TDI question for Reg

[Frank-S]

Hi Reg. Do you know if White made any changes in the SL TDI.
This is my second SL It will not do what my first SL would do.
1) First SL came with 12'' coil, i did not like coil, poor depth,no good on small gold.
I have a small coil about 7'' i call it a mono coil its not.Dave Emery gave me the idea
years ago I don't know Dave,only talked with him.
I tried the 7'' coil on my first SL TDI, IT worked good,good depth,good on small gold
would even detect gold dust in a vial.
2) Second SL. I tried the same 7'' coil on second SL the one i have now the coil will
not work wont come on.The 12'' coil works, the DOD coil i made works.
Both SL TDI look a like have same name,but are different detectors.
White must have made a change in side detector.
Frank.

 

[Reg]

Frank,

I suspect something is wrong with your 7 1/2" coil because if your 12" coil works, then the smaller coil should work. There have been no changes that I know of to the SL that would cause a coil to not work.

Reg

 

[Frank-S]

Thanks Reg,
There's nothing wrong with 7 1/2 coil,it works on my modified piranha pi
It worked very good on my first TDI.
I can now get it to work, not very good.
On the first TDI, I wired it like this (connector) pin 5 ground to one side of coil
pin 4 to other side of coil,coil worked very good.
TDI that i have now,coil wired the same way will not work.only get threshold sound.
To get the coil to work on the TDI that i have now, it has 2 grounds pin 5 and 2
put pin 5 and 2 on one side of coil pin 4 to other side of coil,it works not very good.
White made a change from first SL to the one that i have now.They are two different detectors.
If i remember correct there was a problem in Australia with SL and White mad
some kind of a change.
Frank.

 

[Reg]

Frank,

The Australian problem had nothing to do with coils. I know, I came up with the solution which required some internal mods to the SPP. The problem there was what was referred to as a "hiccup" type signal after going over any sudden ground change or target.

Your complaint pointed out something I never realized and that is, the TDI and SL ARE NOT !!!!!! WIRED THE SAME ON THE COIL CONNECTOR inside the control box. This is STUPID!!!!!

As for your coil, DO NOT TIE 2 AND 5 TO GROUND AT THE SAME TIME!!!!!!!! Tie 5 only to ground on the TDI. Tie pin 2 to 4 only. On the SL, Pin 2, 3 and 4 are tied together and tied to ground in the control box.

Pin 4 is the TX signal and Pin 2 is the RX signal on the big box TDI's, but on the SL, things are different. Keep this in mind!!!!!

So, on the SL, they seem to have managed to get things reversed (or back asswards as I would say) and there they tied pins 2,3, and 4 together and these three pins are tied to ground. Pin 1 is the receive signal and pin 4 is the TX signal.

Right now, I have no idea what they are doing on their coils as far as the connector wiring. I am guessing they are the same but I don't know for sure.

Reg

 

[Reg]

Well, I have egg on my face on my previous statement. Fortunately, Carl M set me straight and pointed out something I missed and that is, the layout of the wires on the board are not the same as on the connector. So, White's does have the connector wired the same on the SL as what is found on the TDI.

I really have to quit looking at things when I am tired.

Sorry for the confusion and I apologize to White's.

Reg

 

[Frank-S]

Thanks Reg,
Mono coils are easy to wind, so I wounded 2 mono coils one same inductions
and second coil higher inductions.they both work same- no good.
From what you said, I have the connector pins right.
For now i am going to put the SL IN the closet, and tell my friends not
to purchase any new White SL .The first SL that I had the mono coil worked.
Frank.

 

[Reg]

Frank,

The pinout numbers I posted a couple of posts ago were the pin numbers of the pc board and not the coil connector. So, no, you do not have the coil connector pin connections right. As I said before, do not tie pins 2 and 5 together in the connector.

All coil connectors are wired the same whether the coil comes with a TDI or a SL. Pins 1 and 5 are shields or grounds. Pin 2 is the RX and in the coil connector this needs to be tied to pin 4. Pin 4 is the TX signal and on a mono coil needs to be tied to Pin 2. Again, this is the coil connector pin layout.

Reg

 

[Frank-S]

Reg. on the first SL that I had my mono coil only has 2 wires,I tied one end to pin 4
and other to pin 5. SL and coil worked very good.
The SL that I have now I tied end of coil to pin 4 other end to pin 5. wired the same
this Sl did not work. Both SL's have same name,but work different.
You said to tie pin 2 to pin 4 on one end of coil and other end of coil to pin 5.
I hope this works, all I wont is to have this SL work as good as first SL even if its
connected different.
Frank.

 

[Reg]

Frank,

Your SL coil had to have had Pin 4 tied to pin 2 to work. You may have not had to do that because it was done by the factory. So, if you tie pin 2 to pin 4, it will be just like what the factory does and should work.

Reg

 

[Frank-S]

Reg
I will give it a try.
Frank

 

[Frank-S]

Reg.
I tied pin 2 to pin 4.it does work better,but not as good as the 7'' coil did with my first SL.
With SL I have now 7'' coil, pin 2 and 4 tied together it detects my test nugget at 1 inch
a US nickel at 9 inch.
My first SL ,same coil same test nugget.the first SL would detect my test nugget Way More
than 4 inches don't remember depth on nickel.
White has made a-lot of changes from first TDI. What they selling now is not top of line detector
the last 2 SL pi with 12'' coils have poor depth. It will not detect my test nugget,only detects a US
nickel at 11-1/2 inch. not good for a top of line pi.
Think back about 13 years you modified one of Eric early detectors for your Father and helped me
modified my pi, my pi at that time would only detect a nickel at about 5'' did not detect my same test
nugget.My pi had a 10 coil.After I modified my pi with your help.it detected my test nugget at 3-1/2''
and US nickel at 15''. if I remember right your Father pi would detect a nickel at 18''.
The SL has a 12'' coil wont detect my test nugget,detects a nickel less than diameter of coil
not good for top of line pi.I will stop there. serial numbers of both SL.
My first SL #3141 3322 034 AOD-I last four might A0D-1
SL I have now #4365 3322 005 80 BC
Reg thanks for your help.
Frank.

 

[Reg]

Frank,

I have never looked at the White's connector, so I don't know what type of wiring they use. If they use a two conductor wire and not a single conductor with a shield, then the two wires may be reversed. The shield shouild connect to pin 5 and the TX signal should connect to pin 4. If both wires are plain wire inside the White's connector, then they may be reversed, meaning the shield is connected to pin 4 and the signal to pin 5, If this is the case, then the depth loss you experience may be the result of the wires crossed.

So, you might swap the wires on pin 4 and 5, making sure you leave the jumper from pin 4 to pin 2 and see what happens.

Reg

 

[Frank-S]

Thanks Reg
White made a lot of changes scene first TDI,weight, battery, noise who knows what other changes.
The SL don't have enough power for the 12' coil,if a top of line pi made to prospect wont detect a gold ring
size of a US nickel or a nickel, 3''inches or more than diameter of its stock 12'' coil, it needs more power.
The SL needs a increase in volume,gain and lower us. I believe that my SL is not going down to 10 us I
have no way to test.also not enough gain.
SL has enough power to prospect with a 4 or 5'' coil but not a 12'' coil.What can you expect to find with a
4 or 5'' coil.On East coast of US it cant compete with top of line VLF detector not much black sand here.
West coast SL will shine works good in black sand, but 12''coil has poor dept.
We both had a pi with a 10'' coil that would detect a gold ring or US nickel a 15''.
I am disappointed with my SL. White needs to work on its TDI.
Thanks again for your help.
Frank.