For those of you unfamliar with the "twitch"..

[Uncle Willy]

This is a procedure to generate a good signal from a bad signal. Minelab users call it the "wiggle" but I call it the twitch because that is what it basically is.

When you get an iffy signal hold the coil over the target and twitch it rapidly from side to side in short strokes.. A good signal will produce a belltone or beep for a nickel. A bad target will give you the iffy signal. End of lesson.

Bill

 

[John-Edmonton]

And it works good too

 

[Wisconsin Pete]

It don't matter what you call it, as long as the method produce's the PRIZE

 

[Dirt NC]

Thanks for the info Bill. I know that works on a DD coil like on my soveriegn but didn,t realize that the same jitter would work with my gtp 1350. Can't wait to try that out!

 

[DavHut]

Thanks Bill. Thats something else than I imagined, sO stand corrected on my previous comment about it.
In the end I get the same result, but your twitch is a different matter...

 

[Uncle Willy]

Yeah it turns a lot of bad targets into good ones.

Bill

 

[Uncle Willy]

It would appear that way when watching someone jerking their detector back and forth. People probably think I've got palsy. But it produces coins. Here awhile back I picked up four corroded dimes next to a picnic table that gave real iffy one-way signals until I twitched them.



Bill

 

[Uncle Willy]

Did you turn some bad signals into good ones? Works great on corroded coins that don't want to produce a full signal.

Bill

 

[Uncle Willy]

One has to remember that we are all using motion detectors and motion is the key word. That's why if you whip the coil they will go deeper and discriminate better and this part applies to twitching. If you whip the coil over the target it can then see a coin that was only partially visible to it before.

Bill

 

[Mick in Dubbo]

Why does moving your detector faster, give more depth and better discrimination? It sounds counter intuitive.
Mick Evans.

 

[Uncle Willy]

That's the way motion detectors are designed. You can scan at any speed you wish from rapid to near non-motion. That's why twitching turns bad signals into good ones. With a motion detector you can't hold the coil stationary over a target and maintain a signal. The coil has to be moving, even if just a little. The Sunray Probe is just a tiny motion detector. If you hold it still over a target you get nothing. Move it and it signals. Move it fast and it goes deeper.

They had to design them this way to get more accurate discrinination, response and recovery, and to not miss targets. You'd have to talk to an engineer to get all the whys and wherefores.

Bill

 

[Mick in Dubbo]

Thanks bill. Thought it might be a bit too technical a question. I've noticed that you can swing the 250, a smidgen faster than 2 seconds for a 4 foot sweep, but if you do the same swing in 1.5 seconds, then you miss everything.Only a swing speed to use when in trash free areas, looking for them coin patches.
Mick Evans.

 

[Uncle Willy]

Yeah the 250 has a rapid response but you can fool it with to fast of a sweep. It's also guilty of backshooting if you swing to fast.

Bill

 

[Mick in Dubbo]

Please excuse my ignorance. What is backshooting?
Mick Evans.

 

[DavHut]

Or wear steel toed shoes while detecting!

 

[Mick in Dubbo]

It's funny how language can be used a bit differently in different parts of the world. Here in Oz, we'd say "that it can back-fire on you."
Mick Evans.

 

[Uncle Willy]

Not quite the same. Backshoot is when you get a junk signal at one end of your swing and it repeats at the other end of your swing although there is nothing there. Sort of a delayed double response to the same target.

Bill

 

[Uncle Willy]

Just explained it.

Bill

 

[Uncle Willy]

That'll do it.

Bill

 

[Mick in Dubbo]

n/t