Hmm...neat tube , I want some!! 
Sorta like 6W6 I guess... anywho...
For class A1: maybe 200V supply, 50mA bias (-20V grid, 400 ohms per tube if cathode bias) = 10W dissipation (I'm sure you could push 15W Pd, vertical deflection is tough so it's going to be a hearty tube).
Loadline. Go up to the zero-bias curve and choose a point.. approx. double current (i.e. 100mA) is typical. That seems a little shallow so I'll say 125mA, which happens at 100V. The flipside of the point occurs at -40V, twice the bias voltage, about 5mA/255V. Thus Imax and Imin are 124 and 5mA respectively; Io (operating) is 50mA; Vmax is 257, Vo is 200, and Vmin is 100V. The slope of the loadline is the resistance, (Vmax-Vmin)/(Imax-Imin), or about 1.3k. You can also calculate distortion, based on:
Which can be simplified (algebraically speaking 
) to:
(That assumes my logic unit is still working.. it tends to get faulty with sleepiness... 
)
Anyway. That comes to 12%, but I just remembered that 2nd H is canceled in PP amps so you can ignore it
Have fun. Wonder how many responses popped in while I typed this...(when I started there were none )...
Tim
Sorta like 6W6 I guess... anywho...
For class A1: maybe 200V supply, 50mA bias (-20V grid, 400 ohms per tube if cathode bias) = 10W dissipation (I'm sure you could push 15W Pd, vertical deflection is tough so it's going to be a hearty tube).
Loadline. Go up to the zero-bias curve and choose a point.. approx. double current (i.e. 100mA) is typical. That seems a little shallow so I'll say 125mA, which happens at 100V. The flipside of the point occurs at -40V, twice the bias voltage, about 5mA/255V. Thus Imax and Imin are 124 and 5mA respectively; Io (operating) is 50mA; Vmax is 257, Vo is 200, and Vmin is 100V. The slope of the loadline is the resistance, (Vmax-Vmin)/(Imax-Imin), or about 1.3k. You can also calculate distortion, based on:
Code:
Imax + Imin
------------- - Io
2
2nd H % = -------------------- * 100
Imax - Imin
Code:
2nd H % = 50(Imax^2 - Imin^2) + 100Io(Imin - Imax)Anyway. That comes to 12%, but I just remembered that 2nd H is canceled in PP amps so you can ignore it
Have fun. Wonder how many responses popped in while I typed this...(when I started there were none
)...Tim
Forgot the graph I prepared..
The loadline shown is SE. For PP, each tube needs to see that - so 1.3k per half (either side of the CT). So the anode-to-anode load must be four times, or 5.2k (you needn't be so exact, a 4 or 6k would work about the same ).
Now, this is where I keep forgetting things... Do the tubes act in series, hence a-a = 4*single Rl? Or do they act in parallel, giving a-a nearer 1x? Or somewhere inbetween, say one tube is half cutoff (half Gm or Rp, take your pick) and the load is suddenly on a single tube!
Tim
The loadline shown is SE. For PP, each tube needs to see that - so 1.3k per half (either side of the CT). So the anode-to-anode load must be four times, or 5.2k (you needn't be so exact, a 4 or 6k would work about the same
).Now, this is where I keep forgetting things... Do the tubes act in series, hence a-a = 4*single Rl? Or do they act in parallel, giving a-a nearer 1x? Or somewhere inbetween, say one tube is half cutoff (half Gm or Rp, take your pick) and the load is suddenly on a single tube!
Tim
Attachments
how about a schematic?
Scroll down this page for one idea.
http://hollowstate.netfirms.com/DIY_files/proto.htm
here is another
http://tinpan.fortunecity.com/saints/668/primer/6ck4-pp.gif
http://tinpan.fortunecity.com/saints/668/primer/index.html
Something to start with anyway.
Cheers
Craig Ryder
Scroll down this page for one idea.
http://hollowstate.netfirms.com/DIY_files/proto.htm
here is another
http://tinpan.fortunecity.com/saints/668/primer/6ck4-pp.gif
http://tinpan.fortunecity.com/saints/668/primer/index.html
Something to start with anyway.
Cheers
Craig Ryder
That guy was probably going from his junk pile, but if you must do it like that, use a lower voltage transformer or choke input.
Statue
OK, I have a vision in my mind of our glorious worker hero with handsomely chiselled features looking towards a glorious future lit by the glow of an 845 and guided by the wisdom of RDH4, but should he not have one foot on a vanquished foe? Perhaps a bespectacled and biroed silicon fab type clutching a squashed 741 with a look of despair on his face?
OK, I have a vision in my mind of our glorious worker hero with handsomely chiselled features looking towards a glorious future lit by the glow of an 845 and guided by the wisdom of RDH4, but should he not have one foot on a vanquished foe? Perhaps a bespectacled and biroed silicon fab type clutching a squashed 741 with a look of despair on his face?
Socialist Realism
Purges have already been mentioned.
The vigilant Party member will always be on the look out for enemies of the State - "Decadent Formalists". Of course "Formalism" or accusations of same got my heroes Prokofiev and Shostakovich into all sorts of trouble.
For the bourgeois running-dogs and lackeys "formalism" can mean anything that the Party does not approve of this week.
For many of the recent years, "Formalists" have included those who do not use 105dB/W loudspeakers, those who have allowed the presence of s*****n in their developments, and worst of all those who consider that push-pull has a future!
Collectivisation may have a point: i.e. I get your 437As and EC8020s and you get my 6BC8s.
Lastly, we would probably need a "Terror".
This is easy: just have a look at one of my bench lash-ups.
7N7 (imagine a clenched-fist "smilie")
Purges have already been mentioned.
The vigilant Party member will always be on the look out for enemies of the State - "Decadent Formalists". Of course "Formalism" or accusations of same got my heroes Prokofiev and Shostakovich into all sorts of trouble.
For the bourgeois running-dogs and lackeys "formalism" can mean anything that the Party does not approve of this week.
For many of the recent years, "Formalists" have included those who do not use 105dB/W loudspeakers, those who have allowed the presence of s*****n in their developments, and worst of all those who consider that push-pull has a future!
Collectivisation may have a point: i.e. I get your 437As and EC8020s and you get my 6BC8s.
Lastly, we would probably need a "Terror".
This is easy: just have a look at one of my bench lash-ups.
7N7 (imagine a clenched-fist "smilie")
OSCAR WILDE.
Hi,
LOL..You two are the max.
Well, with war nearing...yes, better brace yourselves, I can only say this: valves will survive nukes, sand won't.
I have the simplest of tastes, I'm only satisfied with the best...
100 years + of valves and still going strong, one of the best investments on the stock markets and hey, if you're a bit clever they don't sound bad either...a clear winner.
Cheers,
Hi,
LOL..You two are the max.
Well, with war nearing...yes, better brace yourselves, I can only say this: valves will survive nukes, sand won't.
I have the simplest of tastes, I'm only satisfied with the best...
100 years + of valves and still going strong, one of the best investments on the stock markets and hey, if you're a bit clever they don't sound bad either...a clear winner.
Cheers,
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