Oscillator

[Teleno]

Not more powerful,Q factor is very high.

The current at the coil is 2,5 times higher for the same battery voltage. The magnitude the magnetic field is proportional to the coil current. This oscillator goes deeper, uses less components and the transistors don't degrade by high reverse Vbe voltages.

[scs]

Transistors works in grounded colector schematic. R input is high. Reversive voltage in transistors is high.

[Teleno]

Transistors works in grounded colector schematic. R input is high. Reversive voltage in transistors is high.

The plot V(b,e) proves otherwise. Max. reverse Vbe is -0.9V for Q1 and 1V for Q2. Compare that to -20V in your design, not reliable. When your oscillator stops working now you know what happend.

[scs]

Simulation of your circuit does not work on program proteus. It works this.

[scs]

You'll do well to take the soldering iron and see how your circuit actually works. Then write.

You'll do well to take the soldering iron and see how your circuit actually works. Then write.

[Davor]

Reverse Vbe works mostly as a Zenner diode, and they'll be fine unless the current is too high. Horizontal deflection transistors did that all the time... and often released the magick white smoke.

[ivconic]

Reverse Vbe works mostly as a Zenner diode, and they'll be fine unless the current is too high. Horizontal deflection transistors did that all the time... and often released the magick white smoke.

Good old days! '80s and '90s ...
And ultimate survivor Toshiba BU208!
Later on BU508D!

I am still carrying "watermarks" on my skin, at hands mostly, for acting too "smart" and brave to "service" those stages unprotected and with bare hands.
Once 25Kv voltage literally drilled a 8-10mm hole through my hand and knee... down to chair and floor. I could peek through knee and see how bones are moving.
Some people shows up with their tattoos; i am showing up with my high voltage scars and watermarks!
It's the Tesla inheritance...

Ok...
Guys ... guys... guys.... what's so good about "my is bigger than yours" pi$ing contest?
So much debating about totally irrelevant thing.
Today there are still many ways to skin a cat .... and zillion times more to make an oscillator.
Especially in digital domain.
Big deal.
Show me how to make money, not oscillator. F.uck oscillators! Of all kinds!

[scs]

To Davor
Thank you for this explanation. I was tired of writing to me for reverse voltage

[ivconic]

[scs]

Lepa Brenna is better than that. I did a 4.5 kHz detector with this oscillator. Works extremely deep in land. The oscillator is something of great.

[ivconic]

Lepa Brenna is better than that. I did a 4.5 kHz detector with this oscillator. Works extremely deep in land. The oscillator is something of great.

Each hobbyists is having sort of a "holly grail" in mind. Something to striving to achieve.
I can not tell for others, i can only tell what's my "holly grail".
It would be the simplest as possible detector, able to detect small and tiny silver or/and gold ancient (Roman, Byzantine) hammered coin, situated not deeper than 25-35cm in soil.
Now, this will need additional clarifications.
The soil! THE SOIL!
The soil is such type that's usually met at such sites.
Very hard and tough soil, mixture of dirt, ancient ceramic particles (from bricks and pottery), burned and melted chunks of iron and iron oxide and at the end with addition of lot of hot rocks pieces scattered around.
All that on not so leveled terrain, a hill actually, a rocky hill with lot of small and dense bushes.
Once it was fortitude, fortress. At some point in history it was attacked by enemy and trashed to the ground. Lot of fire, lot of stress and lot of melting and mixing of various organic and non organic materials.
So... such silver and gold coins are still there. Untouched. Buried under a piles of such material, under such "soil".
I've been trying with probably 100 different models and brands so far. NONE did the complete, nice and easy job there.
Deus was closest. Yet too far away. Minelab GP was probably the most capable; yet impossible to carry it and operate it under such horrible conditions. Additionally its large coils are not able to reach most of the spots there, because of the curvature of soil and bedlam of various obstacles.
SMW did great job up to some point. Problem with SMW is because it picks up too much iron too. So you become very exhausted from digging with it.
So... obviously i am still searching for my own personal "holly grail". Still haven't founded it.
It has to be the way i explained, to be able to beat such conditions and it has to be with smallest possible coil ... and yet to be able to reach such depths.
So far... still searching for it and hoping.
Maybe this one is my holly grail, can't tell; but haven't heard from Nupi for long time, i really do hope that he is alright.
Please take time and watch all the videos with patience. This is the real deal.

https://www.youtube.com/channel/UCjL...xyxEeTsuI8cVhg

[ivconic]

Very close to what i call a "holly grail" for such conditions was a Deus with HF 22.5 coil, tuned to 14kHz or so... can't recall.
I had that coil on testing only once. Only for few hours. So i am not sure.
There was no enough time me to know it better.
Ever since than i am planing to obtain it. But ... it is not that easy for me.
And there is another aspect that i must mention here; HF coils will work only with f/w updates 4 and above.
And what they did in XP at update 4 and above? They messed up the GEB function BIG TIME!
Although they claim that there are so many significant improvements at those updates, especially at GEB, added new GEB features... somehow i can not accept those changes.
I tried and i involved huge efforts to try to understand what the heck they added and "improved" there. And i failed each time.
GEB with all its additions and extra functions they added in versions 4 and above... are complete "$hit" as far as i am concerned.
Everyhting else they did very nicely in those versions; is simply totally spoiled by such bad move on GEB function, which is VITAL!.
That's why i am still at V3.2 with my Deus. Most reliable among all. Recently i tried V5. Than i vomited BIG TIME and than i did another downgrade to V3.2.
So... will buying HF coil make any sense... considering all?
I would really like to have few minutes of conversation with the one who decide in XP... there would be lot of spitting and name calling... maybe arm twisting too.
And that's why i don't glorify XP any more. That's why i am seriously considering to switch a brand and model.
Or to see what's with Nupi and how to obtain his work.

[scs]

For good real depth in salt soil, the coils should have a bad Q factor. A capacitor over 100 nf .

[ivconic]

For good real depth in salt soil, the coils should have a bad Q factor. A capacitor over 100 nf .

I am glad to read that. It just justifies some of my standing points.
Also it totally destroys some of the pseudo theories made by one of your compatriots.
I had lot of disputes in the past here with him along with administrators taking his side.
But let's keep that as water under the bridge.
Point is; you are right.

[Teleno]

I am glad to read that. It just justifies some of my standing points.
Also it totally destroys some of the pseudo theories made by one of your compatriots.
I had lot of disputes in the past here with him along with administrators taking his side.
But let's keep that as water under the bridge.
Point is; you are right.

That would depend on the method of detection, would't it? If it's based on variations of amplitude then high Q offers more sensitivity and therefore more depth.

Regarding reverse Vbe why woul anyone go for it when you can do the same without and with a simpler circuit goes beyond me.