I am looking for a tube replacement for this transistor:

http://www1.jaycar.com.au/images_uploaded/MJL21193.PDF

I realize the specs may be somewhat different, but perhaps you can
point me in the right direction.

A tube which can handle high voltage spikes and switches like this
(bipolar) transistor. Can someone help me source this. Thanks for any
help you can provide.

Please email to dane [AT] edensanctuary.com

Thanks.

Your pdf file characterises two transistors, one NPN and one PNP.
Which one do you have in mind?

K. L.

wildfire wrote:
I am looking for a tube replacement for this transistor:

http://www1.jaycar.com.au/images_uploaded/MJL21193.PDF

I realize the specs may be somewhat different, but perhaps you can
point me in the right direction.

A tube which can handle high voltage spikes and switches like this
(bipolar) transistor. Can someone help me source this. Thanks for any
help you can provide.

Please email to dane [AT] edensanctuary.com

Thanks.

"wildfire" wrote in message
ups.com...
I am looking for a tube replacement for this transistor:

http://www1.jaycar.com.au/images_uploaded/MJL21193.PDF

I realize the specs may be somewhat different, but perhaps you can
point me in the right direction.

A tube which can handle high voltage spikes and switches like this
(bipolar) transistor. Can someone help me source this. Thanks for any
help you can provide.

Please email to dane [AT] edensanctuary.com

**A 16 Amp tube? Heheh. I hope you've got VERY deep pockets. Bottom line:
There are some things tubes cannot do, for any sane amount of cash. Handling
lots of current, at low to medium Voltages, is not one of them.

If you're just switching current, look at a MOSFET. Much more economical.


--
Trevor Wilson
www.rageaudio.com.au

"wildfire"

I am looking for a tube replacement for this transistor:

http://www1.jaycar.com.au/images_uploaded/MJL21193.PDF


** Huh ???

What the hell do you want that for ???


I realize the specs may be somewhat different, but perhaps you can
point me in the right direction.


** The nearest nut house will do.


A tube which can handle high voltage spikes and switches like this
(bipolar) transistor.


** You want a switch or an amplifier.

That device is a linear amplifier.


Can someone help me source this.


** Get real.


Please email to dane [AT] edensanctuary.com



** So he lives in a nut house already.




............. Phil

On 1 Mar 2005 14:21:13 -0800, "wildfire" wrote:

I am looking for a tube replacement for this transistor:

http://www1.jaycar.com.au/images_uploaded/MJL21193.PDF

Are you crazy? ARE YOU CRAZY?? 16 amps?!?!?

what the hell for?

I realize the specs may be somewhat different, but perhaps you can
point me in the right direction.

How about Alpha Proxima?

A tube which can handle high voltage spikes and switches like this

Almost any tube made can handle 250v.. and a microwave tube can switch pretty
fast.... what current do you need?? 1/10 amp is easy... any more is hard....
But for a few thousand dollars you may be able to get a used transmitter tube
that can handle it... shouldn't be too much bigger then your bathroom.... It
does have it's advantages, you can go inside it and clean the cathode... don't
forget to turn off the vacuum pump!

(bipolar) transistor. Can someone help me source this. Thanks for any
help you can provide.

I don't really have the 3 years it would take to train you...


Please email to dane [AT] edensanctuary.com

Thanks.

"Trevor Wilson" wrote in message
...
**A 16 Amp tube? Heheh. I hope you've got VERY deep pockets.

Well, I don't know about that. A couple EL519's or 6KD6s (or whatever's the
biggest sweep out there) can pass a good couple of amperes, depending on
screen voltage. Count on a few hundred watts heater dissipation. You will
have difficulty matching the saturation voltage, though.

An alternative would be to use a higher impedance circuit, one which better
matches the performance of the tubes (just as the transistors had a
relatively matched load). This is usually done with a transformer.
Complementary parts (emitter follower output) are replaced with balanced
circuitry (PP cathode follower, or plate follower with loop NFB).

250V 16A 200W transistors correspond to say, 1000V Vpmax, 2A Ik, 50 to 200W
Pd. (Particularly with plate cap types, plate voltage ratings are uselessly
high (a 6LQ6 can handle 7.5kV peak), Ik is about the same as Ie, and Pd is
continuous, not peak. Tubes are generally far more rugged and aside from a
melted screen, you'll have to _work_ to get the smoke out...er, in.)

