Vaquero?

I can't even spell "Tesoro", but I do know that they are considered "silent search" machines. That means no threshold in disc mode to me.

I'm pretty sure you'd have to ground balance it in AM mode. I don't know any other way.

Perhaps, Ski will come along and straighten us both out.

Yes you ground balance a vaquero in all metal mode. Set your sensitivity to 8-9, your mode to all metal, adjust your threshold, then adjust your ground balance.
I don't see the problem. Once the ground balance is set in all metal mode, is it not still balanced when you switch to discrimination mode?

Rebel said:

I have been told that the threshold and manual ground balance only work in the all metal mode and not the disc mode. Is this correct? If so, what real good are they as most people will have at least some disc set 90%+ of the time won't they? Why not just use a Silver UMax?

Click to expand...

Usually that is how it works.

The all metal, non-motion, channel is electrically what we call DC coupled (that is why it works without needing coil movement and why it is sometimes called the DC channel). As such, it needs ground balancing to avoid it creating an offset signal.

The discriminate channel normally goes through some electronic filtering to separate the target signal from the ground matrix signal. In this filtering process the signal becomes AC coupled to the downstream electronics. Another way of saying this is that slowly varying signals can't get through the filters. This is also why discrimination requires constant coil motion. So, since the discriminate channel is AC coupled, it doesn't need to be balanced against the ground since the ground signal is pretty slow changing and can't get through the AC coupled filters.

Sorry if the above is still too complex. I tried to make it as simple as I could without getting into filter theory.

Thanks to evryone

that has replied.

I believe that the ground balance on the Vaquero is tied in with the all metal and the disc. mode. Threshold is an aid to help pinpoint and if you turn the threshold up all the way it is called "super tune" (Tesoro talk) which give some extra depth. Steve.