Guest
http://file2.answcdn.com/answ-cld/image/upload/h_320,c_fill,g_face:center,q_60,f_jpg/v1401492366/pq8ch6utdabn6r2ybozq.png
Cheers,
Michael
Cheers,
Michael
C
Cydrome Leader
Guest
mrdarrett@gmail.com wrote:
> http://file2.answcdn.com/answ-cld/image/upload/h_320,c_fill,g_face:center,q_60,f_jpg/v1401492366/pq8ch6utdabn6r2ybozq.png
Ha.
> http://file2.answcdn.com/answ-cld/image/upload/h_320,c_fill,g_face:center,q_60,f_jpg/v1401492366/pq8ch6utdabn6r2ybozq.png
Ha.
Guest
On Wednesday, March 25, 2015 at 10:10:49 AM UTC-7, Cydrome Leader wrote:
What exactly is the point of the coil labeled H, anyway? And why is it given a (+) symbol?
What exactly is the point of the coil labeled H, anyway? And why is it given a (+) symbol?
Guest
On Wednesday, March 25, 2015 at 11:56:22 AM UTC-7, Pimpom wrote:
Oh! Cool! Thanks!
Oh! Cool! Thanks!
Guest
On Wednesday, March 25, 2015 at 1:32:12 PM UTC-7, John Larkin wrote:
Unfortunately a lot of knowledge has been lost, it's true. Didn't a Soviet fighter pilot defect a few decades ago, taking a Soviet supersonic jet with him, with all sorts of EMP-proof vacuum tube electronic controls?
Michael
Unfortunately a lot of knowledge has been lost, it's true. Didn't a Soviet fighter pilot defect a few decades ago, taking a Soviet supersonic jet with him, with all sorts of EMP-proof vacuum tube electronic controls?
Michael
P
Pimpom
Guest
<mrdarrett@gmail.com> wrote in message
news:d8bf1339-b476-436b-b3c8-772777a67bca@googlegroups.com...
The diagram represents a vacuum tube rectifier circuit. Coil H
supplies heating power to the rectifier's filament which acts as
a source of electrons and therefore as the cathode. The + symbol
marks the positive output rail.
news:d8bf1339-b476-436b-b3c8-772777a67bca@googlegroups.com...
The diagram represents a vacuum tube rectifier circuit. Coil H
supplies heating power to the rectifier's filament which acts as
a source of electrons and therefore as the cathode. The + symbol
marks the positive output rail.
J
John Larkin
Guest
On Wed, 25 Mar 2015 13:15:44 -0700 (PDT), mrdarrett@gmail.com wrote:
You youngsters have clean forgotton how toobs work. "H" is for
"heater."
--
John Larkin Highland Technology, Inc
picosecond timing laser drivers and controllers
jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com
You youngsters have clean forgotton how toobs work. "H" is for
"heater."
--
John Larkin Highland Technology, Inc
picosecond timing laser drivers and controllers
jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com
T
Tim Wescott
Guest
On Tue, 24 Mar 2015 10:30:06 -0700, mrdarrett wrote:
That's a sad rectifier tube, not a sad inductor. It's sad because it
knows that there's young whippersnappers out there that can't recognize
the schematic symbol for a rectifier tube any more.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
That's a sad rectifier tube, not a sad inductor. It's sad because it
knows that there's young whippersnappers out there that can't recognize
the schematic symbol for a rectifier tube any more.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
P
Pimpom
Guest
"Tim Wescott" <seemywebsite@myfooter.really> wrote in message
news:FaWdnVuIYLv0tY7InZ2dnUU7-fWdnZ2d@giganews.com...
although I'm well into that age - saw my old portable mechanical
typewriter and asked me how it's connected to a computer.
news:FaWdnVuIYLv0tY7InZ2dnUU7-fWdnZ2d@giganews.com...
The other day, my brother's grandson - don't have one myself yet
although I'm well into that age - saw my old portable mechanical
typewriter and asked me how it's connected to a computer.
P
Pimpom
Guest
"John Larkin" <jlarkin@highlandtechnology.com> wrote in message
news:qn66ha9679e0cupviamjitsccvssh4vfm5@4ax.com...
conduct, I usually begin with vacuum tubes. Besides making the
students appreciate how technology developed, I feel that
visualizing a stream of tiny electron balls - classical physics
is good enough for the purpose - flying through a vacuum from
cathode to anode gives them a clear mental image of how it all
works. It's further useful at the next step: control of the
current flow with a grid. It also has a kind of elegance to it. I
go into the maths later.
news:qn66ha9679e0cupviamjitsccvssh4vfm5@4ax.com...
When I start into active devices in the training classes I
conduct, I usually begin with vacuum tubes. Besides making the
students appreciate how technology developed, I feel that
visualizing a stream of tiny electron balls - classical physics
is good enough for the purpose - flying through a vacuum from
cathode to anode gives them a clear mental image of how it all
works. It's further useful at the next step: control of the
current flow with a grid. It also has a kind of elegance to it. I
go into the maths later.
