"How to..." for the TDI, SL & SPP

[KarlS]

Is it feasable to fit a Tone Control to the TDI, SL & SPP? What kind of cost is involved.

Yeah it is, you just have to ask Reg how to put it back as it was first made On the original models,

john

I don't think it would be easy to do on SPP.
Karl

 

[Ridge Runner]

I think the early TDIs have a different layout inside, so that might cause a problem for the later style circuit boards,

 

[rockerfella]

Hi Reg,
Thanks , I will read the 2009 thread. Brian raves about the Folded mono on the TDI Pro Oz
Many thanks for your input
Cheers
Mark

 

[Reg]

The specific design of the audio is different on the SPP and SL than it is on the TDI so adding a tone control would be a real challenge on the smaller units. Personally, I wouldn't even try to do it.

On the TDI, an internal tone control exists. Vr3 is the internal audio tone control that sets the tone and it is located near U5. One could add an external tone control by modifying the existing design but to be honest, I can't tell anyone what would be the best values of components. or exactly how to do it. U5 is an AD654 which is a voltage controlled oscillator.

Reg

 

[Picker]

I was just wondering if anyone can give some feedback on an unmodded TDI pro OZ with the razorback coils. Any differences between it and other coils I.E nugget finders? I have the the TDI PRO oz, unmodded, and no matter what I do I find it does get quite a bit of "chatter" in low conductive mode. This is of course AFTER ground balancing in coarse and fine and AFTER tweaking the frequency knob. Cannot even run it in ALL mode as the chatter is off the charts. I use only nugget finder sadie and 14 x7 so far. Thinking of grabbing a razorback but wondering if it will run quieter. I do find the only thing that quietens it down is by turning the delay from 10Usec to the 13-15 range. It then runs well in low, but am concerned with the delay higher, how will it affect performance? Cheers

 

[grubstake]

I have the the TDI PRO oz, unmodded, and no matter what I do I find it does get quite a bit of "chatter" in low conductive mode. This is of course AFTER ground balancing in coarse and fine and AFTER tweaking the frequency knob. Cannot even run it in ALL mode as the chatter is off the charts. ...I do find the only thing that quietens it down is by turning the delay from 10Usec to the 13-15 range. It then runs well in low, but am concerned with the delay higher, how will it affect performance?

Are you playing around with the settings at home, where the effects of local EMI can overwhelm the machine, or does this happen out in the bush, away from most potential sources of interference?

Also, you don't mention what effect different Gain settings have, although this is very relevant to threshold chatter. Try using ALL mode with 10Usec Pulse Delay and advance the Gain only as far as the threshold stays smooth enough for you.

 

[Picker]

Ok so whats worse, reducing gain or increasing the delay? Both seem to smooth it out. I tend to try and keep gain at max for max depth maybe going about it wrong. Out in the bush, can't get it stable at home to test unless shutting off all appliances.

 

[grubstake]

Ok so whats worse, reducing gain or increasing the delay? Both seem to smooth it out. I tend to try and keep gain at max for max depth maybe going about it wrong. Out in the bush, can't get it stable at home to test unless shutting off all appliances.

Keeping Gain at max won't get you maximum depth if the chattering is uncomfortably high; anyway, Gain is the correct variable for you to adjust. First, fit the coil you want to use, then choose the delay you want and the mode you want, then use the Gain control to achieve a comfortably smooth Threshold with those chosen settings. Pushing the Gain a bit further may be possible if you learn to accept some chattering, but max is unlikely to be achievable. Think of it like the top speed on your car's speedometer dial - theoretical rather than practical.

And if you want an even more comfortable ride, have a look at this start-up guide (don't know where I found it):
whites_tdi_pro_startup_settings.pdf
Be aware that silent threshold involves living dangerously - you could be missing gold and you would never know.

 

[Ridge Runner]

First off, Turn on the machine and put the Gain at 2 or 3,

Set the Pulse to 10

Set the Con Switch to ALL

Set the threshold so it is on the point of going silent right on the edge so you can only just hear it.

Hold the detector at waste high and turn 360 degrees and find the direction where the EMI is coming from and turn the frequency knob to and find the setting where the noise is the Quietest,

Now ground Balance the Machine,

Then turn up the Gain to the point where it starts to run noisy then flick the Con Switch to Low and turn up the Gain where it is on the edge of starting to run rough again and at that point Just Back it off A Touch and then you should be set.

A Slight warble is Ok But you do not want it Oscillating, You might only get the Gain Up to 3 or 5 where you are but as you move out of town you could find that you can Run It as High as 8, 9 or even 10,

The thing with a PI machine is because of the way they work EMI can change from on Hour to The Next, One day I Air tested a Nugget and I could get it at 9 or 10 inches and the next day I was getting it at 13 inches and both days I had the Gain on 10 and I was using the TDI SL which Runs Extremely Quiet and although the EMI was hard to hear The Detector was showing me that it was worse one day than the next, The Weather can have huge effects on PI machines and apart from being able to work in Hot Ground they Bring Very Little to the Table in terms of Detecting, The More Power a PI has the worse it gets, and In Mild Ground with an equal sized Coil a Good VLF will match and in some cases will beat A PI machine when it comes to Depth,

Always keep the Delay set to 10us and seeing as this is new to you set the ground balance up in the normal way, Don't try any of those fancy GB settings try to DISC out stuff until you know what you are doing,

Anyway, Give that A Go and Get back to us and let us know what happens, Just use the setting I have given you and let us know.

