Problem with My TGSL!

[simosner]

Hello,
I am new to this forum and I have the honor to request you to help me, I just get tocomplete my first detector TGSL. When I connect with the battery gives a beep But the problem is that after the test gives no dial tone.

Below the image of the oscilloscope :





Ch 1 (J1) (5V/Div) & Ch2 (Pin 7 U101a) (5V/Div)


Ch 1 (J1) (5V/Div) & Ch2 (Pin 6 U101a) (1V/Div)

[Qiaozhi]

Hello,
I am new to this forum and I have the honor to request you to help me, I just get tocomplete my first detector TGSL. When I connect with the battery gives a beep But the problem is that after the test gives no dial tone.

Below the image of the oscilloscope :

The problem appears to be with the coil balance, as the output of the preamp (U101a pin 7) is saturated. Please give your coil details.

[simosner]

The problem appears to be with the coil balance, as the output of the preamp (U101a pin 7) is saturated. Please give your coil details.

104 windings for RX and 99 windings for TX.
Diameter: 255mm x 137 mm (one coil).
Wire size: .25mm (30 AWG) enameled.
Tx resistance: 24 Ohms.
Rx resistance 25.5 Ohms.

[Qiaozhi]

104 windings for RX and 99 windings for TX.
Diameter: 255mm x 137 mm (one coil).
Wire size: .25mm (30 AWG) enameled.
Tx resistance: 24 Ohms.
Rx resistance 25.5 Ohms.

Try changing the coil overlap while monitoring the preamp output.
Have you read this yet? ->
http://www.geotech1.com/forums/showthread.php?t=15710