TGSL help

[metaldetector107]

Hi all
i have tested my tgsl today the sound not stable it is like tak tak tak tkkkk olso doesnt detect anything when i move the tx rx coil the sound changes but still not detecting i am using 741 instead LM308 so please help me
please note i have connected the 1k missing resistor after 22n and +8

thanks again

[barry]

Only post your question in 1 forum. Don't spam up multiple posts with the same question.