Anyone know the difference between VCO and NORMAL on a Tesoro Sand Shark?

[SADS 669]

The manual doesn't explain why you would use one over the other

 

[Boatlode]

Good question. Terry Soloman told me to always use normal mode, so thats what I do.

Maybe Terry will be along to explain the difference.

 

[roaddust66]

I have several Tesoro machines with VCO/ Normal settling. I never looked a manual and I said " what the heck ! " . Now that I know what it is , I find it very helpful to determine depth. I would call it an audible depth indicator. If the target is shallow , the vco will scream high. If you sweep a target and the pitch does not change greatly , then it is somewhat deep. I am not an expert but hope this helps. I switched from normal to VCO two afternoons ago to listen to a target that was a minnie ball bullet no more 3 inches down and the Tejon's VCO was vibrating the whole detector saying the target was shallow.

 

[Boatlode]

I have several Tesoro machines with VCO/ Normal settling. I never looked a manual and I said " what the heck ! " . Now that I know what it is , I find it very helpful to determine depth. I would call it an audible depth indicator. If the target is shallow , the vco will scream high. If you sweep a target and the pitch does not change greatly , then it is somewhat deep. I am not an expert but hope this helps. I switched from normal to VCO two afternoons ago to listen to a target that was a minnie ball bullet no more 3 inches down and the Tejon's VCO was vibrating the whole detector saying the target was shallow.

But doesn't the size of the target affect the signal strength? I mean, isn't a submarine buried 3 feet deep going to make the machine scream louder than a bullet at 3 inches?


Paging Terry Soloman, please pick up the white courtesy phone in the lobby.

 

[SADS 669]

Great answers, I am off to a place where people swim, so I'll report any finds on VCO or Normal,, thanks for the feed back, Terry, pick up, ( boatlode keeps a grenade handy)

 

[Red_desert]

My Fisher 2-box has VCO, which gets louder as you walk over a large target (such as a pipeline) then gradually decreases if keep on moving. That depends on what you are hunting. From another T-Net member who owns a Sand Shark, he said the VCO helps him to better pinpoint a target, when hunting under the water.

I suppose this is user skill and personal preference as to which mode works best. On my old Garrett GTA 1000, pressing the pinpoint button put you in VCO and produced audible sound which increased as you get directly over the target.

 

[Red_desert]

My Fisher Gold Bug-2 now that I think about it, is VCO in normal mode which can be a faint audible sound on tiny bits of gold. These type detectors tend to scream out over large targets.

 

[SADS 669]

My Fisher Gold Bug-2 now that I think about it, is VCO in normal mode which can be a faint audible sound on tiny bits of gold. These type detectors tend to scream out over large targets.

Thanks for the comments,

Went out today with it, the VCO was really screaming low to loud on all the pull tabs and soda can tops as I moved the head back and forth over them. It did the same with the 12 cents I found too, sigh.

Great afternoon though getting used to the machine.

 

[Boatlode]

Thanks for the comments,

Went out today with it, the VCO was really screaming low to loud on all the pull tabs and soda can tops as I moved the head back and forth over them. It did the same with the 12 cents I found too, sigh.

Great afternoon though getting used to the machine.

Did you notice any difference from 'normal' mode? I haven't ever used VCO mode.

 

[SADS 669]

Yeh, normal mode changes tone when you get a hit VCO screams at you louder and louder as you get over the target. Found out this afternoon.

 

[Terry Soloman]

The Sand Shark has two distinct operating modes: VCO and Normal. When working in the VCO (voltage controlled oscillator) mode, as targets get closer to the coil, the threshold generates a louder, higher pitched tone which is great for pinpointing. The Normal mode works with a single tone and is used for beachcombing and deeper prolonged searches.

 

[SADS 669]

Thanks Terry,

You're the best, I will try the normal mode next trip out to see how that feels

 

[Boatlode]

You da man Terry. Haven't used VCO yet but will try it next time I'm digging a deep target.

 

[DDancer]

VCO stands for Voltage Controlled Oscillator. Its a fancy way of saying all metal mode and performs the same as all metal or pinpoint mode on other detectors. In VCO what occurs is that as a target approaches the coil the increased signal strength stimulates the detector circuits, increases the voltage, and increases the pitch of the tone... just like pinpoint mode does on other detectors. Unlike pinpoint mode, on most detectors, you will have to sweep the detector to produce the tone. I'm not certain if your model uses sweep or has a no-motion mode. Pinpoint mode in most detectors is a no-motion mode.
Normal mode is just a discriminate mode of operation.
VCO will be deeper than normal mode~

 

[Boatlode]

VCO stands for Voltage Controlled Oscillator. Its a fancy way of saying all metal mode and performs the same as all metal or pinpoint mode on other detectors. In VCO what occurs is that as a target approaches the coil the increased signal strength stimulates the detector circuits, increases the voltage, and increases the pitch of the tone... just like pinpoint mode does on other detectors. Unlike pinpoint mode, on most detectors, you will have to sweep the detector to produce the tone. I'm not certain if your model uses sweep or has a no-motion mode. Pinpoint mode in most detectors is a no-motion mode.
Normal mode is just a discriminate mode of operation.
VCO will be deeper than normal mode~

Sand Shark is a PI machine - no discrimination.

 

[Terry Soloman]

...VCO will be deeper than normal mode~

Not in my experience with the Sand Shark. I am much more likely to hear whisper breaks in the threshold while in Normal mode on deeper targets.

 

[Boatlode]

Not in my experience with the Sand Shark. I am much more likely to hear whisper breaks in the threshold while in Normal mode on deeper targets.

DDancer thought we were talking about a discriminating machine in all-metal mode. He didn't know the Sand Shark is a PI machine.

If VCO is deeper than normal mode, I'm not gonna mess with it. I'm already digging small nails at 12". A few weeks ago I dug up a foot long piece of steel re-bar and I could hear Chinese being spoken in the hole.

 

[Red_desert]

If the PI Tesoro detectors still come with a printed spiral coil, that was a coil designed to get small or thin targets like fine gold chains down in the sand.

 

[TwistedElvis]

I always set my SS in (VCO) mode when underwater,

 

[SADS 669]

I always set my SS in (VCO) mode when underwater,

Why??