TL12000

[hesam_k69]

hi to all again .. thist is test of device .. device is very powerfull that i havent seen before it can detect a 24mm coin in depth of 47 -50 centimeter .. changes to device that i done is replace the 7809 reglator with 7815 replace 1 turn volume that connects to 4013 with 10 turn 100 kilo adding a 1 turn 100k pot to ne555 for frequence change .. i love this device very much ... please someone make good pcb from my schematic schematic 100 % working dont worry ..

[hesam_k69]

https://uupload.ir/view/test_tl12000_uaz2.mp4/

[Op04]

https://uupload.ir/view/test_tl12000_uaz2.mp4/

Hi,
Many Thanks hesam_k69 for the upload and all the files. Your result are so good! Do you have best coil parameter for this? Diameter, inductance, resistance, coil turn and cable diameter (cable type for coil) please give us more details. Thank you so much

[hesam_k69]

hi op04 the diameter of coil is 60cm an wire tikness is 1mm resistance is 4.7 ohm i dont know inductane and frequence is about 700 hz .. one thing that i find is when frequence goes up sensitivity to small object also goes up ..one thing that is important is choose frequnce pot from high quality material for frequncy stability also it could be better use multi turn pot for frequency knob for a high resolution resistance change

[GeoMax]

Hi Hesam_k69,

to choose a pot from high quality material is actually not needed. Anyone will do. The key thing in the timing circuit of the TL12000 is to choose a good capacitor type that are temperature stable. That is the key point. Best option for good capacitors are Styroflex capacitors.

[GeoMax]

But thinking about it, it does no really matter what you use for componets... The TL12000 timing does not need to be precise because you are only sampling once and the circuit uses a sample and hold IC. So it does not really matter whether the sampling time varies a little bit due to temperatur instability of a capacitor and/or potentiometer.

[hesam_k69]

But thinking about it, it does no really matter what you use for componets... The TL12000 timing does not need to be precise because you are only sampling once and the circuit uses a sample and hold IC. So it does not really matter whether the sampling time varies a little bit due to temperatur instability of a capacitor and/or potentiometer.

Hi geo thanks for your help My purpose of placing this circuit was to use it for a better design, for example, using a microcontroller, etc., everyone in the forum knows something, let's use the experiences to update the circuit with their help. Thanks

[Op04]

hi op04 the diameter of coil is 60cm an wire tikness is 1mm resistance is 4.7 ohm i dont know inductane and frequence is about 700 hz .. one thing that i find is when frequence goes up sensitivity to small object also goes up ..one thing that is important is choose frequnce pot from high quality material for frequncy stability also it could be better use multi turn pot for frequency knob for a high resolution resistance change

Thanks!!

[durmaz]

[ryy0109888]

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