I just found a higher resolution video of this small toy generator that drives 2 Fans in 720p resolution.

https://www.youtube.com/watch?v=WGjlaAllUIU


there you can much better see these H bar hydrogen foam rectifiers...

His first generator was pretty complicated inside, as you can see here:

https://www.youtube.com/watch?v=Syd6O9M-nrU

these 2 metallic electrodes which are puts in there could be Silver and Zink metal, which gives off a difference voltage of about 1 Volts,
which is probably enough to start these 2 oscillators sitting on the sides of the case to generate the hydrogen electrolysis...
How the question is only , how does he rectify this hydrogen foam into DC in this small unit ??

Ok, there are generators on Gunn diodes and how is it powered?
Maybe it's just a kind of chemical battery with electrodes.

Gunn diodes are not for current rectification. I never knew. There are other microwave diodes for this.

Just uploaded the Home Power Generator Video,which I paid a translation service for , here now:

https://youtu.be/d8WmrCY7pCY

Please join my YouTube membership channel tohelp cover the costs for the translations. Many thanks.
Regards, Stefan.

The energy source in this case is the galvanic cellof his Silver and Nickel electrode that gives off about 1 Volt, thatPowers the 2 side PCBs with the GHz oscillators..
These use probably very low current, so the galvanic cellis only consumed very slowly...But the main feature is the high conversion efficiency of the GhzElectrolysis to DC conversion in his H-bar rectifiers...
Hope this helps..
Regards, Stefan.

So maybe he is using the Gunn diodes only for the production of of the hydrogen und uses other transistors just to rectify theRF energy from the Hydrogen foam he has produced inside the small Toy case, where he powers the 2 Fan motors ?

Gunn diodes are meaningless here.
A working Gunn diode is similar to an ordinary resistor with a resistance of 2 to 10 ohms. Only at a certain voltage and current  it  begin to generate microwaves.
Microwave generated by the Gunn diode, broadband, has a poor spectrum. It is necessary that the diode work inside the resonator, and an additional filter is needed after the resonator. Therefore, Gunn diodes are not used in modern communication equipment. For generators on transistors, the microwave parameters are better, the efficiency is higher. Gunn diodes require a powerful power source that is capable of producing at least 1 amp 3 volts to get some 0.05 watts of microwave.
Microwave rectification generated by a chemical reaction? This might be happening, but I don't know anything about it.

Where is this Zografos Style Antenna from ? did you build it yourself ??

Yes, I made a similar antenna at about 22 GHz, because that's where one of the resonances of microwave absorption by water is located.
Antenna material is special PTFE.
Didn't have any success. No effects found. The diode inside the antenna heated up and burned out due to poor cooling.
This is variation of the so-called BowTie antenna. https://www.google.com/search?q=BowTie+antenna
This antenna can work to RX  and TX. At frequencies of 22 GHz, it can be used for communication between cell towers, where cable communication is not possible. It could be an industrial component that is inside a cell tower antenna:
https://overunity.com/16440/hho-generation-using-high-frequency-electromagnetic-waves-on-water/msg533458/#msg533458
https://overunity.com/16440/hho-generation-using-high-frequency-electromagnetic-waves-on-water/msg522408/#msg522408
What I find strange about this Zografos video with a toy model and a fan:
To the Bowtie antennas, to the metal surfaces themselves below, some metal boxes are attached (soldered?) From which foam comes out, probably from a chemical reaction. But these boxes are somehow senselessly attached, from the point of view of microwave technology. If you need to put the microwave in boxes, then you need to make their size larger than the size of the antenna. Integrate the antenna into the box.

What kind of rectifier diodes do you think he has at theseH-bar inserts  ?

It depends on the frequency. Up to 3 GHz, zero-bias Schottky diode HSMS-2852 are often used in microwave energy harvesting topics.

https://etd.ohiolink.edu/apexprod/rws_etd/send_file/send?accession=osu1348776239

At higher frequencies, microwave detector and mixing diodes can be used. But the rectified current will be very small, 1-10 milliamper 1 Volt .For sample:
https://www.ebay.com/itm/125493339049
https://www.ebay.com/itm/234909884530
https://www.ebay.com/itm/261298468683

I'd also done this things for many years ago.

Based on the size, is it for receiving television from Western satellites during the times of the "Iron Curtain" of the USSR? Or "anti-radar"?
Good job! Functioned?

This new video could help a bit more, which  I just converted only into the English subtitling...
Please switch on the ENglish subtitles..

English Audio will come tommorow..

https://www.youtube.com/watch?v=C_QIQ3azOl4