "EMF asymmetry" of the drive waveform -- hence limiting the 'reverse stress' upon the rectifiers...

Here's a link to a YouTube video demonstrative of this --- Note that the presenter is slowly increasing the primary current 'switch off' setting --- maximum strike distance (seen at ~ 0:35) is consistent with an output EMF of between 80kV - 120kV

Demonstration of a Current Mode PWM Driver

Please note: I include the above solely as a demonstration of the efficacy of IM PWM drivers! Incorporation of DSTs in serious EHT PSU designs is not recommended inasmuch as their reliability in such operation is unpredictable (even among transformers of the same lot) and, in all cases, unreliable!

But to answer your question:
For the purposes at hand I suggest you initially try a 'Mazilli' driver -- if you can achieve the required EMF via reduction of the resonant cap (i.e. increase of the resonant frequency to ca 50Khz) good enough! -- otherwise the I-mode PWM driver will work perfectly -- too good, in fact, if you're not careful! (but with the caveat that, owing to the afore noted asymmetry, cascade techniques will be, FAIAP, inapplicable) Remember stock 'tyre' wound secondaries should not exceed 25KV (peak) whereas 'rebuilt' units may be safely operated no higher than 50kV --- The advantage of the 'tyre' style EHT winding being greatly increased power-handling and improved reliability...

OBTW -- I haven't forgotten my promise of 'rebuild instructions'

So... to the 'idle chit chat'

You said
Why you for outsourcing help?

In this context, multiple heads are better than one!

You afraid you not knowing totally everything?

No! I'm afraid of knowing exactly nothing

That ok cause you let me act stupid so I let you act smart

Sounds like a deal! -- and a bargain at that!

...other friends think I'm funny

Of that I've not the least doubt

I hope you like me I really so happy to learning

Indeed I do! -- And ditto!

Best regards
HP

 

Thanks for all you are saying YT not play on page but can in ff browser so view I like very nice! You say cascade not work with pwm of old ac fb because asymmetric output from fb? Do I understand that ok cause 20kvpk is 40kvpp so like shift the minus 20kv to ov so output like 40kv pulsing dc? Very nice because like already rectified! capacitors wanted only for the filtering? Plz say about the rebuilding not before convenience of you I very happy about all this

 

@Aleph(0)

Re: the step-by-step LOPT optimization "tutorial" -- Please let me know what degree of scope/detail you require?

Best regards
HP

 

Excuse me, please.
Did you see this one?
http://forum.allaboutcircuits.com/threads/1-microfarad-20000-volt-dry-film-capacitor.113879/

I thought you might be able to help. I also thought you might have overlooked the post.
Just trying to be helpful.

 

HP Just the steps of the remove and replace center ok? #12 thats 200J capacitor! You have count fingers if pick it up charged She post links for site sell big hv capacitors somewhere on thread

 

@#12

Thanks for visiting our little jot of paradise!

Excuse me, please.
Did you see this one?
http://forum.allaboutcircuits.com/threads/1-microfarad-20000-volt-dry-film-capacitor.113879/

I thought you might be able to help. I also thought you might have overlooked the post.
Just trying to be helpful.

Anxon Manufactures an MKP of that value:
http://www.alibaba.com/product-detail/High-Voltage-Pulse-Capacitor-20KV-1uF_60195842791.html

Best regards
HP

 

You say cascade not work with pwm of old ac fb because asymmetric output from fb

Correct - The 'doubler' output EMF is equal to the sum of the absolute values of the positive and negative peak input signal excursions... Hence the smaller 'inverse' excursion 'term' will not significantly increase the cascade's output potential...

Do I understand that ok cause 20kvpk is 40kvpp so like shift the minus 20kv to ov so output like 40kv pulsing dc?

In principle, yes -- but with the following caveats:

1) The asymmetrically will not be absolute (i.e. some portion of the P-P output EMF will be on the 'wrong' side of ground)... --- Please pardon the informality
2) Produced as described (via PWM controlled primary current) the waveform will not be sinusoidal but, rather, a train of pulses of fixed frequency but indeterminate duty cycle...

Very nice because like already rectified!

