Testing the TK Tar Baby

[TinselKoala]

TK,

The 670K is probably not needed.  You are basically varying Ibias by varying the resistor between the supply and Q2's source, which is the 100R variable in series with the 10R.  The 670K is not hurting anything either, however, just a bit more bleed when using the cap by itself.

You did use a "rechargeable" cap didn't you?

PW

The 670K is there for color-coordination, and to provide a gathering place for zipons, should they arrive early. And as anyone can see, it is a _precision_ resistor, not some cheap inaccurate garage-sale antique.

Sure I used my special rechargeable capacitor.... they are very rare you know....  but capacitors don't work with OU devices, unless they are Tesla frequency devices. There is something special about battery chemistry... you know, the battery that is completely disconnected from the circuit ... that is necessary for the unclaimed overunity effect to appear. Even though the waveforms and everything else look just the same when a capacitor is used, whether for bias or main power, the cap will always run down quickly and no free energy will be related.

[Magluvin]

It's a little scary when I see that a video I've posted gets some few views even before I've posted a link to it. Gratifying but a little scary anyway. I could never handle fame, not even fifteen seconds much less fifteen minutes of it.

Here's the link to the bias capacitor trial video.

http://www.youtube.com/watch?v=TVdzTn4Iya0

I had to watch it twice, due to the vulcan mind meld that flashing color globe to the right kept me looking away.  Mib mind erase device.  lol  it is very distracting. What is it?

Are you running the whole circuit from the cap, or just the signal gen?

Mags

[MileHigh]

Hi TK:

Good "Clip of DOOM," so to speak.  Of course that clip is another form of proof that current passes through the function generator but RA is not on the same page.  It's going to take someone that she is "friends" with to convince her of that because if you are a belligerent there is a nearly automatic disagreement with whatever you state.  (Might open up an opportunity for a  strategically placed piece of reverse psychology, you never know.)

It funny because I invented an elaborate scheme using a very large capacitor to measure the current flow through the main loop yet the solution was always staring "me" in the face - try a multimeter stoopid.  Of course one of many ironies with the massive and exhaustive NERD testing over months and months - a dynamic team in action - is that apparently nobody ever thought of putting a $20 multimeter in series with the main loop to see if there was a measurable current flow.  They played with a $10,000 digital storage oscilloscope for months and never thought to measure the current with digital mutimeter that can practically be found at the bottom of a Cracker Jack box.

For your negative offset circuit, I suggest that you keep it simple and use the power supply in series with a 50-ohm resistor to emulate the function generator.  I take it that your power supply for that purpose has no grounding issues with the scope.  If I followed everything correctly all that you need to do is disconnect the mains ground connection for the power supply.  The only mains ground connection would be through the scope mains ground.  That way your power supply negative output can connected to the MOSFET side of the CVR and bounce up and down relative to the scope ground and everybody's happy.  (I have a question to post about grounding for a separate post.)

There is a problem with your potentiometer solution to dial up a negative potential for the offset.  Let's suppose that you use a 1K linear potentiometer for the voltage wiper, and you connect a 50-ohm resistor on the wiper output and that connects to the Q2 array source.  This is just a simple hypothetical example.  If the potentiometer is set to one extreme and is set to ground, then you have a 50-ohm output impedance to ground.  At the other extreme you have a 50-ohm output impedance to -12 volts.   However, if you set the potentiometer half-way, then you have a (500 + 50) ohm output impedance to -6 volts.  The ouput impedance is dependent on the effective parallel resistance of the two halves of the wiper plus the 50-ohm series resistor.  It really doesn't make sense if one assumes that you want to work with the same 50-ohm output impedance all the time.  Don't forget that the whole mechanism for the negative feedback in the Q2 array oscillator is based on a 50-ohm output impedance from the voltage source.  If you change that impedance as you change the voltage you dial, arguably you are throwing a monkey wrench at the negative feedback part of the circuit.  I suppose it all depends on what your objectives are.

Personally I would keep it simple, and stick with 50 ohms and dial up the voltage on your power supply.

MileHigh

[Rosemary Ainslie]

MilesOffThePointAsEVer

Another ASSUMPTION where you demonstrate your vast ignorance with respect to the field of electronics.  You use that term "ASSUMPTION" as a hot-button word when you try to counter a point that someone is making to you.  However, we know your secret Rosemary.  Your secret is that you are clueless with respect to electronics and therefore you make ASSUMPTIONS all of the time.  You have to make ASSUMPTIONS because you barely know what you are doing.  You need them as part of your coping strategy.  I can't recall a single time when you sincerely asked for advice on how to do something - so ASSUMPTIONS it is.

And sometimes it's comical to see the kooky perplexing situations you get into because of your ignorance translating into an over reliance on ASSUMPTIONS.

The LeCroy will work JUST FINE without a ground plug.  Your ASSUMPTION is wrong.  The ground plug is to prevent risk to you, not risk to the equipment.
Dear lord, there are no words.

MileHigh

That ignorance for which you have no words is a fair description of your own.

picowatt - TK - Magsy - all of you who have posted here regarding this issue - In South Africa and due to the haphazard standards applied by ESKOM - we ONLY have a 220 volt power supply sources at our homes and all our plugs and are subjected to random power surges that are known to fry delicate machinery.  Not even earthing can prevent that damage.  It can only LIMIT that damage.

And picowatt I am intrigued with your 'chassis to ground' which SPECIFICALLY means that you DO tie your machine to ground.  If we in SA relied on that we'd have FRIED our machines long before it found that PATH TO GROUND. 

All this pretension.  And everyone anxious to show off their superiority.  It's the art of spin - applied with the energy of vigilantes - to stroke your own ridiculous egos.  Such bombast. Thankfully it has NOTHING to do with science.  And EVERYTHING to do with 'tarring and feathering'.

Rosie Pose

[MileHigh]

TK:

More stuff about the potentiometer issues.  If the the potentiometer is 1/2 watt, that's for the entire resistive sheet material that sits on top of the PCB substrate material.  So if the potentiometer is 95% towards one of the extremities, then that little remaining 5% of the resistive sheet material can perhaps only sustain 1/30th of a watt.  That's why lots of pots burn out when the wipers are close to one of the extremities.  I realize that you may know all of this stuff, I am more in broadcasting mode.

If you want to use a potentiometer as an exercise there is a way to do it.  Let's assume that you are working with ground and -12 volts.  There is probably a decent op-amp that you could power with ground and -12 volts that would have an output that could swing between -0.5 volts and -11.5 volts.  In "my time" the new kid on the block was the LM341.  The older standby was the 741.  You just need to wire up the op-amp as a unity gain voltage follower.  So you connect your wiper output to the "+" input and the output of the op-amp is wired back to the "-" input.  You might put a small cap between the "+" input and ground.

Now all of a sudden your wiper output has a zero-output-impedance "Hercules" output because of the op-amp.  You connect the output of the op-amp to the Q2 array source and all of a sudden you are really in business.  You can run that off a single battery if you want to and it should emulate the function generator perfectly.

Even if this discussion is purely academic, it's fun to talk about op-amps.  They are so much fun but out of the "knowledge realm" for the forums from what I can see.

Anyway, at least you don't need a variable power supply if you go the op-amp route, and you get your potentiometer for dialing up the output voltage like you wanted, and you get a proper rock-solid 50-ohm output impedance.  As long as you don't push the op-amp past it's IV limits, you have zero output impedance from the op-amp.

MileHigh