First answer the question, why use any kind of capacitance multiplier?
Start with that.
Then discover the disadvantage of a capacitance multiplier . . .
. . . In terms of storing energy, a capacitance multiplier does not do that.
Only a capacitor or a storage battery can do that . . .
. . . Well, an inductor can store energy, but it can not be used to substitute for a capacitor or storage battery.
Start with that.
Then discover the disadvantage of a capacitance multiplier . . .
. . . In terms of storing energy, a capacitance multiplier does not do that.
Only a capacitor or a storage battery can do that . . .
. . . Well, an inductor can store energy, but it can not be used to substitute for a capacitor or storage battery.
Well , first of all , the capacitance multiplier is for reducing ripple/noise , like a low pass filter , who claimed it is for storing energy ? This is not its purpose , the energy is stored in the main filter ...
For the original question I don't know , should be possible to use tubes .
For the original question I don't know , should be possible to use tubes .
Hi, In truth, I have been using capacity multipliers and gyrators in my power supply projects for some time.
So I don't understand what you mean.
Maybe I explained myself wrong because I'm not a native English speaker.
I was curious to know if anyone had made capacity multipliers (and gyrators too) .. but made with tubes instead of transistors and / or mosfets.
🙂
So I don't understand what you mean.
Maybe I explained myself wrong because I'm not a native English speaker.
I was curious to know if anyone had made capacity multipliers (and gyrators too) .. but made with tubes instead of transistors and / or mosfets.
🙂
1. One way to make low ripple power supplies: use "capacitance multipliers".
Depending on the active device part, it may, or may not have a low output impedance.
You can make capacitance multipliers with Bipolar PNP and NPN, JFETs, MOSFETs, and . . .
Vacuum Tubes.
The parameters of the above parts determines the characteristics of the capacitance multiplier.
One important characteristic of a capacitance multiplier is the Voltage loss through the device (and the consequential Voltage x Current Power loss).
PNPs and NPNs have the lowest saturation voltage, JFETs and MOSFETs have more voltage loss, and Tubes have the highest voltage loss (and highest power loss).
The voltage loss of the part, plus the ripple voltage of the DC to the input of the capacitance multiplier, determine the Burden Voltage of the capacitance multiplier. The burden voltage x the load current is the power loss of the capacitance multiplier.
In order to be very effective, if you use a tube as a capacitance multiplier, you have to worry about the transconductance of the tube. It must be very high transconductance, or the output impedance of the capacitance multiplier will be very high.
PNP and NPN output impedance is approximately 26/load mA.
JFETs and MOSFETs output impedance is approximately 1/Operating transconductance, Gm.
Tube output impedance is approximately 1/Operating transconductance, Gm.
The advantage of a Tube capacitance multiplier is . . .
. . . it looks good!
2. Another way to make low ripple power supplies is to use a Voltage Regulator IC; or a PNP, NPN, JFET, MOSFET, or Vacuum Tube Voltage Regulator circuit.
3. Another way to make low ripple power supplies is to use plenty of capacitance and inductance in a CLC, CLCRC, LCLC or LCRC filter.
Active devices are not required.
With proper design, and good parts, a LCLC filter can also have good voltage regulation.
Do it your way, we all like variety.
Just my opinions.
Depending on the active device part, it may, or may not have a low output impedance.
You can make capacitance multipliers with Bipolar PNP and NPN, JFETs, MOSFETs, and . . .
Vacuum Tubes.
The parameters of the above parts determines the characteristics of the capacitance multiplier.
One important characteristic of a capacitance multiplier is the Voltage loss through the device (and the consequential Voltage x Current Power loss).
PNPs and NPNs have the lowest saturation voltage, JFETs and MOSFETs have more voltage loss, and Tubes have the highest voltage loss (and highest power loss).
The voltage loss of the part, plus the ripple voltage of the DC to the input of the capacitance multiplier, determine the Burden Voltage of the capacitance multiplier. The burden voltage x the load current is the power loss of the capacitance multiplier.
In order to be very effective, if you use a tube as a capacitance multiplier, you have to worry about the transconductance of the tube. It must be very high transconductance, or the output impedance of the capacitance multiplier will be very high.
