Tube Rectifer, Safety Diodes & Max C1 Question
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Tube Rectifer, Safety Diodes & Max C1 Question
If you have silicon diodes in front of and in series with the tube rectifier (the typical protection diodes often used) can you get away with a larger than recommended max first filter cap? Just thinking this would solve the modern sino-ruskie 5AR4s used w/80mf on the Rocket. If so, how high can you go?
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Stevem
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next post.
Last edited by Stevem on Thu Jul 14, 2016 12:03 pm, edited 1 time in total.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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Stevem
- Posts: 5144
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
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A great set up for applying added uf is a slow start Recto like a AR4 or V4 ,five volt type along with 6 added parts, 4 diodes, 1N5399 ( fast recovery would be better) and two 250 ohm 25 watt resistors.
It goes together like this.
One diode between pins 6 and 7 with K at 7.
Next one between 7 and 5 with K at 5.
Next between 1 and 4 with K at 1.
Next between 1 and 3 with K at 3.
One resistor goes between 8 and 5, and the other from 3 to 8.
With this set up the diodes take the turn on surge which will let you up the cap uf amount, yet you still get Recto tube sag
Another big plus is that if the Recto blows you can just pull it, replace the fuse abd run on the diodes but with a higher B+ voltage of course so the filters need to be able to handle that condition .
I have never tryed it , but with the diodes coming on so fast I would guess that even a Recto with out a seperate heater could withstand a bit more than the book rated uf value!
A thermistor is another thing to look into for a small added soft start I would guess.
In regards to how high in uf you can go, I have never pushed it, but in one amp I have 150 uf for the first filter node.
It goes together like this.
One diode between pins 6 and 7 with K at 7.
Next one between 7 and 5 with K at 5.
Next between 1 and 4 with K at 1.
Next between 1 and 3 with K at 3.
One resistor goes between 8 and 5, and the other from 3 to 8.
With this set up the diodes take the turn on surge which will let you up the cap uf amount, yet you still get Recto tube sag
Another big plus is that if the Recto blows you can just pull it, replace the fuse abd run on the diodes but with a higher B+ voltage of course so the filters need to be able to handle that condition .
I have never tryed it , but with the diodes coming on so fast I would guess that even a Recto with out a seperate heater could withstand a bit more than the book rated uf value!
A thermistor is another thing to look into for a small added soft start I would guess.
In regards to how high in uf you can go, I have never pushed it, but in one amp I have 150 uf for the first filter node.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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martin manning
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- Location: 39°06' N 84°30' W
Re: Tube Rectifer, Safety Diodes & Max C1 Question
The silicon diodes won't limit the current flowing through the vacuum rectifier so they won't offer any additional protection for running a larger reservoir. For that you'd have to add more series resistance.rp wrote:If you have silicon diodes in front of and in series with the tube rectifier (the typical protection diodes often used) can you get away with a larger than recommended max first filter cap? Just thinking this would solve the modern sino-ruskie 5AR4s used w/80mf on the Rocket. If so, how high can you go?