Hi again.
I assume you did not already build this circuit (ie. did not breadboard it), and maybe its the 1st time you build an amp with choke input? If it is, then its important to find out if your input choke can handle the job as an input choke.
An input choke is not doing the same thing as a filter choke. I think you probably understand this.
If that 1st input choke is not quite up to the task, it will vibrate and maybe even hum. That is a bit of a bummer to find out after you have built the whole amplifier.
This is something you will want to know sooner vs. later. If it is not "up to the task" then you need to do some re-engineering, maybe even get a different input choke.
If you are using the kind of chokes that Thomas Mayer uses (Lundahl), you should be fine. If you are using "modestly priced" chokes, then maybe (or not).
I assume you did not already build this circuit (ie. did not breadboard it), and maybe its the 1st time you build an amp with choke input? If it is, then its important to find out if your input choke can handle the job as an input choke.
An input choke is not doing the same thing as a filter choke. I think you probably understand this.
If that 1st input choke is not quite up to the task, it will vibrate and maybe even hum. That is a bit of a bummer to find out after you have built the whole amplifier.
This is something you will want to know sooner vs. later. If it is not "up to the task" then you need to do some re-engineering, maybe even get a different input choke.
If you are using the kind of chokes that Thomas Mayer uses (Lundahl), you should be fine. If you are using "modestly priced" chokes, then maybe (or not).
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I don’t have PSU II anymore and our only home computer is a Mac and I’m Mac stupid.
Are you suggesting adding a cap directly after the choke before splitting the supply? 350V is useable, but I may need to add capacitance up front to bring the B+ up at the cost of some regulation. I used a .01uf poly rated at 4KV.
Are you suggesting adding a cap directly after the choke before splitting the supply? 350V is useable, but I may need to add capacitance up front to bring the B+ up at the cost of some regulation. I used a .01uf poly rated at 4KV.
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yup. That is where you want it.
If I were you, I would draw right off the choke to the OPT for each channel. Don't worry about channel separation on the "finals" so much unless you have extra cash to burn. Don't worry so much about ripple either - your choke is 10Hy. Maybe a second filter choke would be nice though (it can be a cheaper one). LCLC supply...
I would however use separate RC networks for the input/driver stages. Again, this is just my 2 cents. If channel separation is really an issue, then you can easily address it later.
Choke input supply is worth keeping, if you can manage it.
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If I were to forego the separation effort, I’d pull one leg and run both plate leads off one 235Uf cap and add a 50uf in front of the resistor after the choke. Maybe that’s the way to go. If going to feed the drivers off that 0A3 string regulator on the bottom. I doubt I will see any channel interference.
Hi, I am looking to use the 6BY5G for the first time but have only one 6.3v heater rail to share with input tubes and 6BY5G heater.
The heater in respect to cathode + 100v and heater respect to cathode - 450v
There are a few options out there but like the idea DHT Rob came up with
DHTRob - Mu-stage headphone amplifier with type '27 triode and 7788 pentode
http://tubedata.jp/sheets/127/6/6BY5G.pdf
I would like to run 350v AC 150mA load and enclosed schematic lifting the heater earth
but the 150K would need to rise to say 220K ? shown in the dhtrob URL
Any ideas as i need 425v DC
The heater in respect to cathode + 100v and heater respect to cathode - 450v
There are a few options out there but like the idea DHT Rob came up with
DHTRob - Mu-stage headphone amplifier with type '27 triode and 7788 pentode
http://tubedata.jp/sheets/127/6/6BY5G.pdf
I would like to run 350v AC 150mA load and enclosed schematic lifting the heater earth
but the 150K would need to rise to say 220K ? shown in the dhtrob URL
Any ideas as i need 425v DC
Apologies for the question, but what does “full-wave hybrid bridge rectification” look like? If you Google hybrid bridge like the title says you get all kinds of dental work! I assume you have two forward conducting dampers and two backward blocking SS diodes.
Could somebody explain the inductive kick-back in this case and how to determine the voltage required for by-pass caps, other than “buy the highest voltage you can find”. Is this any different from other SS bridges, where by-pass capacitors are sometimes used or often not used?
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> what does “full-wave hybrid bridge rectification” look like?
I assume:
http://www.valvewizard.co.uk/bridge3.jpg
from:
The Valve Wizard: Hybrid Bridge Rectifier
I do not see a problem here. The 6V feed can even be grounded, since the hoped-for 425V is less than the 450V rating.
I assume:
http://www.valvewizard.co.uk/bridge3.jpg
from:
The Valve Wizard: Hybrid Bridge Rectifier
I do not see a problem here. The 6V feed can even be grounded, since the hoped-for 425V is less than the 450V rating.
VinylSavor: The Octal Phono Preamplifier, Part 3 : Power Supply
This seems a solution
Both 6v on rectifier > SS Bridge> small signal tubes
This seems a solution
Both 6v on rectifier > SS Bridge> small signal tubes
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