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if the current/voltage requirements are within specs of each tube.what's the differentiating feature to choose one over the other? It can't be price since these tubes are all cheap.
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Just obey the anode dissipation... 450V * 100mA = 4.5W.
The 6CJ3 (compactron) is rated for PaMax = 6.5W. The 6AX4
has PaMax=5.0W. That said, a single pair of EL34's running at
the usual 450V/50mA op point will just barely be taken care of
by a pair of 6AX4's... Dont expect these to power a stereo KT88
amp. On the other hand, for monoblocks, the damper tubes are definitely an option over the 5AR4. For preamps, or small amps
based on 6V6 or EL34, you have lots of room to wiggle.On more thing... A pair of damper diodes NEEDS IT OWN 6.3/12/25V
filament winding... Do not share the winding with any other tubes.
For a pair of dampers, you need 3A at 6V. :)
the dissipation is the voltage ACROSS the tube, which is around 15-20 volts, times the amperage, which works out to around 1.5-2 volts. Also the 6CJ3 uses a Novar socket, not a Compactron.
Hey Jim, wouldn't you calculate the dissipation as the drop across the tube times the current? The 6cj3 (from memory) drops about 15 volts at full load, so a tube passing 100 ma is dissipating 1.5 watts, a pair can handle a pretty heavy load. You are correct regarding the need for separate heater winding, mainly due to noise coupling issues.
I've driven the input tubes to an amp off the same winding as the damper diodes, and I'm damned if I can hear any ill effects. What should one expect? It clearly works, so where is there a drawback? What am I missing?
You're right, at least as far as 6D22S is concerned. It tolerates 600v h-k voltage, so it will happily share with other tubes.As a matter of interest, Svetlana reported that 6D22S performed almost as well with only 5v on the heater, which makes it potentially very versatile.
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Hi there> > On more thing... A pair of damper diodes NEEDS IT OWN 6.3/12/25V
> > filament winding... Do not share the winding with any other tubes.Could you please elaborate on this warning?
I currently have a pair of 6DW4 and a quad of 6GF7 (dual triodes in stereo PP) on one 6.3v supply.
you use one 6BY5GA. And they require a 6.3 or 12.6 volt filament winding and alot of existing trannys have 5 volt hipot windings for a rectifier.
"I take you as you are
And make of you what I will,
Skunk-bear, carcajou, bloodthirsty
Non-survivor.
Lord, let me die but not die out." THE LAST WOLVERINE by James Dickey
surely there's no 12BY5G?
n/t
Yes, it is 6.3v with both diodes in the same envelope. but I prefer to use damper diode filaments in series if I'm using two seperate envelopes rather than parallel. If one craters then it doesn't unbalance the transformer. If you wired the 2 single damper filaments in parallel then you might possibly be setting it up to fail if one goes south. Ray
"I take you as you are
And make of you what I will,
Skunk-bear, carcajou, bloodthirsty
Non-survivor.
Lord, let me die but not die out." THE LAST WOLVERINE by James Dickey
Since the cathodes are isolated, you can probably run them in series. You won't get the possible benefit of running them out of phase but it's not a huge issue.
I used a pair of 19AU4's (I had an 18VCT power transformer from Radio Shack)The 19AU4's have lasted for years (I think I changed them once, but the originals I used were used tubes from old TVs) - a pair of them is just as good as a GZ34 at much less cost. The 6AU4 might be more appropriate if you have a normal filament transformer.
My application is a power supply for a 50W per channel EL34 amplifier. B+ is about 450V, and the supply has good regulation.
When the tube damper diodes were made years ago,they were used primarily in television horizontal deflection circuits and they would also supply the DC source voltage to the horizontal output tube plate cap..You need to look up the ratings of each tube but black and white used one type with less current and piv plate voltage and color sets used another heavier type but they were all same principle.
The reason there are so many different types and ratings is every manufacturer of tv sets wanted to be different for whatever reasons..They had octals and 9 pins and 12 pin compactron types but all did the same basic thing.
Pick a rectifier by output current and peak inverse plate voltage..They(damper diodes) actually produce high currents than say a 5u4 and have a higher piv even tho they physically much smaller than a 5u4.Most use two of them together and you will be able to swing a nice steady supply voltage..
The 6dw4 would be a good choice.
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