Tubes?

[BEP]

Anybody ever compare the slew rates between VT and SS OPAmps? Pretty strange... (at least for common SS opamps)

[Jdo300]

Hmmm.... Yeah looking at the specs fro the Tube Op-Amp was less than impressive. About the only good thing is the fact that it can swing +-50V unlike the SS counterparts. The slew rate was definitely less than impressive at 15V/uS. Most of the driver circuits I have built for my MOSFETs can switch 15V in under 30 ns, for an effective slew rate of 1500V/uS.

Now if tubes are supposed to be so fast like SM is obviously implying, then what am I missing here? Or is his definition of fast and my definition of fast totally different??

God Bless,
Jason O

[Earl]

"to tube or not tu be, that is the question"
Shakespeare

Hi All,

I have several things to say about this subject.

1- A scientist can not prove everything and has to accept "truth" that has been found by others before him/her.  That said it could still turn out that, for example, the Sun does not function based on hot fusion.

2- A TV repairman may discover something extraordinary and in spite of investigating this during many years, may never understand how and why it works.  It can not be excluded that some of his ideas and opinions are incorrect.

3- Being a TV repairman does not mean that you understand radio frequency interference control in SS circuits.  Years later after SM finally learned how to control and combat RFI and REI, he used SS circuits with no problems.  Thereafter he forgot about tubes and did not look back.

Personally, I think

A- the function of the TPU has absolutely nothing to do with the Earth's magnetic field.

B- SM's first experiments used tubes and sine waves, while later and better versions used solid-state electronics and square-waves / pulses with transition times as fast as possible.

C- while SM says that tubes have fast transit times, I have reservations that any tube can be as fast as modern solid-state electronics.  I would like to stress that the fact that tubes are physically much larger than solid-state circuitry means that they must be slower than SS.  Being smaller does not guarantee faster operation, but being larger means that the circuit *** MUST *** operate slower.  Do not think that for one second that a tube can operate at the speeds that modern SS circuitry does.  Even small tubes, such as nuvistors, are not as fast as today's SS devices.  FETs, transistors, and laser diodes can operate at many Gigapulses per second as proven in modern fiber optic systems.

Please look at the attached PDF file to see a simple SS circuit, with which even audio transistors can achieve switching speeds in the picoseconds region.  Notice however that the circuit *** MUST *** be small to achieve fast transition speed.  Every nH or fraction of a nH in the discharge loop will hurt.  It is possible that electron avalanche in a semiconductor junction is much faster than any transit frequency of a vacuum tube.  I suggest that serious researchers take a serious look at electron avalanche in P-N junctions. Using diodes or transistors that breakdown at hundreds of Volts or even 1 or 2 kV at picoseconds speeds could be very interesting.

I believe that using HV picoseconds [or low ns] pulses is the correct road to OU results.

Earl

[BEP]

@Earl,

All good points

@All

What would be a common OP Amp in the 90's? A 741 perhaps or similar. Slew rate for a typical 741 is .5V/microsecond. That blows even compared to the VT OP Amp designed 40 years before. SO SM's comments were probably correct - for that time.

I have no doubt any VT circuit can be done with SS - and many more. There is one question I haven't found an answer... How do you use a SS switch to apply a potential to an open circuit? Easy enough to do if you use a passive device to do the dirty work - xfmr/cap coupling, etc. But how can you do it directly with no passive devices used as couplers?

That is the only thing where I can't find a SS fix. And of course the fact that VT can and does a lot more than switch or act as a valve. Especially if you screw the circuit design  - unwanted radiations of all kinds!

>>Edit

I struck out the question above as I have just skimmed over the PDF provided by Earl. This doesn't answer the question it just may provide the same effect. I need to read it completely.

[MACEDONIA CD]

HI   
SOME  MAY THING S  ABOUT THAT TUBE     IF  TPU HAS  TUBE    I THING THE TUBES ONLY NEED TO  DISCHARGE   SMALL CAPACITY CAP WHIT HV  DC  FAST  ?
HM  LETS SAY  SIMMPLE  THINGS  IF WE NEED TO CREATED   STRONG ELKTRO MAGNET COIL   HOW WE BE MADE STRONG ELKTROMAGNET COIL  WHIT CAP AND SOME  TUBE 
..
OK  SMALL ELKTRONICS  PUMP THE SMALL CAP  WHIT  HV DC  AND LET SAY FOR THIS JOB FOR CHARGYN CAP   HE PUT 1 WATT IN ONE SECOND TIME   AND THEN   HV CAP IS FULL WHIT HV DC  AND THEN  TUBE   MAKA SPARK AND DISCHARGE  THE CAP IN TO THE SMALL COIL    .. WHEN CAP IS DISCHARGE   HI PRODUCED  ONLY  <<<COURRENT IN THE COIL   ,,<<NO VOLTAGE    ONLY COURRENT  MUCH MORE THEN   CAP WHIIL CHARGE    ...HMMM    SIMPLE  ONE  WATT ONE SECOND  IN ENERGY    10 WATT PRODUCED WHEN IS DISCHARG  IN THE COIL  WHIT HELP  LET SAY TIBE   ,,,TUBE  OF NEON BULB STARTER >>

HOW WE BE CREATED  STRONG ELKTROMAGNET WHIT ONLY  CUORRENT NO VOLTAGE WHEN IS DISCHARGE THE CAP 
FRIEND  ALL TIME A SAY   <<THERE YOU FIND  SIMPLE FORMULA     BUT IS VERY GOOD FORMULA   ... HOW WE BE MADE COIL VACUM  ONLY  WHIT AMPS  WHEN IS DISCHARGE THE CAP   ..I TELL YOU  WE DONT NEED  VOLTGE TO CREATED STRONG MAGNET FILD   WE ONLY NEED AMPS  WHITOUT VOLTAGE    .... ANSFER IS   DIS EFECTKT IS ONLY BE PRODUCED OF  <<DISCHARGE  THE CAP  /..
CAP GIVE AS ONLY AMPS    NO VOLTAGE      ... A COILS IS NEED AMPS TO CREATED THE STRONG ELKTROMAGNET FILD  HERE WAY IS NEED AMPS  NO VOLTAGE FOR ELK.MAG, FILD   HERE IS SIMPLE FORMULA  LOOK AND ALL WE BE EASY TO ANDERSTEND


                                    H = AMPERS /  METER 

    H  ---- IS ELEKTROMAGNET  FORCE IN THE COIL

AND  IF WE BE MADE SUCH AS LIKE THIS COIL  WHIT PUT THIS AMPS THERE WE BE CREATED STRONG ELTRO MAGNET THERE   HO WE BE PRODUCED MOVIN MAGNET FORCE TO EXIT COIL   

LIKE SIMPLE TRANSFORMER     IF TRANSFORMER  HAS  MORE ELKTROMAGENET FORCE IN THE CORE  THEN THIS TR,, HAS MORE ABLE TO PRODUCED THIS FORCE IN TO THE  ELKTRIC POWER

I SAY MAYBE  S.M  BIG TPU IS LIKE  TESLA  COIL  I SEE THERE  TWO BIG nf  cap whit hv  and this going to big ring of top of thr tpu  ..cap is discharge directly in  the top of the armature coil of top of the ring