try Hertz question / problem

I did today quickly Department work practical experiments with my physics prof before the holidays to my. at least we tried it...
radar is the main theme, experiments relate to the reflection experiments of heinrich hertz, 2 parade with spark gap & dipole in the focal point who will face off, at a mirror high-voltage source is connected ne which regularly spark, induced voltage in the antenna at the 2nd level...

in our case is the hv-an Influenzmaschine, source part fat, tighten 3 times and you have one hit over 3 cm: mrgreen:

the induced voltage can be measured by one just on the 2nd appends an oscilloscope to page, also on the weakest gain switches and switches the probe to 10 x, you get values with reasonable crowds the oszi hasn't hurt the but you can't say for sure whether the second mirror has anything to do so because the oscilloscope or the cable to the oscilloscope received the signal without parade & antenna. -.

does anyone of you idea what you could do ne? the cable to the oscilloscope should prevent exactly something like this as a coaxial cable or?
in the original, which was try with a coherer 2 carried out mirror, I might try that also, but that is cumbersome and it works I not so think as it should...
could you make some simple electronics for this? the secondary voltage ca 100V-200V might...
or fält what you insulate the pipe or similar? What could you as a display on the 2nd page use? Probably arise just 100... 200V against earth. That would explain the oscilloscope displays something like this.
The solution would be to use, but a different display circuit example no oscilloscope.
The easiest way a transistor that controls an LED for example.
The transistor needs a fairly large base resistor, for example 100kOhm.
And most important: from emitter to base even a diode, anode emitter and cathode for basic needs. It prevents the emergence of a negative voltage on the base, which would otherwise destroy the transistor.
You should then run the circuit with a battery or a rechargeable battery, so that it really has no connection to the Earth. The receiver provides sure more than a few µA. That should do it then.


Of course, you can take also a FET. But please no power MOSFET, but what small, z.B a 2N7000.
Power MOSFETs have indeed pretty much gate capacity.
The FET needs still a Zener diode from gate to source, so the gate gets no surge. And a resistance from gate to source would be good as well, so that the gate does not self-excite. So 10 mohm should be ok. I built even just the attempt by Hertz. A student thesis is also with me. With me to (round) wireless technology revolves.
For me, a spark went as an indicator. The range is although not too large with a few cm and the spark length is anything but big, but I can prove the radio waves. I can prove the reflection and shield the radio waves it. When I ne metal plate in between, is the spark in the receiver. I got when first also tried secondary spark to generate but I saw nothing there...


What are you used because as HV source? I've now even assembled my fritters, in an empty ink cartridge. Now the Bell must reasonably to iterate and then ancient radio receiver is my anno 1900 finished. at what time intervals than spark ignition coil?
does the fritters for decent work? If you want to transmit Morse code, you have to shake the fritters which with a Wagnerian hammer, so that the iron filings by the radio waves, is again zerstreun.