Issue with Minelab Sovereign GT

[antalaz]

Hi all,

I've got problem with a Sovereign GT.

At the beginning, the sensitivity pot was swifting the treshold setting. By increasing the sens, the treshold became unreachable.

Got rust on power supply connections, I've cleared it by resoldering, and now everything is mute. i can just hear the first *beep* at startup.
If I play with treshold pot nothing happen, no sound, even by playing on sens pot.

Could anyone help me or got the schematic to lead me ?


Best regards

[kt315]

what batts holder and batts you use?

[Andi68]

Unsolder and measure the pot, even while turning

[Math]

hi, i had similar problems with threshold shifting and becoming erratic when turning the pots on my XS2A
i found it to be the solder joints at the back of the front controls pcb touching the front plastic panel with the pots on
its spaced with plastic washers behind each pot shaft about 1mm thick, i changed them for thicker 2-3mm O-rings
this did the trick.. it requires removing that front controls pcb to fix the problem
im not sure if the GT and Elite are similar in front panel design to the XS2s

[antalaz]

HI,

Firstly thank you all for your responses !

What i did those last days:

- Wire channel checked and changed
- Threshold pot changed
- I've tried several different power sources (even a stabilized generator)... same result

I'll check my front plastic panel as Math said, will get back to you when it's done !

Thank you again

[kt315]

clear gaps around all pots' pads on front panel. ML uses very tiny gaps pad-polygon.

[kt315]

on front panel pcb***

[Andi68]

With these old devices the pots, switches or Elkos / Tantals are the most common sources of interference

[antalaz]

I've changed all switches and tantals. Startup *beep* is more loud and clear. Also tried to space front panel. Still searching for fix..

Here's a picture of the spot where we can measure the output voltage of the threshold pot



thanks you all for your reponses

[kt315]

I've changed all switches and tantals.
---
I DID NOT WRITE CHANGE SWITCHES AND TANTALS - !!!
you must CLEAR the board in place POTS PADS-BOARD COPPER.



or desolder wires from pots and measure pads with GND and +E on connection.

[antalaz]

Problem solved !! it was the volume potentiometer: bad connection.

thank you all for your help

Best regards

[Andi68]

great