3v OU Flashlight

[Sergh]

Hoppy, this is normal. For low-frequency measurements will be only one connection to ground.

[semenihin-77]

Сейчас я исследую другие сердечники, мне кажется что феррит не идеален для такого устройства.
К сожалению мой генератор не совсем исправен, поэтому я немного мучаюсь при настройке.

Now I'm looking into other cores, I think that the ferrite is not ideal for such a device.
Unfortunately my generator is not quite working properly, so I am suffering a bit when adjusting.
http://youtu.be/zjzvmhRfa08

[Sergh]

  3v OU Flashlight - remains unclear, why the resonant frequency is 269 - 270 hertz?

[TinselKoala]

Wow! I am suffering as you adjust, too!

A whining signal generator and an oscilloscope! And mostly flat lines on the scope! Nice old-new Russian tech, a round CRT in a square bezel, LOL.

Just for that, now you have to watch this.

http://www.youtube.com/watch?v=NZFSnLgXfQE

[TinselKoala]

It is the ground of the probe. You see him disconnect it later on in the video. The ground on the other probe is not connected!

He also has a lead plugged into the external trigger on the scope.

Ah hah. Perhaps this means he is injecting a signal from a FG and triggering off that. I suspected this earlier.

But the scopeshot appears to indicate that the trigger channel is Ch2 (Look just below the blue pen pointer in the last scope image up above.)