raypsi wrote:
On Dec 29, 1:21 pm, "Tio Pedro" wrote:
Anyone really, really old dudes on hear who can advise
on how much RF power an 01 can handle? Can it drive
a 45 power stage?

Pete

Hey OM
How old is a really really old dude? Is that like Methuselah?
Although Ima really old fart. I think there would be to much gas in
that tube for you to use it for anything but a gas regulator tube. I
bet it would fire up at 150 VDC wit that nice blueish glow.

73 OM
n8zu
The 01A was considered a 'hard vacuum' tube, the '00 was a 'vapor' tube,
or soft vacuum tube. The only reason that the '00 was even made was
because many 'old timers' (at the time that the '00 came out) remembered
using the ORIGINAL DeForest Audio which was a soft vacuum tube. By
carefully adjusting the plate and filament voltages a very sensitive
operating point could be found. The tube was probably acting as a
thyratron at this point, on the verge of super-conduction. The '00
could also operate this way, but since it's manufacture was more
controlled than the original Audion the operating point was well known.

Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.

"ken scharf" wrote in message
...
Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.

Will it have enough output to drive a 245?

Tio Pedro wrote:
"ken scharf" wrote in message
...
Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.

Will it have enough output to drive a 245?


I'm sure it will drive a neutralized 245 to provide some gain.
You might not get enough drive for full power output from the 245.
(even if the 245 was run in class A, which requires NO driving power
you would still see SOME power gain).

On Dec 30, 2:54*pm, ken scharf wrote:
Tio Pedro wrote:
"ken scharf" wrote in message
...
* Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. *It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.

Will it have enough output to drive a 245?

I'm sure it will drive a neutralized 245 to provide some gain.
You might not get enough drive for full power output from the 245.
(even if the 245 was run in class A, which requires NO driving power
you would still see SOME power gain).

Hmmmm...You think class A at RF requires no driving power??

Cheers,
Tom

K7ITM wrote:
On Dec 30, 2:54 pm, ken scharf wrote:
Tio Pedro wrote:
"ken scharf" wrote in message
...
Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.
Will it have enough output to drive a 245?
I'm sure it will drive a neutralized 245 to provide some gain.
You might not get enough drive for full power output from the 245.
(even if the 245 was run in class A, which requires NO driving power
you would still see SOME power gain).

Hmmmm...You think class A at RF requires no driving power??

Cheers,
Tom
Only voltage, no current.
Of course some power gets wasted since resistance isn't zero and some
heat is generated in the coils, etc. I guess there is some power factor
in the grid / cathode capacitance etc. The input impedance of the '45
in class A SHOULD BE infinite. It isn't, but it IS VERY HIGH. So
except for losses, no driving power, only voltage.

On Dec 31 2008, 7:16*pm, ken scharf
wrote:
K7ITM wrote:
On Dec 30, 2:54 pm, ken scharf wrote:
Tio Pedro wrote:
"ken scharf" wrote in message
. ..
* Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. *It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.
Will it have enough output to drive a 245?
I'm sure it will drive a neutralized 245 to provide some gain.
You might not get enough drive for full power output from the 245.
(even if the 245 was run in class A, which requires NO driving power
you would still see SOME power gain).

Hmmmm...You think class A at RF requires no driving power??

Cheers,
Tom

Only voltage, no current.
Of course some power gets wasted since resistance isn't zero and some
heat is generated in the coils, etc. *I guess there is some power factor
in the grid / cathode capacitance etc. *The input impedance of the '45
in class A SHOULD BE infinite. *It isn't, but it IS VERY HIGH. *So
except for losses, no driving power, only voltage.

OK, to get an _accurate_ answer with respect to grid driving power,
you need to account for the effects of the electrons going from
cathode to plate as they pass by the grid. At high enough frequency,
this becomes significant. This is quite apart from losses in elements
external to the tube. One reference about this is Terman's "Radio
Engineers' Handbook, section 4, paragraph 9. But just consider that
it takes a certain amount of _energy_ to push those electrons around
and control them, even if they don't actually ever come in contact
with the grid.

