Re-Inventing The Wheel-Part1-Clemente_Figuera-THE INFINITE ENERGY MACHINE

[SolarLab]

Op Amp Evaluation Boards and ICs

Mouser Electronics - Engineering tools - evaluation board op amp (some populated - some bare boards
you populate with you're choice of op amp - bare board $6.65, etc.); good selection lattice and
documentation:
https://www.mouser.com/c/?q=evaluation%20board%20op%20amp

Digi-Key - Evaluation boards Op Amps (some populated and some bare boards $5.90 etc - you pick the
op amp); good selection lattice and documentation:
https://www.digikey.com/en/products/filter/evaluation-boards-op-amps/788?s=N4IgTCBcDaIPYAcAEBDAtsgRnFAnAJiALoC%2BQA

Both are reliable sources, fast delivery and, I believe, still offer Technical Support (phone or email). Check them out.

SL

[SolarLab]

I think a regular more efficient amplifier may work..  Those Class A's are hot inefficient beasts.. 

Signal generator set to Triangle- then run the Stereo amplifier output through a bridge rectifier.  It flips the negative side to positive and evens out nicely.

Or if you want to mimic figuera's steps, you can use Post or Neg Ladder through a rectifier.  Again it flips the negative side to positive in an equal manner. Now it look like the resistor rig.

Then just use 2 channels and set the phase to 180. 

(using regular sine is close, but it V's at the bottom a little too much, unless your signal generator can make a half-circle sinewave. )  But that triangle looks pretty dead-on to me..

Now I don't have to wait weeks..

FWIW - Your FG has AWG (store arbitrary signals) so you should be able to store an "Up Ladder" + "Down Ladder" sequence
(and vice-versa for your other input) and replay them in a loop.    I haven't tried it so just guessing? But might be worth a look.

However, you might have to "build the waveform" using the software supplied with the generator [another option].

SL

[SolarLab]

Analog-Digital Circuit Simulators

Before buying any Op Amps - an option is to use an Analog Circuit Simulator like LTspice.

My favourite is Spectrumsoft's Micro-Cap but it appears it has become obsolete (ceased
updates a while back and the web page is gone  ).

But there are a few others out there that are free. LTspice is still available and seems popular.

Might be worth the time to learn and use plus there seems to be lots of help available.

A good tool and skill to have IMHO... (check if your design will work before spending any $ ).
Also helps with documentation and presentations.

LTspice
https://www.analog.com/en/design-center/design-tools-and-calculators/ltspice-simulator.html

TINA-TI (demo or paid version ?)
https://www.ti.com/tool/TINA-TI

NI - Multisim (not familiar with the newer versions)
https://www.ni.com/en-us/shop/electronic-test-instrumentation/application-software-for-electronic-test-and-instrumentation-category/what-is-multisim/spice-simulation-fundamentals/spice-simulation-overview.html

Good Luck with the build!

SL

[floodrod]

FWIW - Your FG has AWG (store arbitrary signals) so you should be able to store an "Up Ladder" + "Down Ladder" sequence
(and vice-versa for your other input) and replay them in a loop.    I haven't tried it so just guessing? But might be worth a look.

However, you might have to "build the waveform" using the software supplied with the generator [another option].

SL

The image I posted is using a regular stereo amplifier.  I got the wave full positive bias after the amplifier...

Scope is hooked up to the DC side of bridge rectifiers on the output of the stereo.

[gyulasun]

My favourite is Spectrumsoft's Micro-Cap but it appears it has become obsolete (ceased
updates a while back and the web page is gone  ).

Hi SolarLab,
Wayback machine can retrive all versions of Micro-Cap from the original site.   Spectrumsoft made the software free in 2019, you may have heard it? https://www.youtube.com/watch?v=bjn-252Oo7A 

And see this link to download the different versions, up to v. 12.2.0.4 :   https://web.archive.org/web/20201107223859/http://www.spectrum-soft.com/download/download.shtm 

Gyula