As per caveat "1" above, not totally -- it is, however, quite advantageous in that most of the P-P output potential may be obtained with minimal loss of power via a single rectifier exhibiting a Piv consistent with only twice the inverse excursion of the output signal -- Although certain applications may dispense with rectifiers altogether, it should be noted that, for obvious reasons, the losses attendant to such designs will be twice those of the rectified arrangement...

If, at this point, you find yourself asking how a half-wave rectifier can be efficient -- I offer this: The 'half' of the wave passed by the diode is, in actuality, most of the wave! Get it? Polarity as a delineator of moiety applies only to polarity-symmetrical phenomena...

As regards your intimation that there will be no additional stress on the winding inasmuch as the potential difference is not increased but merely 'translated' --- again, correct in principle! Note, however, that the potential between ground and every point on the winding has increased twofold -- an especially critical area in this regard is the approach of the outer aspect of the 'tyre' to the core...

capacitors wanted only for the filtering?

Correct, as stated elsewhere, applied to this topology, cascades are neither useful nor required... --- At the frequencies involved (Ca. 50 kHz) satisfactory filtration is readily achievable with modest capacitances...

HP Just the steps of the remove and replace center ok?

Good deal! 'Tis in the works!

Best regards
HP

 

@Aleph(0)

As Re: LOPT rebuild procedure: --- Inasmuch as unexpected 'snags' are inevitable let's do this in 'installments' ...K?

OBTW: I won't have an excess of 'leasure time' prior to Tuesday -- So there's no need to perceive dilatory responses as 'slights' --- I plan to get straight down to this Tuesday or Wednesday --- In the meantime please assemble the materials/tools listed below and advise me of any problems/issues (via posts here)...

Best regards
HP

Materials:
Note: I apologize should you find my mixing of Std & SI units annoying -- Items are listed as sold in my region and, probably, yours as well (assuming my 'between-the-lines' reading skills are up to par)

Dimensions are not critical -- if in doubt please inquire!

1) 'Tyre-style' LOPT dissembled as per post #4 of this thread
1) 0.75"(ID) (nominal) * 8"(Len) CPVC Tubing
1) 1.25"(OD) * 2.5"(Hgt) Polypropylene Pharmaceutical vial
1) 90 ml tube of electronics grade RTV silicone adhesive/sealant (Important: Verify EG 'status' by noting presence of a silane -- as opposed to an acetic acid, odour in the uncured product!)
4) 0.75"(ID) *4"(Len) (Initial Dimensions) heat-shrink tubes
1) 60ml vial of 'HV' lacquer (a.k.a. 'Corona Dope', etc...)
1) 3mm(Dia) * 120mm(Len) section of threaded stock complete with 4 burs
-Solder(Non-ROHS!), soldering 'wick', etc

Tools:
-scalpel
-Hemostat
**Note: If you do not have ready access to surgical instruments, 'equivalent' tools may be substituted, they must, however, be in good condition!
-Standard Pliers
-small locking pliers
-Needle nose pliers
-Precision screw/nut drivers, etc...
-'Ignition point' file or 300+ 'grit' emery cloth/paper
-Soldering tools
-Heat gun
-VOM, 'Mini-clip' Jumpers, etc...

 

Plz be patient I getting better quote parts of post You said

As per caveat "1" above, not totally -- it is, however, quite advantageous in that most of the P-P output potential may be obtained with minimal loss of power via a single rectifier exhibiting a Piv consistent with only twice the inverse excursion of the output signal

I understand twice for symmetrical with shunting capacitor but wouldn't now be sum |forward| plus |reverse| cause need to check charge on capacitor? Sorry that I dumb
you said

As regards your intimation that there will be no additional stress on the winding inasmuch as the potential

You say my _intimation_ so saying about my love life now? Joke
You said

ml tube of electronics grade RTV silicone adhesive/sealant (Important: Verify EG 'status' by noting presence of a silane -- as opposed to an acetic acid, odour in the uncured produ

What silane odor? you mean saline? I having most the tools I'll be shopping for all list not have tell you if not find something I not be slighted when you not posting just worried I said wrong thing and you cross also worry that fate catch you or like that