Coil amplifier

[camerart]

I made a coil amplifier a year or so ago, for locating a signal wire position. It gives 2X outputs, and connects to a PIC A/D inputs for the calculation. See attachment:

It has caused problems from the start. It wasn't strong enough, so 2X transistors were added 'TR1 TR2' a second Diode was added, in series with D3, as a voltage lifter. The LM324 has a problem where if any pin receives -0.3V, the chip gets upset, so Schottkey Diodes were added at pins -IN, pointing towards GND.

Sometimes the whole thing works fine, then something changes, and the calculations go out.

When I used it at first before adding the Transistors, I'm sure the output range was 1to5V now it is app 0.5Vto1.2v So a weak signal on one side won't register and the other side could be reversing due to the -o.3 LM324 on pin problem.

I hope this makes sense. Thanks.

 

[bureaupro]

Metal detector coil amplifier

Hello!
I can help someone with a scheme to enhance signal reception, a metal detector search coil for total, operating with 14 kHz?
Bs Reg.

 

[camerart]

Hello!
I can help someone with a scheme to enhance signal reception, a metal detector search coil for total, operating with 14 kHz?
Bs Reg.

Hi Bereaupro,

Can you clarify please?

Cheers.

 

[bureaupro]

Hi Bereaupro,

Can you clarify please?

Cheers.

I have a Metal detector White's M6 and I want to increase the depth performances,amplifying the signal reception of coil search.I want a schematic something like this:.I mention the detector working with 14 khz.

 

[duke37]

I do not know what a coil amplifier is but your circuit seems to have some strange details.
1. There is a 1k resistor across the power supply, this just takes power to no pupose.
2. The first op-amp provides a voltage reference for the other two amps. This feeds a capacitor and a 1k to ground. You would be better moving the capcitor to the input and eliminating the 1k to ground (see 1).
3. There is no power supply smoothing, An electrolytic between Vcc and GND would do no harm.
4. The outputs have 100n capacitors referenced to Vcc, It would be better to reference these to GND especially in view of 3.

 

[camerart]

I have a Metal detector White's M6 and I want to increase the depth performances,amplifying the signal reception of coil search.I want a schematic something like this:.I mention the detector working with 14 khz.

My set up amplifies a signal from a wire, where a Metal detector sends it's own signal.

It's a bit different, see if there is a section about metal detectors.

Sorry can't help.