Guest
>"That gave us electron flow and convencional current flow to remember. "
Us regular critters can generally forget about which way the electrons go in a circuit. With complementary devices it almost doesn't matter at all.
However there is a reason thaty silicon NPN transistors are better and germaniun PNP transistors were better. That is more on a molecular level and that's the job of people who work at Onsemi and the like.
Us regular critters can generally forget about which way the electrons go in a circuit. With complementary devices it almost doesn't matter at all.
However there is a reason thaty silicon NPN transistors are better and germaniun PNP transistors were better. That is more on a molecular level and that's the job of people who work at Onsemi and the like.
R
Ralph Mowery
Guest
"Pimpom" <pimpom@invalid.invalid> wrote in message
news:mf0c6r$p1t$1@news.albasani.net...
I was either lucky or unlucky that when I went to tech school in 1970 that
tubes and transistors were both being taught. Had to learn both types of
circuits.
Not sure who, thinking Ben Franklin that got the electron flow backwards.
That gave us electron flow and convencional current flow to remember.
news:mf0c6r$p1t$1@news.albasani.net...
I was either lucky or unlucky that when I went to tech school in 1970 that
tubes and transistors were both being taught. Had to learn both types of
circuits.
Not sure who, thinking Ben Franklin that got the electron flow backwards.
That gave us electron flow and convencional current flow to remember.
Guest
Did you tell him about its excellent hacker-proof properties?
T
Tim Wescott
Guest
On Thu, 26 Mar 2015 09:41:08 -0700, jurb6006 wrote:
I thought that the only driver behind the Germanium PNP thing was because
point-contact transistors pretty much have to be PNP due to the physics of
strained crystals.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
I thought that the only driver behind the Germanium PNP thing was because
point-contact transistors pretty much have to be PNP due to the physics of
strained crystals.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
R
Ralph Mowery
Guest
"Tim Wescott" <seemywebsite@myfooter.really> wrote in message
news:b_qdnX51r7i0V4jInZ2dnUU7-TOdnZ2d@giganews.com...
negative ground system.
news:b_qdnX51r7i0V4jInZ2dnUU7-TOdnZ2d@giganews.com...
I don't know about which is beter,but probably the big reason is to have a
negative ground system.
P
Pimpom
Guest
"Tim Wescott" <seemywebsite@myfooter.really> wrote in message
news:b_qdnX51r7i0V4jInZ2dnUU7-TOdnZ2d@giganews.com...
Ge transistors had lower Vce(sat) than Si. This and the lower Vbe
were significant in low-voltage applications. Ge power
transistors also had better gain linearty as we approach a
device's max current ratings.
news:b_qdnX51r7i0V4jInZ2dnUU7-TOdnZ2d@giganews.com...
Some impressions I've retained from some 40+ years ago -
Ge transistors had lower Vce(sat) than Si. This and the lower Vbe
were significant in low-voltage applications. Ge power
transistors also had better gain linearty as we approach a
device's max current ratings.
P
Pimpom
Guest
"Tim Wescott" <seemywebsite@myfooter.really> wrote in message
news:b_qdnX51r7i0V4jInZ2dnUU7-TOdnZ2d@giganews.com...
Ge transistors had lower Vce(sat) than Si. This and the lower Vbe
were significant in low-voltage applications. Ge power
transistors also had better gain linearty as we approach a
device's max current ratings.
news:b_qdnX51r7i0V4jInZ2dnUU7-TOdnZ2d@giganews.com...
Some impressions I've retained from some 40+ years ago -
Ge transistors had lower Vce(sat) than Si. This and the lower Vbe
were significant in low-voltage applications. Ge power
transistors also had better gain linearty as we approach a
device's max current ratings.
T
Tim Wescott
Guest
On Fri, 27 Mar 2015 17:55:11 -0400, Ralph Mowery wrote:
NPN silicon transistors definitely tend to be better, for the same reason
N-channel MOSFETs do: electron mobility in N-type silicon is better than
hole mobility in P-type.
I'm pretty sure the same thing applies to germanium.
The very first transistors were point-contact type, though, which worked
because when you stress lightly-doped N-type germanium it becomes P-type.
However, it only works for PNP transistors.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
NPN silicon transistors definitely tend to be better, for the same reason
N-channel MOSFETs do: electron mobility in N-type silicon is better than
hole mobility in P-type.
I'm pretty sure the same thing applies to germanium.
The very first transistors were point-contact type, though, which worked
because when you stress lightly-doped N-type germanium it becomes P-type.
However, it only works for PNP transistors.
--
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
J
jfeng@my-deja.com
Guest
On Saturday, March 28, 2015 at 10:01:50 PM UTC-7, Tim Wescott wrote: