Deep-searching R-TR metal detector schematic.

[Sasho- Varna, Bulgaria]

[nelson]

TR locator

Hi Sasho.
Can you tell us more about this detector?
Did you build it?
Is there a PCB?
How deep can go?
Etc,etc,etc.
Regards
Nelson

[Geo]

I am afraid that there is problem with oscillator

[Sasho- Varna]

The circuit works perfectly. Depth target is 15x15cm -1m. The oscillator amplitude is 30v pc- pc. I built it 10 years ago.

[Geo]

I can't understand how the oscillator is working . I never saw an output coil to be connecting at the input of the oscillator-amplifier (between the bases of transistors) ???? If it oscillates...the base current is very low so the output is very low.

[Sasho- Varna]

Geo, this is a push-pull oscillator. First make the oscillator only and look its oscilloscope diagram. Then write here what have you saw.

Regards.

[detectoman]

sasho: other? modern modified editions or simplifications on these detector, details on coils
have you compact version
best regards

detectorman

[aft_72005]

Hi Sasho

What is the operating frequency ?

[sascho-bulgaria]

11khz

[aft_72005]

Hi Sasho and all
Simulate only TX section with proteus 6.9 software,
In mathematical area on computer good working without
Any problem .out put frequency approximately 10khz .
Output voltage level = 60 vpp. supply voltage = 8volts.
Search coil inductance = 1500uh .
I study all of your circuits which uploaded this forum , my opinion
Are well and interesting.
Best regards .

[Sasho- Varna]

Thank you.

[Sasho- Varna]

If indicator system is smaller then 0.250 mA

[nelson]

TR locator

Hi Sasho, do you have more information about this project, like PCB, components placement board, etc.
Have you build the unit and can you tell us how deep can go?
In advance many thanks
Regards
Nelson

Geo, this is a push-pull oscillator. First make the oscillator only and look its oscilloscope diagram. Then write here what have you saw.

Regards.

[Sasho- Varna, Bulgaria]

No.I built 10yars ago. Tune c5 to maximal oscilator amplitude.

[sonar]

whops!

that Sasho schematic die on server

someone can paste it here again?

thanx!