Good advices for a newbie (threading tools lathe)

[rendoman]

Hi
I want to make some changes in power supply, I'm thinking that can be more helpful tuning coils and circuit with final voltage, and not with the reduced one.
I tried a voltage doubler with 4x400v capacitor in series, an huge waste of capacitance, but my only way to use a doubler up to kv. Voltage without load is 1016 volt now, with load connected I think i'm in datasheet manual of tube. Hope it will give me some good results in flame stability and autofire.
keep fingers crossed for me!

[PJs]

Food for thought...website:

"The Cockcroft-Walton multiplier serves as a more efficient high voltage source for photomultiplier tubes requiring up to 2000 V. [ABR] Moreover, the tube has numerous dynodes, terminals requiring connection to the lower voltage “even numbered” nodes. The series string of multiplier taps replaces a heat generating resistive voltage divider of previous designs.

An AC line operated Cockcroft-Walton multiplier provides high voltage to “ion generators” for neutralizing electrostatic charge and for air purifiers."


Used them a few times back in the day a few times. Just keep in mind the ratings of the components and that each successive stage is less efficient.

Did you get your test equipment? Thanks for the update! ~PJ

[rendoman]

Thanks for the link! Very nice with graphs and info
Yeah I got only the Lc meter, frequency counter is still on the mule's back It takes really a lot of time to shipping with normal post from china... i buyed also 2 of these:

Nebbia Sistema Lubrificazione Spray 8MM Tubo Aria Tornio Mill Esercitazione DB

A friend near my town buyed, I hate emulsion pump, it makes a lot of sludge. I use it occasionally, it's more time that I spend to clean pump than the time i use milling machine. I want to use a small fridge compressor and a bottle with emulsion, fast, "clean" and transportable. I want to put one on lathe and one mobile for drill and mill. They cost few bucks, the hose alone, here in italy cost more than 2 of these components shipped. I want to try

The Lc200 meter is quite good! the plastic case is something re used from another circuit, it shows 9v dc instead of 5vdc , power on off button is marked "ac- dc", no included instructions or manual, but at least it's good at measuring components. A strange thing I saw is the choice between high and low capacity button. The threshold is 1uf, I see that in this range the circuit is in low cap mode, and not in high as manual says.
Oddities aside, once I understand how it works, it gives nice measurements! Every start I check if resetted to "0", both for capacitance and inductance and then try measure.
in few words, not as immediate, but for the cost and above all for the precision is so good. There is anothe one better meter, but price is too high for my pocket, and for my usage.
here the manual:

http://mpl.jp/lc/LC200A%20%20EN%20V5.0.pdf

I tried different componenents, the measure of coil is so accurate that it's the same value I tested at coils factory with professional Lcr bridge. Capacitors are close, I was sick from the measured value of a standard mundorf capacitor... it's 10 years old component, I used it on speaker for some test, like other parts, the value measured is not so nice, compared to the name. Maybe it's my cap, or maybe the basic line is not so nice

[PJs]

The meter looks pretty good for a small price. As for the cap being old and out of 3% tolerance, you also have to keep in mind the meter is only good for 5% at either range of measurement 1-10uf (lo) or 1-100uf (hi). After 10 years it's probably seen its day and been a loyal component!

Hopefully this will help you dial in the circuit and make sure the components are up to spec.

Nice little mister for ~8 euro. Thanks for the update! ~PJ

[rendoman]

I sin of gluttony and I blew the ammeter, it was rated 1000v 200ma, with less than 1kv i see fire inside the instrument and now it has the 0 position at 190ma damn chinese meter! next time i put on negative rail.
... With this I will go to shooting range I will put the meter at 50 meter and try to shoot with 7.5x55mm swiss or 416 rem with scope!
I'm collecting info and measurements at the moment, waiting the frequency counter, but i'm glad to see that aside many troubles with noise and oscillation the sound pressure level is high! Sound is terrible, but volume is so high! less heat troubles, less current, less grid voltage... now i'm one step forward in the right path, light years away from winning. As usual recording microphone of camera is bad.

[C-Bag]

.. With this I will go to shooting range I will put the meter at 50 meter and try to shoot with 7.5x55mm swiss or 416 rem with scope!

