You don't need a high speed scope if the circuit is working *correctly*. But if it's working correctly, you don't need to measure it at all. ;-) The reason for a high speed scope is to observe the behavior when it's not working correctly. It's a high-power, high-speed AC circuit, so errors or bad construction practices may produces really weird results that simply won't be observable with a low-bandwidth instrument.
I wouldn't read too much into the divisions on the scope. The probe and scope electronics will act as a low-pass filter, so you'll a smoothed and rounded representation of reality. It's not the frequency of the pulses that's the issue here, it's the harmonics that compose the rising and falling edges of the pulse. For AC pulses you can look at Arnaud's message. Godes didn't use this approach, I think - instead the clever use of T8 as both an inductor and as the primary of an isolation transformer; then by suitably referencing the secondary side, the core sees AC. I could be misreading the design, however. There are four MOSFETs in Godes design. Jeff On Thu, Nov 22, 2012 at 1:59 PM, Jack Cole <[email protected]> wrote: > Jeff, > > I don't think your scope would need that level of resolution. Godes > describes using the following: A 100MHz Fluke 196C oscilloscope meter. > > Anyway, there is not a lot of info on the net about using PWM to make > bipolar pulses. Producing a DC pulse to those specs is not so difficult. > A bipolar pulse seems to be a different story. > > I have a 25mhz oscilloscope, so I'll try to see if it has the resolution > needed. Supposedly, it will show down to 5 ns/div on the horizontal axis. > I'll try to experiment to see if I can get a 100 ns DC pulse with PWM and > see how the scope does. > > Here is the scope I have. > http://www.amazon.com/dp/B007T6XNCA/ref=pe_175190_21431760_M3T1_SC_dp_1 > > Jack > > > On Thu, Nov 22, 2012 at 3:38 PM, Jeff Berkowitz <[email protected]> wrote: > >> Interesting. A U.S. nickel is 1.95mm thick. >> >> >> On Thu, Nov 22, 2012 at 1:21 PM, James Bowery <[email protected]> wrote: >> >>> It's hard to know where to begin here but let me just say this that >>> given the speed of sound in >>> nickel<http://www.olympus-ims.com/en/ndt-tutorials/thickness-gage/appendices-velocities/> >>> : >>> >>> 5630m/s >>> >>> and 430kHz: >>> >>> 5630m/s;430kHz?mm >>> >>> ([5630 * meter] / second) * (430 * [kilo*hertz])^-1 ? milli*meter >>> = 2.0838194 mm >>> >>> In other words, a 2mm electrode should exhibit resonance at ~430kHz. >>> >>> >>> On Thu, Nov 22, 2012 at 2:47 PM, Jones Beene <[email protected]>wrote: >>> >>>> On the contrary James, at least two of us did look closely at this >>>> possibility [electrode acoustics]. **** >>>> >>>> ** ** >>>> >>>> My associate went to trouble to find and download a mpeg sound file of >>>> a bicycle bell of the same general size as Davey’s, and plugged it into a >>>> program for this kind of analysis – in fact it is dedicated bell analysis >>>> software that has proved very accurate for electrodes in the past. The >>>> natural acoustic of this hemisphere are nowhere close.**** >>>> >>>> ** ** >>>> >>>> The main freq is 4,445.5 Hz, with some sub harmonics, the lowest being >>>> around 521/545 Hz, but those are so faint as to be discarded. Higher >>>> harmonics are barely above noise.**** >>>> >>>> ** ** >>>> >>>> Thus, since the acoustics of the electrodes were off by two orders of >>>> magnitude over the signature sound, we did not think that electrode >>>> acoustics were in any way relevant as an alternative explanation, or >>>> otherwise worth pursuing.**** >>>> >>>> ** ** >>>> >>>> Jones**** >>>> >>>> ** ** >>>> >>>> ** ** >>>> >>>> *From:* James Bowery **** >>>> >>>> ** ** >>>> >>>> As I previously >>>> advised<http://www.mail-archive.com/[email protected]/msg73144.html> >>>> :**** >>>> >>>> ** ** >>>> >>>> "Look at the acoustics of the electrodes."**** >>>> >>>> ** ** >>>> >>>> Since this advice seemed to make no impact on the discourse here at >>>> vortex-l, let me expand:**** >>>> >>>> ** ** >>>> >>>> Acoustic resonance in the metallic electrodes does have a reasonable >>>> chance of bearing directly on the creation of the "nuclear active >>>> environment" hypothesized to exist. I don't think I need to expland on >>>> list the possibilities here.**** >>>> >>>> ** ** >>>> >>>> Moreover, if one looks at the speed of sound in metals, the "430kHz >>>> LENR signature" regime corresponds to the thickness of the cathodes >>>> frequently reported as exhibiting the phenomena.**** >>>> >>>> ** ** >>>> >>>> Need I say more?** >>>> >>>> ** ** >>>> >>> >>> >> >