Good luck,, John

 

[Picker]

Thanks guys for the reply. Ill give it a go on my prospecting day, Sunday, and get back with results. Still up in the air about razorback coils though. Thing is yes it was a cloudy day. But the freq control is meant to be used to adjust for that and couldn't. So I'd say the problem is more with me being new to the machine by having the following mistakes: gain too high, threshold too high. I've also been reading some great tips from WalnLiz about keeping threshold silent. I was going by the manual and trying to keep threshold above chatter level as it states in the manual pictorial. Obviously by reducing the threshold it may help with chatter so I will try that also. I will be wrapped if I can run it in all mode so fingers crossed.

 

[grubstake]

I've also been reading some great tips from WalnLiz about keeping threshold silent. I was going by the manual and trying to keep threshold above chatter level as it states in the manual pictorial. Obviously by reducing the threshold it may help with chatter so I will try that also. I will be wrapped if I can run it in all mode so fingers crossed.

Wal and Liz have had plenty of success with the TDI and made some excellent videos documenting their techniques (https://www.youtube.com/user/WalnLiz/videos). They've certainly got the runs on the board, so what they have to say about the machine is well worth listening to and learning from, I reckon.

 

[Guest]

I'm glad RR made mention of the weather having an effect on detectors etc. Solar flares are the big impact on this business.

I'll endeavour to find where the site is (I put it up here once, previous to losing the file) and re-post it. It's the NASA site, that has the sun's weather on it and shows the flare activity daily. And there's a certain level over which it is useless going detecting.

 

[Ridge Runner]

Thanks guys for the reply. Ill give it a go on my prospecting day, Sunday, and get back with results. Still up in the air about razorback coils though. Thing is yes it was a cloudy day. But the freq control is meant to be used to adjust for that and couldn't. So I'd say the problem is more with me being new to the machine by having the following mistakes: gain too high, threshold too high. I've also been reading some great tips from WalnLiz about keeping threshold silent. I was going by the manual and trying to keep threshold above chatter level as it states in the manual pictorial. Obviously by reducing the threshold it may help with chatter so I will try that also. I will be wrapped if I can run it in all mode so fingers crossed.

You won't be able to run High Gain in the ALL mode close to Town, because all the EMI but once you have tuned it then switch to High or Low it will run quieter and you will be able to up the Gain a bit even with the TDI SL if the EMI is bad sometimes you have to drop the Gain to around 8, So just play with and worry about learning all the fancy stuff later, 95% of the time the SL runs smooth with the Gain On 10, but it has them extra filters which does spoil you a bit but even on a good day there is less than an inch between the SL and the Pro and the worse the EMI that's when the SL/SPP's take over,

Some days you will be able to run the Pro flat out and then you will see some real depth out of it so stick with it and good luck.

john

 

[Ridge Runner]

I'm glad RR made mention of the weather having an effect on detectors etc. Solar flares are the big impact on this business.

I'll endeavour to find where the site is (I put it up here once, previous to losing the file) and re-post it. It's the NASA site, that has the sun's weather on it and shows the flare activity daily. And there's a certain level over which it is useless going detecting.

The Weather seems to effect PI Machines more than VLF machines due to the power and the frequency used in them, Where as VLFs are more forgiving unless you use Low frequency machines like the GMT and the Gold Bug II, and they can suffer from far off storms, and although they find the smallest Gold they suffer more from the Ground and the weather and EMI, which is why a lot of folks use machine with frequencies between 10 and 18 kHz because they handle it a little better.

john

 

[Guest]

Great John, thanks. This sort of stuff really gives me more confidence with this SL I'm sweating on. About another week or ten days and it should land.

 

[Ridge Runner]

Great John, thanks. This sort of stuff really gives me more confidence with this SL I'm sweating on. About another week or ten days and it should land.

You will be very surprised how smooth the SL Is I have never had to turn mine below 8/10, I wish it had the Pro shaft set up but this way it is very light to swing all day, and they are great to have as a back up if you own a more expensive machine that is effected by the weather or EMI, as it gives you more options and you don't have to call it a day when those sort of things ruin your day.

john

 

[Picker]

Thankyou very much for the great info here by all, including and especially Reg. I am reading the TDI guide (very kindly sent to me) at the moment and am most greatful. Regarding WalnLiz I have watched all their vids on sluicing and crevicing, then on detecting and part of them is what prompted me to get a TDI oz, happy with that as already found a nug.

 

[Picker]

Am liking the part about using the GB knob as a discriminator. Had never occurred to me and have always tried to keep the balance at its quietest. Interesting just to know this little trick, will try it out am wondering if it will make detecting more noisy? Maybe not if coils run along the ground.. Hmm

 

[Reg]

SunriseBoy,

You mentioned you have the SL coming. Did you order it through your dealer in OZ? The reason I mention this is because if it is used, you may run into the hiccup problem.

If it is new and coming via Jimmy Sierra then, hopefully, it is modified.

Reg

 

[Ridge Runner]

The trouble with buying even new machines Is you MUST ask for one that was made in the last 6 months because I bought mine almost 12 months ago, and the Date on the Box says 2012 so I cant bring mine back to OZ unless I want to pay to have the Mods done to it, And When I phoned Whites In Scotland they said they knew nothing about the hiccup/sensitivity Problem and that Whites US had said nothing to them About It, Which to me Is dishonest,
And I am bordering on Cancelling a New machine I have got Coming and buying another Brand, I am Not Impressed,

Why the devil whites have not started doing these mods for the Pro as well Ever Since Reg Solved the Problem For Whites Free Of Charge is beyond me.

john