JNL is doing a Meyer's replication

[alan]

(I shouldn't post this here, but what the heck don't know where else)

I am looking for a good USB oscilloscope, which one do you recommend?

[NerzhDishual]

Hi witty Guys,

@Alan (included in the witty Guys  ) :
I'm 60 and retired. I have and old (1977?) Hameg HM 207 oscilloscope, so I cannot be of
any help about USB ones... I was into RS232 and DOS. It works pretty well for
'discussing' with meteorological moored buoys's sensors and also with data transmitters
for geostationary satellites. http://www.meteo.shom.fr/real-time/ ...
---------------------------------------------------------
NE555 are fine and very versatile.

I have been playing with these gizmos for a long time.
The problem is: with the "555 average circuits" over there on the Internet including the
very Dave Lawton one, when you tune the Duty Cycle you detune the Freq and
reciprocally...

If you do not want to detune your Freq when tuning the Duty Cycle (and reciprocally), you
must have two 555 . One in Astable mode (for Freq) and another in Monostable mode (for
Duty C.). It works, should you well choose all the R and C values! I have done it.

Please see http://freenrg.info/Hydrogen/electricfence.pdf

Now, about this bl' JLN WFC replication:
What kind of transformer (220V/12V) is he using. A toroidal one or a
common 50/60Hz DC power supply AC/DC transformer (in inverse way, by the way)?
In that case, is this transformer suited for the claimed 11KHZ Freq)?
Else: what are the Duty cycles of the 2 square wave oscillators?

To me, this is Half-Opened Source...    

Best

[alan]

I think an older scope also would suffice, gonna look for a second hand one.

Well, everything is there:
- The 250Hz signal is 50%
- The 11 kHz signal is about 22 pulses per period of the 250 signal, count the spikes in the picture. Duty cycle is unknown,  I think the lower the better. Both frequency's  must be variable, every wfc is different.
- The site says this about the transformer:
The T1 transformer is a common 220v/12v 60VA transformer used in reverse mode. The use of a toro?dal transformer with a ferrite core will be better to minimize the HF losses in the core.
Looks like he is using a regular transformer, else he would have put a toroidal in the schematics. 

[troyd1]

@NerzhDishual - To me, this is Half-Opened Source...

I have followed the JLN website for a while. JLN always post everything in a straight forward way, encourages replication and even creates pages for others that have replicated. He always posts his email if you have questions. If it appears half open, point out where and send him an email and I am sure he will clarify. He is now working on version 2. Hope he gets done soon.

[NerzhDishual]

@Alan:

Yes, your are right. The site says about the transformer!
I just did not read it straight...

I have made a circuit with a single 4093 and 2 potentiometers for
tuning the 2 freqs (about 200-300 Hz) and (about 10-12 KHZ).
100 nano cap + 47K + 22 K pot / 22 nano cap + 47 K + 22k pot.
It works well on my test board (ugly version).
I have not yet managed to get it run fully in the nice version
(the one in a plastic case). 

I have also purchased some micro wave oven diodes.
Things are going on slowly....

@Troyd1:
OK.OK.
It is not Half-Opened source. Would I say 85% opened??? 
Just kidding.

More to come soon...
Thanks for you replies.

Best