Tim

--
"California is the breakfast state: fruits, nuts and flakes."
Website: http://webpages.charter.net/dawill/tmoranwms

What are you actually thinking of using this for? If it's for some rational
use (i.e. not audio or something like that), use silicon. It's much more
sane.

As has already been implied, valves are generally high impedance devices
(high voltage, low current). Though I suppose you could use twenty or so
7241s if you can get your hands on them and aren't worried about 945W of
heater power! Actually, if you find any valves that can pass 16A at
reasonable anode voltages you will surely be building an OTL!

Jason

"wildfire" wrote in message
ups.com...
I am looking for a tube replacement for this transistor:

http://www1.jaycar.com.au/images_uploaded/MJL21193.PDF

I realize the specs may be somewhat different, but perhaps you can
point me in the right direction.

A tube which can handle high voltage spikes and switches like this
(bipolar) transistor. Can someone help me source this. Thanks for any
help you can provide.

Please email to dane [AT] edensanctuary.com

Thanks.

"Tim Williams.

Well, I don't know about that.


** You do not "know about" any damn thing you smelly, pimply faced turd.

You are one pig ignorant, colossally arrogant, flagrantly publicly
masturbating, absolute bloody moron.

Then there is your bad side.






............... Phil

wildfire wrote:

I am looking for a tube replacement for this transistor:

http://www1.jaycar.com.au/images_uploaded/MJL21193.PDF

I realize the specs may be somewhat different, but perhaps you can
point me in the right direction.

A tube which can handle high voltage spikes and switches like this
(bipolar) transistor. Can someone help me source this. Thanks for any
help you can provide.

Please email to dane [AT] edensanctuary.com

Thanks.

I just built a 300 w/channel stereo amp using lots of the above trannies
plus its complementary mate.

There *are no tubes* that could replace the MJL21194/94
These bjts have current ability of about 16 Amps rated.
The only tube able to do that is a monster transmitting tube but
you only get that sort of current in conjunction with an applied
10,000 volts in the supply.

Forget about subbing tubes for power transistors.

Be a real man and build a real tube amp.

Patrick Turner.

Thanks for all your feedback. The amp spec is not important. It can be
of a low-tube amp nature. What is needed is a power tube that can
handle these general specs...

1) 1000-2000 volts
2) lowest heat generation
3) switching capability at least 100 times a second (clean switching
like a transistor)

This is not being used in an amp, but for a science project.

"wildfire"

Thanks for all your feedback. The amp spec is not important. It can be
of a low-tube amp nature. What is needed is a power tube that can
handle these general specs...

1) 1000-2000 volts
2) lowest heat generation
3) switching capability at least 100 times a second (clean switching
like a transistor)

This is not being used in an amp, but for a science project.


** Your question is purest gobbledegook.

Transistors and mosfets make near perfect switches - valves do not.

You must come up with a specification for the switching performance needed
that is not just a bunch of hand waving - seems you have no capacity to do
so.

Find someone to help you.





............ Phil

Hi,

There are probably many valves that can satisfy your critera (as long as
they aren't called on to pass too much current), but Usenet isn't really the
place to ask. You can only ignore the trolls for so long until they make
your blood boil.

On your second criterion, basically all valves will waste a few watts in
heater/filament power - they will get quite warm on their own without even
drawing any cathode current. Types capable of passing more current will
require more heater power.

Might I suggest posting your question somewhere like "The Geek Zone"
http://geek.scorpiorising.ca/cgi-bin/yabb/YaBB.pl. You are more likely to
get constructive comments there, and without the abuse.

Jason


"wildfire" wrote in message
ups.com...
Thanks for all your feedback. The amp spec is not important. It can be
of a low-tube amp nature. What is needed is a power tube that can
handle these general specs...

1) 1000-2000 volts
2) lowest heat generation
3) switching capability at least 100 times a second (clean switching
like a transistor)

This is not being used in an amp, but for a science project.

"Jason R." = masturbating imbecile

There are probably many valves that can satisfy your critera


** Really Jason ??

Name one readily available and moderate cost tube that can switch like a
POWER transistor. That means the "on state " voltage is less than 2 volts
while the "on state" current is several amps.

The ****wit OP cannot describe what he needs at all - so NO-ONE can give
him advice.

You just gave him a fool's advice.





............ Phil

Phil,

I wrote:

"Usenet isn't really the place to ask. You can only ignore the trolls for so
long until they make your blood boil."

Why, thankyou for firming my conviction.

Jason

"Jason R." = another, slimy autistic POS tube ******

Phil,

Why, thankyou for firming my conviction.



