PopularFX
Home Help Search Login Register
Welcome,Guest. Please login or register.
2019-04-22, 07:48:49
News: Forum TIP:
The SHOUT BOX deletes messages after 3 hours. It is NOT meant to have lengthy conversations in. Use the Chat feature instead.

Pages: 1 2 3 4 5 6 7 8 9 [10]
Author Topic: Itsu's workbench / placeholder.  (Read 4111 times)

Group: Moderator
Hero Member
*****

Posts: 1656

I build the nanopulser according to the PDF attached below (see diagram taken from pdf).

The pulse across a 50 ohm resistor can be seen in the screenshot.
Voltage on the drain was 200V.

I used my Russian KD226 Diode as the P600M diode in the diagram only produced a 820v pulse.

I still try various other things to improve on the nanopulse, but i have a hard time believing i could
come close to the claimed 2kV @ 2ns pulse mentioned in the pdf.


Itsu
   

Group: Moderator
Hero Member
*****

Posts: 1656

Hmmm, it seems that the capacitor(s) in series with dsr diode D (P600M) are critical.

This C (2n2/10kV and 4n7/10kV) of 6.9nF needs to be around 6.9nF in combination with P600M to produce the highest pulse.

My used 3x paralleled 2n2/3kV ceramic caps (so 6.6nF) seems to be very instable due to heat.
After soldering them in, the P600M produced, like mentioned, only a 820V pulse.
Lateron it suddenly was at 1.5kV then dropping down again to 900V or so.

Heating up those 3 capacitors with my sodering iron close by, changed the capacitance from around 7nF to more then half.

Even touching them with my finger shows a significant drop to way below the needed 6.6nF.
As they also heat up under normal operation it is hard to stabilize them at the needed 6.6nF.

I added a 4th 2.2nF cap parallel and was able by heating up those 4 caps to attain the highest pulse (1.5kV).
I need either some better quality caps or create a temperature controlled setup for those caps.


Another problem is that there is HV noise at both the gate and drain right after they switch which pops up at about 150V and higher on the drain.

This 80V HV gate noise (allthough i have a 18V tvs there) and similar 800V drain noise (allthough i have a 440V tvs) occure with or without the nanopulse present (so even if i disconnect the dsr diode).

Guess its the general MOSFET setup which causes this noise / feedback, so better chokes and decoupling is in order.


Found this pdf using the humble 1N4007 diode as pin diode to switch HV RF loads, to be used lateron:

Itsu
   
Group: Elite
Hero Member
******

Posts: 3466
It's turtles all the way down
Good work and experiments, Itsu. Thank you for demonstrating this sharp pulser.

What do you intend to do with these very sharp pulses? Do you have an end goal in mind?

Regards


---------------------------
"Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy
   

Group: Moderator
Hero Member
*****

Posts: 1656

Hi ion,

the idea is as mentioned in post #124 of this thread:

https://www.overunityresearch.com/index.php?topic=3691.msg71665#msg71665

it says:


Quote
Meanwhile back at the ranch.........


Concerning the hunt for the 45.5Mhz NMR response to an iron powdered toroid:

I dusted off my nanopulser and i will try to make it alive again, stable and boxed in.

The idea is to use this nanopulse (± 1KV) as the big gun to be fired to the iron powdered toroid to
see if this will cause any 45.5Mhz NMR response.

One of the problems will be to protect the Spectrum Analyzer / Scope inputs during the pulse, but have it
fully opened for "listening" for the response.


The above attached pdf would be a cheap circuit to try to switch the SA input off and on on the right moment.

Itsu
   
Pages: 1 2 3 4 5 6 7 8 9 [10]
« previous next »


 

Home Help Search Login Register
Theme © PopularFX | Based on PFX Ideas! | Scripts from iScript4u 2019-04-22, 07:48:49