no sound..please help seniors and guru's..

[jladre]

This is my first time to build a vlf type detector.. can we get any sound from the speaker of the completed board without coil attached?? I finished one but i think it is not working , i cant heard any sound..

[WM6]

First finish your detector, check your work a couple of time again before power on and then start alarm of non-working.

If you have audio battery check in your design, then voice should be heard at power on, even with coil disconnected.

[jladre]

First finish your detector, check your work a couple of time again before power on and then start alarm of non-working.

If you have audio battery check in your design, then voice should be heard at power on, even with coil disconnected.

Thanks WM6 now i know my board isn't working.

[Silver Dollar]

Well you need a coil to test. The TX oscillations create the square wave for the sound output....

[jladre]

Well you need a coil to test. The TX oscillations create the square wave for the sound output....

Thank Silver dollar i gonna do that..

[jladre]

still not working... in all ic's excpt 4020 i got a + 8v in pin 8 and pin 7 in opamf..but in all pin 4 i only got.73 volt.. im using. Ne5534 in replace of lm308.. would it be the culprits? Or it have some other suspects?

[jladre]

Problem solve..it just a transistor markings in bord are reversed.. my tgsl is working now but a very low depth..

[paku]

How Many Voltage You Get From TX And RX

[jladre]

How Many Voltage You Get From TX And RX

I got tx 27.7mV and rx 49.2mV..is this right?