Kapanadze Cousin - DALLY FREE ENERGY

[BlackBishop]

I don't post much (just one post so far ) but I read a lot many about various things and it may be useful for somebody to use that knowledge.

I don't want to discourage you from replicating Dally circuit but to give you some alternatives.

If you want to produce high voltage, high amperage, ultra short pulses without poking with DSRD you may consider using avalanche transistor pulse generator.

Few links to look at:
www.phazitron.narod.ru/geo/avalanche_1.pdf
http://www.ccsenet.org/journal/index.php/apr/article/download/3287/3601&ei=Ba6fUJv1FY7KtAb4poDwCQ&usg=AFQjCNHsguyV3Yo8UWvnAcrK708vbzUQ0g&sig2=OU1SA1ciUYWdMN7fA1EVkQ

ftp://ftp.sic.rm.cnr.it/incoming/ifa.rm.cnr.it/Maurizio.Viterbini/Public/HPSSLaser/LaserDrivers/RevSciInstrum_62_1031.pdf

This should you give sub nanosecond pulses.
If you want more info use google "avalanche transistor high power pulse"

Other thing I want to mention are nonlinear transmission lines - they are able to squeeze pulse edges which is opposite to dispersion one should expect 
There are at least two types:
- first using active elements (diodes) - it can make rising / falling edges in picosecond range but it is only for low voltage so no use here
- second completely passive (ferrite loaded transmission line) - this should apply here.

Some info here
http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-5432.pdf

For more use google "nonlinear magnetics pulse sharpening"

And for the end - DSRD circuit 
http://accelconf.web.cern.ch/accelconf/e08/papers/mopp017.pdf

[Сергей В.]

to Itsu

Try to get for the first time pulses without DSRD diode. When you made succeed try all Diffusion diodes which you have !! If you make shoping on EBAY seach for КД226 - KD226. With them you can pump-up your Nano-Pulser up to 2KV from 150Volts.

Удачи Сергей В.

[Osiakosia]

Dear friends ,
There is latest news from www realstrannik.ru .
High-voltage , high-speed swithes :
www.alphalas.com/products/laser-accessories/high-voltage-switches-and-nano-second-generators.html

Best regards for all .

[itsu]

@all,

I redid my nano-pulser (np) per verpies latest changes (pins 3, 9 and 12 grounded), added a 10K resistor in the trigger transformer secondary and changed to a IRFP260 MOSFET.

I have a solid signal on the np pin 8 and 13 and can vary the pulse width between 12 and 750nS.
MOSFET driver still the ucc27511 with 2x 4.7 Ohm resistors.

1 Ohm csr now gets hot at widest pulse.

Going to test my junkbox diodes with this setup.....

Video: http://www.youtube.com/watch?v=W7Q-80r_PIw&feature=youtu.be

Regards Itsu

[verpies]

1 Ohm csr now gets hot at widest pulse.

If the 1Ω CSR gets hot, then put 2 or 4 of them in parallel to obtain 0.5Ω or 0.25Ω CSR that will dissipate 4x or 16x less heat, respectively, as well as increase the V/R limit.  You seem to have sufficient space for more resistors in parallel.

The core of this trigger isolation transformer is soooo slow to respond to the signal changes.  I guess these magnetic domains in the core just cannot move that quickly or the interturn distributed capacitance is slowing down the signal. 

You would be better off triggering your scope on this capacitively coupled signal from pin 4/8, because its amplitude does not decrease as you decrease the pulse width and it is more stable in time.