LOL! There has been many a PIA (pain in a**) car, machine, etc I wished to do justice to. Never thought about taking it to a range and plugging it!

I know the sound is hard to tell with the camera mic but it's crazy how far you've come Stefano! This has been quite a ride...

[PJs]

Thanks for the new Video Stefano. Like C-Bag said; "it's crazy how far you've come". We've all had mishaps with equipment and maybe shooting them is a good recompense for poor quality¿ I accidentally blew a prized 15Amp "Weston" meter once and haunts me a bit to this day...but it was my bad...just had to move on.

I noticed the size of your plasma and it's related "fingers" without too much gyration. Feels a bit like it's being over driven and may account for some of the tinniness (not just the camera mic). Two things: First is your low filter may be off a bit and generally these devices work best in the mid to high range which is what you are shooting for. Second I would bet there is a quite a bit of ozone generated (careful) from a plasma that large which may not be optimal for a clean output because of the secondary plasma that ozone can create a Capacitance effect (lack a better term). Try looking at it through various color lenses. You can get colored (spectral) film pretty cheaply online. It will help you really see the the frequencies and plasma reactions to the input. Just thoughts!

Thanks! ~PJ

[rendoman]

thank you very much!
I got a bad news ...
I noticed a fault of the noval socket, after maybe 3\4 insertion of tube it loose strenght. Looking better the lower part peelings off the socket! The fault is of very poor quality of the rivet ( It's a low quality aluminum alloy ). For sure noise and connection troubles are linked to this component. I got mounted 2 of these noval, for pcl 82 and el84. I drilled the rivet, tomorrow I will find some good ones. I want to send a mail to the shop who sold me these parts just to know his position.
...it's like building a new house, begin to decorate and discover that the foundations are rotten
I sacrificed a new socket in order to test the goodness of materials... poor poor pooooooor quality!
Hope I will repair both sockets without desoldering the 3 stage before oscillator ...

Thanks for advice! I have to make some research of spectral and lenses, i never thinked to ozone as an external capacitor.
I'm trying to understand how this plasma runs , the "large flame" is just for aesthetics (at this point) maximum sound level is obtained with low flame and high audio imput. It's even strange that there is little ozone, only up to flame. I played with high volume for 3 hours but no smell of ozone in small room (4x3m +/-)

[PJs]

Thanks for the pictures. Sorry to hear about the socket troubles. Porcelain sockets are quite good usually, particularly for higher voltage/RF. From the first picture it looks to have a lot of stress from the wire gauge and components close to it. It's also a bit fragile from torque. A slight over torque from the mount screws can put hairline cracks in it. When I built that HV supply years ago, I used them but found some real nice silicone coated wire to use on it and very carefully torqued the screws. It is quite flexible and holds up to HV and RF. It had much larger rectifier tubes but that puts some strain on it too. Food for thought...

Hopefully your dealer will warranty them or discount some new ones for you.

I used to get optical stuff from Edmond Optics. Here is a link to a handy filter set that might work for you at a reasonable cost. You can also talk to some decent photo shops. They use them for various effects.

Here is a good starting place on Plasma. The links within can lead you into the rabbit hole of "The fourth state of matter" and all that is/has been explored in it.

Surprised about the ozone! Good luck on the sockets! ~PJ

[rendoman]

Hi!
new update, good for certain aspects
I tried to change imput filter at 5khz, nothing happened. The problem imho, is the audio stage. For sure walkman hasn't high output, not enough to drive at maximum pcl82, but the voltage at pentode is still low.
Second trouble, the sound improves quality with some more current then minimum, with actual circuit +/- 1cm flame. Plate is good, but grid 2 (5 watt max) glows red easily, and that's not completely good. Maybe I can improve tuning coils a bit more, I reached autofire but I cannot do miracles
After these considerations, I will build another plasma, in "test" frame. A friend gave me one 813 tube, and I will buy a Gu81 big tube, for sure over powered, but at least strong for my purpose.
For sure I will change audio amp, I'm studying about El34 - 12au7 tube.

I'm thinking about the frame, maybe it's a good thing to make a gu50 amplifier with custom output transformer, sell it, and use the proceeds for the plasma tweeter. I don't need more than 1 watt on my horn, it would be another parked component

I post a pic of some night ago, a friend built a big tesla coil, really nice and loud!