BC550C/BC560C (2SA970/2SC2240) are suitable for both stages if the rail supply voltages are +/-35V and cascode collector current is 2 to 5mA, so to keep them safe from Vce-max and power dissipation point of view.
If supply voltages are higher I recommend BF471/BF472, 2SA1478/2SC3788 or similar TO-126 case high bandwidth transistors.
Please note that the pin config of 2SA970/2SC2240 is different to BC550C/560C you cannot drop one in place of the other.
Nico
The 2SA and 2SC parts look like the best, in terms of voltage and Hfe linearity over a wider range. Looks like mass quantities available on e-bay. So much so, that one wonders if they are genuine (don't need to be Toshiba mnf, if they have the same performance). Anyone with experience?
Sheldon
Yes that's the one I pushed hard
Mhmm you think an all mosfet output, drivers and output's? Nice one too.
Nico you are my friend, no hard feelings at all.
We are together in this project and stating out such detail is good for everyone as potential builders. We all have to be precise at details.
Nano Diamond Transistors, Operate in Vacuum - Better Than Tubes?
" DIAMOND TRANSISTORS "
From the txt . . .
here: http://news.vanderbilt.edu/2011/08/nanodiamond/
This transmission efficiency is also one reason why the new devices can run on very small amounts of electrical current. Another is that diamond is the best electron emitter in the world so it doesn’t take much energy to produce strong electron beams. “We think we can make devices that use one tenth the power of the most efficient silicon devices,” said Davidson.
The design is also largely immune to radiation damage. Radiation disrupts the operation of transistors by inducing unwanted charge in the silicon, causing an effect like tripping the circuit breaker in your home. In the nanodiamond device, on the other hand, the electrons flow through vacuum so there is nothing for energetic particles to disrupt. If the particles strike the nanodiamond anode or cathode, the impact is limited to a small fluctuation in the electron flow, not complete disruption, as is the case with silicon devices.
Scanning electron microscope image of a nanodiamond transistor. (Davidson Lab)
“When I read about the problems at the Fukushima power plant after the Japanese tsunami, I realized that nanodiamond circuits would be perfect for failsafe circuitry in nuclear reactors,” Davidson said. “It wouldn’t be affected by high radiation levels or the high temperatures created by the explosions.”
Nanodiamond devices can be manufactured by processes that the semiconductor industry currently uses. The one exception is the requirement to operate in vacuum, which would require some modification in the packaging process. Currently, semiconductor chips are sealed in packages filled with an inert gas like argon or simply encapsulated in plastic, protecting them from chemical degradation. Davidson and his colleagues have investigated the packaging process and have found that the metallic seals used in military-grade circuitry are strong enough to hold an adequate vacuum for centuries.
Better Days also for Audio are coming ?
Watch webcast of Davidson talking about the first nanodiamond vacuum emitter device logic circuits.
Cheers
A.
" DIAMOND TRANSISTORS "
From the txt . . .
here: http://news.vanderbilt.edu/2011/08/nanodiamond/
This transmission efficiency is also one reason why the new devices can run on very small amounts of electrical current. Another is that diamond is the best electron emitter in the world so it doesn’t take much energy to produce strong electron beams. “We think we can make devices that use one tenth the power of the most efficient silicon devices,” said Davidson.
The design is also largely immune to radiation damage. Radiation disrupts the operation of transistors by inducing unwanted charge in the silicon, causing an effect like tripping the circuit breaker in your home. In the nanodiamond device, on the other hand, the electrons flow through vacuum so there is nothing for energetic particles to disrupt. If the particles strike the nanodiamond anode or cathode, the impact is limited to a small fluctuation in the electron flow, not complete disruption, as is the case with silicon devices.
Scanning electron microscope image of a nanodiamond transistor. (Davidson Lab)
“When I read about the problems at the Fukushima power plant after the Japanese tsunami, I realized that nanodiamond circuits would be perfect for failsafe circuitry in nuclear reactors,” Davidson said. “It wouldn’t be affected by high radiation levels or the high temperatures created by the explosions.”
Nanodiamond devices can be manufactured by processes that the semiconductor industry currently uses. The one exception is the requirement to operate in vacuum, which would require some modification in the packaging process. Currently, semiconductor chips are sealed in packages filled with an inert gas like argon or simply encapsulated in plastic, protecting them from chemical degradation. Davidson and his colleagues have investigated the packaging process and have found that the metallic seals used in military-grade circuitry are strong enough to hold an adequate vacuum for centuries.
Better Days also for Audio are coming ?
Watch webcast of Davidson talking about the first nanodiamond vacuum emitter device logic circuits.
Cheers
A.
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