PNP and NPN output impedance is approximately 26/load mA.
JFETs and MOSFETs output impedance is approximately 1/Operating transconductance, Gm.
Tube output impedance is approximately 1/Operating transconductance, Gm.
The advantage of a Tube capacitance multiplier is . . .
. . . it looks good!
2. Another way to make low ripple power supplies is to use a Voltage Regulator IC; or a PNP, NPN, JFET, MOSFET, or Vacuum Tube Voltage Regulator circuit.
3. Another way to make low ripple power supplies is to use plenty of capacitance and inductance in a CLC, CLCRC, LCLC or LCRC filter.
Active devices are not required.
With proper design, and good parts, a LCLC filter can also have good voltage regulation.
Do it your way, we all like variety.
Just my opinions.
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Thanks for the full explanation, thanks for your time.
I searched for days, on the internet, if I could find schemes for multipliers and gyrators made by tube ... but nothing more total.
I wonder if no one has ever made them with tubes .. even just for the curiosity of the obtainable sound.
In addition, a tube gyrator could be used on an anode ........... a kind of CCS with an extra cap!
Is there any place where I can find outlines and info?
Maybe I'm wrong keywords in google ... Thanks
I searched for days, on the internet, if I could find schemes for multipliers and gyrators made by tube ... but nothing more total.
I wonder if no one has ever made them with tubes .. even just for the curiosity of the obtainable sound.
In addition, a tube gyrator could be used on an anode ........... a kind of CCS with an extra cap!
Is there any place where I can find outlines and info?
Maybe I'm wrong keywords in google ... Thanks
I would say it is "an electronic choke". They say "FILTER REACTOR". The .05MFD cap is gyrated into a choke. On the last page it suggests it chokes about like 20H-30H of iron.
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A 30H choke probably has less DCR than the electronic version's "equivalent DCR", so a real choke is more power efficient.
But the 30H choke might be more expensive, might weigh more, might take more real estate (if only to keep the magnetic spray away from sensitive parts and circuits, and needs a filament secondary to work.
Again, the tube looks good.
But the 30H choke might be more expensive, might weigh more, might take more real estate (if only to keep the magnetic spray away from sensitive parts and circuits, and needs a filament secondary to work.
Again, the tube looks good.
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A capacitor multiplier is just a cathode follower, it's easy. What else do you need to know?
Hi, I would like to know how it is done, that is a scheme, both for the capacity multiplier and for the gyrator.
I would like to make both of them to test them on power supplies and, for the gyrator, to test it on the head of an anode.
I saw the datasheet for that pentode, also advertised as "choke", but I didn't understand if the things I would like to experiment can also be done with other tubes, such as high GM,.... double triodes, or if you need a pentode. .or if you necessarily need a pentode designed for that specific use.
My ideas are a bit vague! 🙁
I would like to make both of them to test them on power supplies and, for the gyrator, to test it on the head of an anode.
I saw the datasheet for that pentode, also advertised as "choke", but I didn't understand if the things I would like to experiment can also be done with other tubes, such as high GM,.... double triodes, or if you need a pentode. .or if you necessarily need a pentode designed for that specific use.
My ideas are a bit vague! 🙁
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You are looking to be spoon fed, read about how triodes work, look at a cathode follower circuit, compare it with the popular solid state capacitance multiplier circuits, think about how to bias the tube. You will read that a good cathode follower needs high transconductance.
Ok, thanks.
I thought someone had already done it and to find things on the net as for everything else. I see instead that it is a rare thing. thanks I'll try to feed myself!
I thought someone had already done it and to find things on the net as for everything else. I see instead that it is a rare thing. thanks I'll try to feed myself!
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Joined 2009
Paid Member
that’s the spirit! have a go at it, post your circuit ideas and help will come from the forum denizens
A tube-based capacitance multiplier is rare because it's nearly worthless. Not only you waste a lot of power in the pass element, you also waste considerable power in the filament of a high gm tube. If you're going to that much trouble, you may as well add a reference and make it into a regulator.
Bigun makes a good point. It's best to try and understand the science instead of copying random things from the internet. Imagine what would happen if you tried surgery after watching an eccentric doctor on youtube 😀