Twin T circuit wanted

What was with, "Picky, picky. To my mind, the base current robbed by the collector starves the base, lowering the CE stage's gain, until the exact equilibrium is achieved"? Where in the world did that come from... Larkin's _incorrect_ description?

I'm prepping for a trip to SFO.

On Monday I'll award a bottle of fine wine to the first person to properly show how the oscillator actually works... IF there is anyone who can :-( ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
      The only thing bipartisan in this country is hypocrisy
Reply to
Jim Thompson
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The microwave people still do a lot of math. And they use E/M simulators, not Spice.

As I noted, the basic development of microwave and radar technology was done before computers existed. WWII radars came within 2:1 of the theoretically possible target:distance detection limits. All with pencils and slide rules.

That

Spice is useless in simulating waveguides. Useful E/M simulators are a pretty recent invention.

Computer modeling has

Done before Spice. Look it up.

Just because you can't do math doesn't mean that others are similarly handicapped.

John

Reply to
John Larkin

Why would that be amplitude stable?

John

Reply to
John Larkin

Why would that be amplitude stable?

John

Reply to
John Larkin

It is usually faster, but these days, not usually better. And the speed gain is only about the operator of the sim package, not the sim. A good sim app user can beat you, hands down, and have reliable numbers to compare with real builds as well.

Sim apps have gotten orders of magnitude tighter in their iterative analysis and inclusion of parasitics, etc.

Far better than you, with or without your bench.

Reply to
BlindBaby
[snip]
[snip]

Really ?:-)

This post is only to record Larkin's asinine statement, "...reducing transistor base current hence gain..." for posterity ;-) ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
      The only thing bipartisan in this country is hypocrisy
Reply to
Jim Thompson

Oh, yes, I forgot to emphasize that engineering term, "...almost exactly..." :-) ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
      The only thing bipartisan in this country is hypocrisy
Reply to
Jim Thompson

cc

peak

nd the

-b

urrent

mes

Reducing i(b) makes i(e) fall, r(e) rises, stage gain falls. Seems okay--have I missed something?

James Arthur

Reply to
dagmargoodboat

Simulation is like breadboarding. Neither is designing.

John

Reply to
John Larkin

In my oscillator, a c-b schottky diode would keep the transistor c-b junction from conducting, and keep the transistor out of saturation. Tempco would still be low. That simplifies things considerably. Not bad.

I seem to recall the DC base voltage being about +.6. So the collector swings to just about zero, and the AC output is 2*Vcc p-p. Somebody could Spice this, if they were interested, and see exactly what happens. The transformer ratio gets involved some, too.

John

Reply to
John Larkin

Avis Rent-A-Time-Machine.

John

Reply to
John Larkin

You're an idiot. Sitting next to my breadboard is my clipboard and calculator, Johnny.

You really do have a problem using tools correctly.

Reply to
BlindBaby

--
I don't know why you're being so argumentative when it's as clear as
the nose on your face that if SPICE didn't exist you'd have very
little on your plate to offer for sale.

A couple of posts back I wrote:

"This may come as a surprise to you, but many (if not most) of the
circuits which you buy and incorporate into your products were
designed using SPICE, so the fact that you assemble them into working
product that you don't simulate doesn't mean it's free of SPICE." 

SPICE is an acronym for "Simulation Program with Integrated Circuit
Emphasis", and I'm pretty sure you use chips designed using SPICE so
even if you don't simulate circuits at the board level, SPICE is still
in there.

Also, SPICE is being used successfully in general circuit simulation
all around the world, so your naysaying is largely falling on ears
that know better.

Personally, I've been doing circuit design for almost 50 years and I
used to avoid simulators like the plague.

I've been using LTSpice for 3 or 4 years now and although I can get
along without it, there's no reason on earth I'd want to since typing
is a whole lot easier than wire-wrapping.
Reply to
John Fields

simulation is simulation, Johnny, and that is what you were dissin', boy.

And as I noted, the advanced development was done on computers.

Microwaves are strange things, Johnny. Not too hard to manipulate and observe.

That would depend on how many parameters one incorporates into any 'model' utilized.

Mid '90s

Yes, idiot. conception is a bitch. 'Done' before Spice, but optimized and modeled in the current world WITH it. ALL of the current implementations are computer designs. Sorry, chump.

Just because you ASSume worse then a street cop in a ghetto doesn't make your pig assumptions correct.

Reply to
BlindBaby

Yes, but they would not be as retarded as you claim to be scientists are by rejecting the pinnacle of human science based on Luddite mentalities

You lose... again. Completely predictable.

Reply to
BlindBaby

--
Please...
Reply to
John Fields

You use the oven to trigger the controlled oscillator.

Reply to
BlindBaby

--
Then what's your problem?
Reply to
John Fields

That one might slip past a few of the folks here, including its target.

Reply to
BlindBaby

Neither simulation nor breadboarding is a safe substitute for understanding what's going on.

Wow, you are obsessed with that part of the body, and its various products.

John

Reply to
John Larkin

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