Re: CIRCLOTRON...
Frank highjacking a thread?? I refuse to believe it!!
fdegrove said:Anyways, I feel we're threadjacking...well, that's how most people would see it I presume.
Frank highjacking a thread?? I refuse to believe it!!
Hi Frank,
Browsing old threads is a good thing, one never knows where interesting nuggets of information might pop up
Questions:
* That 35W operating point - what current/voltage does that consist of? I'm sure that'll also change the bias voltage, thus changing the requirements from the driver stage too?
* Compared to the more conventional 15W (60mA, 250V) operating point, how much would this shorten the life of the tube by? Any rough (or accurate) information?
* How does the sound of the tube change at this higher dissipation?
Thanks,
Saurav
Browsing old threads is a good thing, one never knows where interesting nuggets of information might pop up
P.S. I pushed the Sovtek 2A3 to above 40W and they accepted it graciously...
Before anyone asks I'm running them at 35W now and I'm very happy with the results....
Questions:
* That 35W operating point - what current/voltage does that consist of? I'm sure that'll also change the bias voltage, thus changing the requirements from the driver stage too?
* Compared to the more conventional 15W (60mA, 250V) operating point, how much would this shorten the life of the tube by? Any rough (or accurate) information?
* How does the sound of the tube change at this higher dissipation?
Thanks,
Saurav
Hi,
Saurav,
That would be 90mA @ 400VDC.
Yes, you'd better have a driver that can deliver the goods.
Roughly by a factor of two...not that I care much about that.
Don't know whether its' accurate, the tubes are rather too young to be able to forward more accurate predictions.
Pretty powerful for such a smal tube IMHO.Yummie...
Hi Sjef,
At the asking price it SHOULD a 300B and it could ...saves on tooling but then their 2A3 should show up on the plotter as a 300B...Anyone plotted one against the other?
And, they'd have to sound the same too, something 300Bs and 2A3s normally do not.
Either way it's a way overpriced tube which I won't even consider buying...there are still so many other fine sleepers around that I'd be building with before.
Cheers,
Saurav,
That 35W operating point - what current/voltage does that consist of? I'm sure that'll also change the bias voltage, thus changing the requirements from the driver stage too?
That would be 90mA @ 400VDC.
Yes, you'd better have a driver that can deliver the goods.
Compared to the more conventional 15W (60mA, 250V) operating point, how much would this shorten the life of the tube by? Any rough (or accurate) information?
Roughly by a factor of two...not that I care much about that.
Don't know whether its' accurate, the tubes are rather too young to be able to forward more accurate predictions.
How does the sound of the tube change at this higher dissipation?
Pretty powerful for such a smal tube IMHO.Yummie...
Hi Sjef,
At the asking price it SHOULD a 300B and it could ...saves on tooling but then their 2A3 should show up on the plotter as a 300B...Anyone plotted one against the other?
And, they'd have to sound the same too, something 300Bs and 2A3s normally do not.
Either way it's a way overpriced tube which I won't even consider buying...there are still so many other fine sleepers around that I'd be building with before.
Cheers,
That would be 90mA @ 400VDC.
So that's about 50% over the current rating. The cathode can actually supply 90mA... interesting.
Yes, you'd better have a driver that can deliver the goods.
Do you think my CCS'd ECC99 would be up to that task?
Roughly by a factor of two...not that I care much about that.
So... that means the new life expectancy would be how long?
Don't know whether its' accurate, the tubes are rather too young to be able to forward more accurate predictions.
I was searching for more info on this today, and that seemed to be the consensus I came up against - just not enough information available to form a statistically significant opinion.
Hi,
Certainly.
Persackly...
Not that I did any research on that aspect, I usually change all powertubes every two to three years and keep them as spares for whenever one decides to go south which is extremely rare.
Cheers and happy building,
Do you think my CCS'd ECC99 would be up to that task?
Certainly.
I was searching for more info on this today, and that seemed to be the consensus I came up against - just not enough information available to form a statistically significant opinion.
Persackly...
Not that I did any research on that aspect, I usually change all powertubes every two to three years and keep them as spares for whenever one decides to go south which is extremely rare.
Cheers and happy building,
Hot 2A3
Frank,
Is it safe to use autobias when running the 2A3's so hot ?
Jim
Frank,
That would be 90mA @ 400VDC
Is it safe to use autobias when running the 2A3's so hot ?
Jim
Hi,
Jim,
I haven't had any problems over the past five years.
Cheers,
Jim,
Is it safe to use autobias when running the 2A3's so hot ?
I haven't had any problems over the past five years.
Cheers,
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