On the second page of this pdf, there's a section for "general operation and characteristics". What is the difference in the two columns of data?
I'm trying to figure out what my max plate voltage is for these tubes.
http://tubedata.milbert.com/sheets/049/6/6Y6GA.pdf
Does the "class A" chart include A/B or no?
I'm studying the electrical aspects of a 2 x 6y6 tube rectified power amp.
I'm trying to figure out what my max plate voltage is for these tubes.
http://tubedata.milbert.com/sheets/049/6/6Y6GA.pdf
Does the "class A" chart include A/B or no?
I'm studying the electrical aspects of a 2 x 6y6 tube rectified power amp.
So they just show a set of data for 135v plate voltage just for the hell of it, and doesn't indicate any sort of max rating?
Tell me if this is correct.
2 x 6y6ga tubes each get 200v to the plates with 12.5W dissipation each. That equates to 62.5mA that each tube needs.
Let's say these two tubes get B+ through a 6x5gt rectifier that's rated for max rectified current to be 70mA. Certainly sounds like it wouldn't work...
here's the rectifier data: http://www.r-type.org/pdfs/6x5g.pdf
I'm gonna come up with some more stupid questions, I'm sure.
2 x 6y6ga tubes each get 200v to the plates with 12.5W dissipation each. That equates to 62.5mA that each tube needs.
Let's say these two tubes get B+ through a 6x5gt rectifier that's rated for max rectified current to be 70mA. Certainly sounds like it wouldn't work...
here's the rectifier data: http://www.r-type.org/pdfs/6x5g.pdf
I'm gonna come up with some more stupid questions, I'm sure.
MAX ratings were on the first sheet. Note, this is a rather brief data sheet. Most have a lot more info.
Cheers
In
They tell you that max rating is 200V. 135V is both a recommended screen voltage and, perhaps, a typical supply rail for an AC/DC set in the USA? Or a set with only a heater transformer, but directly rectified mains?Sea Biscuit said:
So it says the 6x5gt rectifier is rated for 210mA peak current on each anode, but only 70mA DC current? How does that work?
Does plate dissipation go against that 70mA rating of the rectifier, or only the grid dissipation?
Does plate dissipation go against that 70mA rating of the rectifier, or only the grid dissipation?
The peak current is rated "before destruction", the full-wave rectified current is 70mA per the datasheet. So that is not enough to supply two 6Y6GT for push-pull operation, since each tube would require ~65mA of idle current.
Hmmm.. I could go with a 6ax5gt rectifier instead, but it uses twice the heater current of the 6x5 and would put me right at the max current rating of the 6.3v windings of the PT.
Rectifier current is basically a repeated pulse. Peak current tells you how high this pulse can be. Average or DC current tells you how much on average you can pass.
I have done some experiments on the 6Y6. It was a long time ago, but more will be coming soon.
The maximum plate voltage rating is 200 volts. It can be violated within reason without serious consequence if the dissipation and screen voltages are kept in spec.
The maximum screen voltage rating is 135 volts. This one needs respect. Some tubes will exhibit runaway or bias creep at 160 volts, while some will eat 200 volts without a problem.
Any time you push the ratings on a tube the grid circuit resistance must be as low as possible. The 6Y6 wants a 100K maximum with fixed bias, which is quite low. If you are going to bend the ratings, you need to be well below that. Cathode follower, mosfet or transformer drive is suggested.
The 6Y6 was developed when rectified wall outlet was common, but the fact that AC or DC heater operation is stated suggests another reason. The 6Y6 was used in aircraft and shipboard equipment where the B+ was derived from a 28 Volt source with a mechanical rotary inverter (Dynamotor). Most of the 6Y6's that I have did come from military surplus.
The maximum plate voltage rating is 200 volts. It can be violated within reason without serious consequence if the dissipation and screen voltages are kept in spec.
The maximum screen voltage rating is 135 volts. This one needs respect. Some tubes will exhibit runaway or bias creep at 160 volts, while some will eat 200 volts without a problem.
Any time you push the ratings on a tube the grid circuit resistance must be as low as possible. The 6Y6 wants a 100K maximum with fixed bias, which is quite low. If you are going to bend the ratings, you need to be well below that. Cathode follower, mosfet or transformer drive is suggested.
The 6Y6 was developed when rectified wall outlet was common, but the fact that AC or DC heater operation is stated suggests another reason. The 6Y6 was used in aircraft and shipboard equipment where the B+ was derived from a 28 Volt source with a mechanical rotary inverter (Dynamotor). Most of the 6Y6's that I have did come from military surplus.
Thanks for all the replies.
Shows 10uF capacitance for 6ax5. There's also a note that says it can use more but [insert misunderstood technical speak]
Is there value in exceeding the spec uF, and inversely are there drawbacks for adhering to spec?
http://frank.pocnet.net/sheets/049/6/6AX5GT.pdf
Shows 10uF capacitance for 6ax5. There's also a note that says it can use more but [insert misunderstood technical speak]
Is there value in exceeding the spec uF, and inversely are there drawbacks for adhering to spec?
http://frank.pocnet.net/sheets/049/6/6AX5GT.pdf
Rectifier specs typically give max voltage, max current, min series resistance and max cap size. You may be able to slightly exceed one of these if you keep well within all the rest.
so this means that a resistor should be added in series to the plate if higher values are used?
Not that I plan on using a higher value... just trying to understand.
You can maintain a low value for the first cap in the filter, then place an inductor and a second cap as great as you want, while it can support the rectified voltage. this way you can lower the ripple at the power supply to negligible values, without damaging or overloading the rectifier.
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