** Err - what were you convicted of - chronic self abuse ????


I repeat ....

Name one readily available and moderate cost tube that can switch like a
POWER transistor. That means the "on state " voltage is less than 2 volts
while the "on state" current is several amps.

The ****wit OP cannot describe what he needs at all - so NO-ONE can give
him advice.

You just gave him a fool's advice.





............ Phil

Phil,

Frankly, your posts on this board are so maliciously worded that they are
not worthy of a reply, but against my better judgement:

It is true, he is being so vague that no one can truly recommend a suitable
valve. Note that it was stated that "the amp spec is not important", but we
can not read wildfire's mind as to how low a current handling capacity is
permissible - which is why I suggested that he open a discussion somewhere
else where everyone is treated in a more civil manner. If no valve can
satisfy his criteria, so be it - but it is no reason to hurl abuse.

Jason

"wildfire" wrote in message
ups.com...
: Thanks for all your feedback. The amp spec is not important. It can be
: of a low-tube amp nature. What is needed is a power tube that can
: handle these general specs...
:
: 1) 1000-2000 volts
: 2) lowest heat generation
: 3) switching capability at least 100 times a second (clean switching
: like a transistor)
:
: This is not being used in an amp, but for a science project.
:
The combination lowish heat generation - hi voltage capacity is not
something you'll find with tubes (if you need current, as well).
Maybe an IRFP50 [900V, 7A] is an option ? - it's about 7 dollars.
Good idea could be to check websites dedicated to Tesla - experiments.

Good luck,
Rudy

"Ruud Broens" wrote in message
...
:
: "wildfire" wrote in message
: ups.com...
: : Thanks for all your feedback. The amp spec is not important. It can be
: : of a low-tube amp nature. What is needed is a power tube that can
: : handle these general specs...
: :
: : 1) 1000-2000 volts
: : 2) lowest heat generation
: : 3) switching capability at least 100 times a second (clean switching
: : like a transistor)
: :
: : This is not being used in an amp, but for a science project.
: :
: The combination lowish heat generation - hi voltage capacity is not
: something you'll find with tubes (if you need current, as well).
: Maybe an IRFP50 [900V, 7A] is an option ? - it's about 7 dollars.
: Good idea could be to check websites dedicated to Tesla - experiments.
:
: Good luck,
: Rudy
:
btw, 2000V and shortly about 1.5 - 2 Amps should be possible with the 4CX350A;
filament is a 'modest' 6V 2.9 A requirement - it's on the german ebay , 69 euro's
for 2. The sockets, if ya can find them, will cost ya plenty, tho :-)

"Jason R." = a typical autistic puke


Frankly, your posts on this board are so maliciously worded that they are
.....


** Frankly Jason - the whole planet would be much the better off if you
had been aborted.

Mentally defective POS like you are a pox on the whole of civilisation.



It is true, he is being so vague that no one can truly recommend a
suitable valve.


** Which reveals that he is an autistic **** - just like you.



Note that it was stated that "the amp spec is not important", but we can
not read wildfire's mind ....


** Err - since, like you, he has not got one.



as to how low a current handling capacity is permissible - which is why I
suggested that he open a discussion somewhere else where everyone is
treated in a more civil manner.


* Sure - with dudes in white suits and in padded rooms.



If no valve can satisfy his criteria, so be it - but it is no reason to
hurl abuse.



** Asinine trolls like the "wildfire" just beg to be abused so they will
never come back.

The same applies to spew inducing ****s like you.






.................. Phil

"Jason R." wrote:

Phil,

I wrote:

"Usenet isn't really the place to ask. You can only ignore the trolls for so
long until they make your blood boil."

Why, thankyou for firming my conviction.

Jason

Sometimes Jason its hard to detect any difference between a fair
questioner and a troll.

The dude asked for a substitute for a heavy duty flat pack
power transistor.

There simply isn't any single tube which could be placed into a typical circuit
using the MJL21193/94 variety of transistor.
The transconductance required is approximately 30 amps/V,
so you'd need 3,000 EL34 tubes in parallel to achieve it.
And EL34 would NOT work real well with a rail voltage of say 100V.

If the dude wants to substitute the MJL21194/94 with tubes, he should
forget all ideas about some direct sub, and forget all about using a transistor
amp topology, and consider simply
using a tube amp design with an OPT, where the high output current of the power
bjt can be gained by several tubes in parallel with an OPT to
transform the tiny current and high voltage swing of the tube to
a low voltage swing at a high current.

