LOOKING FOR GOLDSCAN 4 Schematic.

[sido]

Hi Reg, following the above post with interest,

Is the TDI similar in circuit layout to the Goldscan IV??

I keep seeing the above referred to the TDI??

Cheers Sid

[Reg]

sido,

The first 200 TDI's were extremely similar to the Goldscan 5 in layout. The later units, the ones with GB ON REQUIRED above the Conductivity switch are different. These later units use a microprocessor to set the timing, thus there is no internal adjustment that can be tweaked to shorten the delay.

White's purchased the rights to the GS 5 and that became the basis for the TDI. That is why there is such a similarity.

Reg

[sido]

Goldscan 5?? I believe the circuit above is the goldscan 4.

What are the differences between the two?

Sid

[Reg]

Geo,

Do you have the original TDI, the later TDI or the TDI Pro?

The TDI pro has two basic changes when compared to the TDI and those changes are the values of 4 capacitors (on the original 200 units) or 2 capacitors (on later units) and moving the internal volume control to the outside. At one time, White's indicated they might provide instructions on how to make the conversion. I am not sure if they ever did that. Maybe Carl will jump in and answer that question.

The changes were made to help with small gold detection and a little less noise from the audio amp.

As for changes, I am very hesitant to offer suggestions that require changing surface mount parts.

Reg

[Reg]

sido,

Sorry about the confusion. You asked about similarities between the GS 4 and the TDI but I misread your question.

This thread is about the GS 4 which was made in the lat 80's and 90's I believe. The Goldscan 5 (GS 5) was built much later, 2005 maybe. Are there any similarities between the GS 4 and the TDI? Yes, some of the fundamental concepts are the same but a lot of the circuitry was changed including the audio. On the GS 4, the audio is a tick tick variable frequency audio, while the GS 5 or TDI has an audio in which the audio level increases as well as a small tone change.

The GS 5 has two channels of information like the GS 4 used for ground balance.

So, there are both differences and similarities. Get to where you fully understand the GS 4 and you will have a pretty good idea of how the TDI or the GS 5 works.

Reg

[sido]

Reg, i am aware of this thread relating to GS4, just was not sure about the reference to the GS5/TDI. Thought i missed something previous in the posts and GS5 got me interested.

I have not seen a Circuit layout of the GS5 and was just asking what the differences were.

All good

Sid

[Reg]

Any GS 5 owners out there reading this thread? If so, interested in adding the single tone mod to your detector? This allows you to select either high conductor or low conductor only or both. BTW, this can be done to the GS4 also.

Reg

[Orbit]

you're absolutely right gs4 can have two tones as tdi !

[Geo]

Geo,

Do you have the original TDI, the later TDI or the TDI Pro?

The TDI pro has two basic changes when compared to the TDI and those changes are the values of 4 capacitors (on the original 200 units) or 2 capacitors (on later units) and moving the internal volume control to the outside. At one time, White's indicated they might provide instructions on how to make the conversion. I am not sure if they ever did that. Maybe Carl will jump in and answer that question.

The changes were made to help with small gold detection and a little less noise from the audio amp.

As for changes, I am very hesitant to offer suggestions that require changing surface mount parts.

Reg

Reg, i have the original. It is the version with the microprocessor for timing.
I added a potentiometer for audio volume and another one for fine GB adjusting as the Pro model.
I am interesting to reject objects with size 2x2x2 cm when i search with the 1x1m coil. If there are 3..4 objects with these dimentions then i have problem. If i will keep the coil 40 cm up of the ground it is OK but i lose depth.

Regards

[Geo]

[ATTACH]22403[/ATTACH] you're absolutely right gs4 can have two tones as tdi !

Orbit this is my TDI at my Lab!!!!!

[Geo]

Reg, i am aware of this thread relating to GS4, just was not sure about the reference to the GS5/TDI. Thought i missed something previous in the posts and GS5 got me interested.

I have not seen a Circuit layout of the GS5 and was just asking what the differences were.

All good

Sid

Sido, here is the schematic of GS 5. I found it here at Geotech and i am not sure if it is 100% OK.

[Orbit]

Orbit this is my TDI at my Lab!!!!!

nowhere I never told that my ,I do not tdi I have a GS 4 ! for now !

[Geo]

Very good machine

[Jose]

Sido, here is the schematic of GS 5. I found it here at Geotech and i am not sure if it is 100% OK.

I hope the day you can see the audio portion.
Jose

[Jose]

Reg, I have a question if you please.
GS4 homemade, has quick response in the audio with a normal sweep speed.
I tried to increase the frequency to 1000 Hz or more, but then the audio is sharper.
I need to change the times constant of the integrator, or other solution exists.
I would appreciate your opinion.
Regards, Jose.