Cheers,
Tom

On Jan 1, 1:29 pm, K7ITM wrote:
On Dec 31 2008, 7:16 pm, ken scharf
wrote:



K7ITM wrote:
On Dec 30, 2:54 pm, ken scharf wrote:
Tio Pedro wrote:
"ken scharf" wrote in message
. ..
Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.
Will it have enough output to drive a 245?
I'm sure it will drive a neutralized 245 to provide some gain.
You might not get enough drive for full power output from the 245.
(even if the 245 was run in class A, which requires NO driving power
you would still see SOME power gain).

Hmmmm...You think class A at RF requires no driving power??

Cheers,
Tom

Only voltage, no current.
Of course some power gets wasted since resistance isn't zero and some
heat is generated in the coils, etc. I guess there is some power factor
in the grid / cathode capacitance etc. The input impedance of the '45
in class A SHOULD BE infinite. It isn't, but it IS VERY HIGH. So
except for losses, no driving power, only voltage.

OK, to get an _accurate_ answer with respect to grid driving power,
you need to account for the effects of the electrons going from
cathode to plate as they pass by the grid. At high enough frequency,
this becomes significant. This is quite apart from losses in elements
external to the tube. One reference about this is Terman's "Radio
Engineers' Handbook, section 4, paragraph 9. But just consider that
it takes a certain amount of _energy_ to push those electrons around
and control them, even if they don't actually ever come in contact
with the grid.

Cheers,
Tom

Hey OM
I guess it's so ez to forget about the law. The law of conservation of
energy.
You can't create or destroy energy. Physics 101.

73 OM
n8zu

"Tio Pedro" wrote in message
...

"ken scharf" wrote in message
...
Even with it's 'hard vacuum' the 01 didn't have as good a 'getter' as
later tubes and would arc over with more than 130 volts or so. It was
used as a transmitter before the type 202 tube became widely available,
but was a QRP thing, less than a watt input.

Will it have enough output to drive a 245?
I doubt it very seriously. I suppose if perfection was achieved in matching
the 01's output to the 245's grid was possible (I, for one cannot do it),
the losses would be enough to tickle it into the beginning of class C.

Ken's idea of going to class A might work, but the 245 would be running
in a very inefficient mode. There is one website showing a couple of
45's running in AB2 (how do you make a sub 2?) . Another website
has some interesting stuff with 245 chatter...... (you may have already
seen it, but just in case..........

http://www.antiquewireless.org/otb/29amp.htm

Old Chief Lynn, W7LTQ and a couple commercials

Lynn wrote:



Ken's idea of going to class A might work, but the 245 would be running
in a very inefficient mode.


I can't fathom a 20s xmtr circuit running the PA in Class A.

-ex

Lynn wrote:

"Tio Pedro" wrote in message
...

"ken scharf" wrote in message
...
Even with it's 'hard vacuum' the 01 didn't have as good a 'getter'
as later tubes and would arc over with more than 130 volts or so. It
was used as a transmitter before the type 202 tube became widely
available, but was a QRP thing, less than a watt input.

Will it have enough output to drive a 245?
I doubt it very seriously. I suppose if perfection was achieved in matching
the 01's output to the 245's grid was possible (I, for one cannot do it),
the losses would be enough to tickle it into the beginning of class C.

Ken's idea of going to class A might work, but the 245 would be running
in a very inefficient mode. There is one website showing a couple of
45's running in AB2 (how do you make a sub 2?) . Another website
has some interesting stuff with 245 chatter...... (you may have already
seen it, but just in case..........

http://www.antiquewireless.org/otb/29amp.htm

Old Chief Lynn, W7LTQ and a couple commercials
Actually AB1 would be better. My point was that you don't need driving
power until you start drawing grid current. As long as the final
doesn't draw grid current you are not loading down the oscillator tube.
The question was would the 01A be able to drive a '45. My answer is
yes, but probably not to full output....meaning you won't be able to
supply much grid current.