It seems obvious to us who have been here for more than 5 minutes
that the original question was a silly one.
I hold no grudges against silly questions; more than one person
must wonder why he cannot plug in a tube instead of using a power transistor,
heck, they are both power devices.

In the fullness of time, I hope our original questioner comes to see
that his question cannot easily be answered.

Phil's attempt at boiling my blood has been entirely unsuccessful.

Patrick Turner.












vn

"Jason R." wrote:

Phil,

Frankly, your posts on this board are so maliciously worded that they are
not worthy of a reply, but against my better judgement:

It is true, he is being so vague that no one can truly recommend a suitable
valve. Note that it was stated that "the amp spec is not important", but we
can not read wildfire's mind as to how low a current handling capacity is
permissible - which is why I suggested that he open a discussion somewhere
else where everyone is treated in a more civil manner. If no valve can
satisfy his criteria, so be it - but it is no reason to hurl abuse.

Jason

Jason, it **is** possible to use tubes to replace transistors, but not
as drop in replacements, better to drop the idea of a transistor amp altogether

if one wants to use tubes, or explore exactly what one may have to do to
equal what the bjt does.

But one could use 375 x EL34 tubes all in parallel, and all hooked
up in an SE amp that would then draw 9,375 watts of plate power,
and produce 3,750 watts of class A SE audio power directly into a load of 8
ohms,
and without an OPT, and the anode V swing would be 173 vrms.
The current max would be 21.65 amps rms, about the same as a single power
transistor.
Gain would be about 26, far less than the power transistor, but somewhat
similar
to a power mosfet.
The rail voltage would have to be around 350v, or not nuch more than the
maximum
permissable + or - rails used in a typical high power SS amps.

The bandwidth using 375 EL34 without an OPT
would probably be up around many MHz, and controlling
RF oscillations would be a problem, but
I doubt the tubes would have any troubles switching their output current
quickly enough for
audio, and I would suggest square wave signals would look pretty decent in a
tube amp as suggested.

The miller effect in a pentode isn't too bad even with 375 in parallel;
this input miller capacitance can be easily overcome as it is with one pentode.

Frankly, why anyone would want to use hundreds of tubes as suggested
is a mystery, when the bjts or well selected mosfets would
provide audio at the +3,000 watt level in a perfectly suitable manner, and many
times
more efficiently, and at far lower distortion, bearing in mind
that really high power use is for PA, and most focused on rock and pop
where the sonics of the tubes will never ever make up for the appalling lack of
musical training
or talent demonstrated by most pop/rock artistes, even though they have
charisma, aura, khama, etc.
So we do get such artistes using tube amps on stage, but their sound is then
amped
up by SS, not tubes, to allow large numbers to enjoy the gig and damage their
hearing.

Patrick Turner.

"Patrick Turner"

But one could use 375 x EL34 tubes all in parallel...



** **** OFF YOU ASININE ****WIT !!!!!!!!








................... Phil

Phil Allison wrote:

"Patrick Turner"

But one could use 375 x EL34 tubes all in parallel...

** **** OFF YOU ASININE ****WIT !!!!!!!!

.................. Phil

I suggest you get a good night's sleep Phil.

Parading around the Internet issuing Nazi type instructions
never did make you look real intelligent.

Patrick Turner.

How about he

http://tinyurl.com/6xbh9

"Patrick Turner"

Phil Allison wrote:


But one could use 375 x EL34 tubes all in parallel...

** **** OFF YOU ASININE ****WIT !!!!!!!!



I suggest you get a good night's sleep Phil.


** I suggest you top yourself now.



Parading around the Internet issuing Nazi type instructions...


** More Turneroid paranoid, ****wit bull****.





................. Phil

"Patrick Turner" wrote in message
...
Sometimes Jason its hard to detect any difference between a fair
questioner and a troll. [snip]
It seems obvious to us who have been here for more than 5 minutes
that the original question was a silly one.

True, it was a silly question to ask for a direct replacement for an
MJL21193.

Phil's attempt at boiling my blood has been entirely unsuccessful.

You clearly have thick skin, but I can't help thinking that much of your
insight is being wasted around here. It would be much better appreciated
somewhere else like diyAudio
http://www.diyaudio.com/forums/forum...p?s=&forumid=5

"Jason R." = pathetic jerk off

"Patrick Turner" = criminal & lunatic

Sometimes Jason its hard to detect any difference between a fair
questioner and a troll.


