drop 6.3 to 5v for recto

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mark enger
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drop 6.3 to 5v for recto

Post by mark enger »

Is it possable? Thanks mark
tubeswell
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Re: drop 6.3 to 5v for recto

Post by tubeswell »

Voltage divider? (You'll lose a bit of current)
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Structo
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Re: drop 6.3 to 5v for recto

Post by Structo »

How about a couple silicon diodes of the proper current rating?

It would drop 1.2v
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rdjones
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Re: drop 6.3 to 5v for recto

Post by rdjones »

Don't try this on a typical guitar rectifier tube.
The filament is connected to B+.

rd
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Structo
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Re: drop 6.3 to 5v for recto

Post by Structo »

Yeah, you're right. :oops:
Tom

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mark enger
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Re: drop 6.3 to 5v for recto

Post by mark enger »

so no not possable, ill go ss the. i have some ss plug ins i could use being the the sockets there already, now for sag R maybe a sag control? mark
Jana
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Re: drop 6.3 to 5v for recto

Post by Jana »

How about putting a 0.68 ohm, 5 watt resistor in series with the leg of the 6.3 volts that is not common with the B+? That should drop about 1.3 volts with a 2 amp load.
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VacuumVoodoo
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Re: drop 6.3 to 5v for recto

Post by VacuumVoodoo »

Both legs are common with B+, there's 5V AC riding on B+ if you look closely with an oscilloscope.
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Jana
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Re: drop 6.3 to 5v for recto

Post by Jana »

Yes, I understand that the 5v winding rides at the B+ level. However, the B+ would not be going "through" the dropping resistor.
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VacuumVoodoo
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Re: drop 6.3 to 5v for recto

Post by VacuumVoodoo »

So, what is the problem with additional max 250mA when you already are pulling 2 or 3 amps through that resistor? You need a 5W or 8W resistor anyway. Any minute sag this introduces is only of academic interest , if any at all.
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martin manning
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Re: drop 6.3 to 5v for recto

Post by martin manning »

Suppose you experienced a short somewhere on the DC side of the HT... If that momentary (until a fuse or something else opens up) surge current comes through the rectifier's filament, maybe it would take the rectifier out too?
Prairie Dawg
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Re: drop 6.3 to 5v for recto

Post by Prairie Dawg »

Why not use 6v rectifier tubes? 6CA4, 6AX5. 6X4 and a number of loktals are six volt, or say 2 3dg4s in series?
If you believe in coincidence you're not looking close enough-Joe leaphorn
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renshen1957
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Re: drop 6.3 to 5v for recto

Post by renshen1957 »

Prairie Dawg wrote:Why not use 6v rectifier tubes? 6CA4, 6AX5. 6X4 and a number of loktals are six volt, or say 2 3dg4s in series?
+1 :D
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