Sure I remember in the 1970s and even 1980s 1% metal film resistors were exotic and reserved for high end. Now some folks here slag 1% MF unless they are the right brand.
That's the only way to go! T&M keeps you honest with yourself. Listening keeps the T&M honest.
-Chris
-Chris
Thks for reminder re AOE V3. I think I have V1. Should be a nice update for my library.
Had a lot of fun in Kathmandu and now back at condo in Bangkok.
-RNM
Had a lot of fun in Kathmandu and now back at condo in Bangkok.
-RNM
Where did this end up at? The 4000v HV electro amp?
suggested -- stacking topology/config.,
THx-RNMarsh
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Yeah but that stack can't swing the output voltage 4kV, or even ~1kV for that matter.
Check out these ones RNM.
Self-cascoding, a tool for creating ultra high voltage building blocks:
Build me a ss direct drive ESL amp, please
ps. I think you are a bit exhausted after the Kathmandu trip! 🙂
Check out these ones RNM.
Self-cascoding, a tool for creating ultra high voltage building blocks:
Build me a ss direct drive ESL amp, please
ps. I think you are a bit exhausted after the Kathmandu trip! 🙂
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That redraw can't work the output does not swing more than 250V no matter how high you stack it. Your original article stated in the text that it is only good as a logic output (when set up correctly). I don't think the other two links came to fruition either, too many opportunities for smoke.
Just throwing out an idea --- to be modified or ??? to suit the situation.
Surely there are such circuits in existence???? Stacking, rather than using one single device?
yes, i am tired. Travel is getting harder after 70 yrs. Wonder what it will be like after 80?
THx-Richard
Surely there are such circuits in existence???? Stacking, rather than using one single device?
yes, i am tired. Travel is getting harder after 70 yrs. Wonder what it will be like after 80?
THx-Richard
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Thx... yes, those example will do fine.... I was just thinking of the stacking principle for jan to explore.
THx-RNM
I think in the very least the forum safety rules should be observed, these circuits are very dangerous and need some warning.
If the modulation is 250 volts with a bias of 3750 then the active driver need not have the full voltage across it. In simplified form a grounded driver with a 3750 volt Zener would work.
Now as a Zener or even a stack would be a bit outside practical it could be done with a transistor stack and voltage divider. The active transistor would modulate the bottom resistor in the voltage divider stack.
The down side is the increased current draw.
But for fun you could also do it with a string of neon lamps. Would require a striker circuit though. Way more interesting to look at.
Now as a Zener or even a stack would be a bit outside practical it could be done with a transistor stack and voltage divider. The active transistor would modulate the bottom resistor in the voltage divider stack.
The down side is the increased current draw.
But for fun you could also do it with a string of neon lamps. Would require a striker circuit though. Way more interesting to look at.
I don't think that's the case. The DIY articles I've seen use a 50:1 step up transformer as output drive.
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That would put 100 watts 8 ohms to under 1500 volts. So I suspect you don't need to modulate the full voltage.
I did used to have a pair of electrostatic loudspeakers. (Lost them in a flood 2004) To play at a decent volume they could have used several thousand watts. Unfortunately their power handling was about 500 watts maximum. (I got them for really cheap. The owner traded them in after his dog used one for a fire hydrant. That killed it. I had to change a diode in the power supply. Fortunately I had a bunch of 10KV diode stacks from some prior work.)
I did used to have a pair of electrostatic loudspeakers. (Lost them in a flood 2004) To play at a decent volume they could have used several thousand watts. Unfortunately their power handling was about 500 watts maximum. (I got them for really cheap. The owner traded them in after his dog used one for a fire hydrant. That killed it. I had to change a diode in the power supply. Fortunately I had a bunch of 10KV diode stacks from some prior work.)
There is nearly pure silver wire available from jewelry suppliers. What is better than that?
I don't think these MOSFET cascades are useful. It always looks so obvious, at first glance. Until you start to figure out the details, the power dissipated in the bias strings, the dynamic behaviour of such a string which basically is a bunch of R-C's with source followers, and cost, just to name a few.
With MOSFETs and IGBTs available with breakdown limits of 4.5kV, you don't need those cascades either. With those devices you can build a class B output stage that swings 4.2kV pk-pk at 20kHz across 1200pF from just 12mA bias current. Way to go.
Jan
With MOSFETs and IGBTs available with breakdown limits of 4.5kV, you don't need those cascades either. With those devices you can build a class B output stage that swings 4.2kV pk-pk at 20kHz across 1200pF from just 12mA bias current. Way to go.
Jan
Using the 4 Ohm tap, 500V p-p is ~180 rms or not even a Watt at 1:50. Transformer coupling also goes both ways above and below the bias so with a center tap even 10kV p-p is no problem.
180 RMS / 50 = 3.6
3.6 x 3.6 / 4 = 3.24 watts
Or for a 10 KV bias and full modulation
7071 RMS / 50 = 141.42
141.42 x 141.42 / 4 = 5000 watts.
So if the 50:1 tap is 8 ohms it drops to 1250 watts required from the amplifier.
Of course the calculations are nonsense where the impedance of the panel is more than 8 x 50 x 50 = 20,000 ohms.
As maximum power is usually required below 300 hertz the capacitance needs to be below .027 uF.
But we all know that the noise from something where an 8-leg is involved is much worse than that from 3-legs, even if it is lower
Edit: just saving JC some typing here... ;-)
Jan
The noise is worse even if it's lower. My brain is so confused by this statement.
Please explain.
It was a joke that even if you had a matched noise output from a discrete and IC circuit (or lower noise in the IC), the IC would still sound noisier. Nothing serious about it. 🙂
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