** Impossible for those who are trolls themselves.


It seems obvious to us who have been here for more than 5 minutes
that the original question was a silly one.

True, it was a silly question to ask for a direct replacement for an
MJL21193.

Phil's attempt at boiling my blood has been entirely unsuccessful.

You clearly have thick skin,


** The Turneroid has a colossally thick hide - all the planet's
rhinoceros are jealous.



but I can't help thinking that much of your insight is being wasted around
here.


** The Turneroid had ZERO insight - he is mentally defective.

He is an autistic cretin.

Plus a fool and a public menace.



............ Phil

"Jason R." wrote:

"Patrick Turner" wrote in message
...
Sometimes Jason its hard to detect any difference between a fair
questioner and a troll. [snip]
It seems obvious to us who have been here for more than 5 minutes
that the original question was a silly one.

True, it was a silly question to ask for a direct replacement for an
MJL21193.

Phil's attempt at boiling my blood has been entirely unsuccessful.

You clearly have thick skin, but I can't help thinking that much of your
insight is being wasted around here. It would be much better appreciated
somewhere else like diyAudio
http://www.diyaudio.com/forums/forum...p?s=&forumid=5

The trouble with the plethera of forums around is that they don't
seen to set themselves up to work like the bulletin board
style of posting listings like it is here at rat.

They are usually awkward and slow to use,
and require some special browser; ie, for example not
all forums work with Netscape 4.7, and operate only
in plain text.
Simple is best with forums, the less fancy bells and whistles the better.

Then there is th fact that only a small group at each forum is taking part.

On the other hand, they must know where I am, and if they really
wanted my advice, they'd email me for it.

Meanwhile get a small flow of private emails from
peaceful folks trying to build things, and at least they are trying to do
something,
not just sitting around typing.

RAT takes up all my TV time.

Patrick Turner.

"Patrick Turner" wrote in message
...
for example not all forums work with Netscape 4.7 ...

Or maybe, just maybe, you should enter the last two new decades...

Tim

--
"California is the breakfast state: fruits, nuts and flakes."
Website: http://webpages.charter.net/dawill/tmoranwms

Patrick,

That's funny... I've never had a problem accessing any of the forums
(unless, of course, their servers went down or something). Tim might be
right about upgrading your browser. New versions can be downloaded free from
the internet.

Then there is th fact that only a small group at each forum is taking part.

The same thing happens here. I just read stuff for quite a while before
posting anything at all - I'm sure there are many others.

Have a look around diyAudio
http://www.diyaudio.com/forums/forum...p?s=&forumid=5 , if your
computer will let you. Sure, there's some noise (there's plenty of that
here, too), but there are lots of worthwhile discussions taking place as
well, which could definitely use your contibution. It certainly would be
more worthwhile than continuing that silly thing about tranformers with Phil
that not many people are paying any attention to anymore...

Jason.

On Fri, 4 Mar 2005 21:38:16 +1100, "Jason R."
wrote:

Frankly, your posts on this board are so maliciously worded that they are
not worthy of a reply, but against my better judgement:

Kill-file the asshole and move on.

"dizzy" wrote in message
...
Kill-file the asshole and move on.

I already have.

On 3 Mar 2005 16:10:14 -0800, "wildfire" wrote:

Thanks for all your feedback. The amp spec is not important. It can be
of a low-tube amp nature. What is needed is a power tube that can
handle these general specs...

1) 1000-2000 volts
2) lowest heat generation
3) switching capability at least 100 times a second (clean switching
like a transistor)

This is not being used in an amp, but for a science project.

sci.electronics.design, sci.electronics.basics. Maybe someone there
can tell you.

- YD.

--
Remove HAT if replying by mail.

On Fri, 4 Mar 2005 18:36:15 +1100, "Phil Allison"
wrote:


"Jason R." = masturbating imbecile

There are probably many valves that can satisfy your critera


** Really Jason ??

Name one readily available and moderate cost tube that can switch like a
POWER transistor. That means the "on state " voltage is less than 2 volts
while the "on state" current is several amps.


Thyratrons and ignitrons might serve, don't know too much about them.
Bitchy to turn off AFAICT. I do have a 2050 lying about in a shoebox
somewhere. Might be fun making a dimmer out of it.


The ****wit OP cannot describe what he needs at all - so NO-ONE can give
him advice.

He does seem a bit foggy on what he's asking for.

- YD.

--
Remove HAT if replying by mail.