TESORO GOLDEN SABRE

[golfnut]

The one you made which shifted during potting - have u tried using it - it may be ok in use.

If u make more, dont go for an absolute null, the important factor is the phase relation between Tx and Rx signal.

When good, u can get rid of ferrite. Then you will be away ( oh and single beep not double with unclad coin )

[der_fisherman]

Glueing Coils Down

We don't have silver coins in last 70 years so ...
must stay away from trashy areas

I have another problem
I used epoxy and it shrunk coils unbalanced them
Building another pair

We have all made this mistake!!

But there is a relatively easy way to avoid it.
Roughly adjust for null.
First glue down say 50-75% of each coil. Keep scope attached while doing this. If ye if you mix too little.....if you mix too much, do not use it, simply throw it away. Mix the minimum each time or less and do it twice if you mix too little....
Let epoxy dry/harden.
Adjust for null.
Glue 50% of what is left unglued.
Let epoxy dry/harden.
Adjust for null.
Glue 50% of what is left unglued.
Let epoxy dry/harden.
Adjust for null.
And so on........
This will get you close to a perfect null adjustment I find.

I like epoxy due to it being waterproof etc., so don't give up on it too quickly....sadly it is heavy, so do not use huge amounts....

I hope this helps

Regards

Andy

[sdesic]

Is there a way to reuse coil envelope which is glued with "epoxy" ?
I used strong glue in form of a silicone - corpus is ABS so no acetone.

[sdesic]

We don't have silver coins in last 70 years so ...
must stay away from trashy areas

I have another problem
I used epoxy and it shrunk coils unbalanced them
Building another pair

[satdaveuk]

To put it in a nut shell discriminate foil and you loose silver such as pre 30s old six penny bits etc

[sdesic]

Discrimination Charts

[sdesic]

I was testing TGSL this weekend and I went to trashy area (foil, iron, pate "cans")
Tried to disc out most of that but I was unable. Mosquitoes attacked me also so I left.

Foil and iron are not so much of a problem disc is on middle position.

When I discriminate foil, what am I missing?

Some of gold stuff ... not zinc and nickel

Pate cans replaced iron bits


Nemesis

[der_fisherman]

Null phase
[ATTACH]30387[/ATTACH]

The picture is great - better than a foto from a normal scope I feel!!
The USB Scope appears to be working really well.....
regards
Andy

[sdesic]

Null phase

[sdesic]

TGSL test points 1, 2, 4, 5 (gate TR4 and gate TR5)

[der_fisherman]

Hantek USB Scope YouTube videos

I found some YouTube videos or this product for anyone interested, check here:-

https://www.youtube.com/watch?v=m1WVZf5cuQE&hd=1

https://www.youtube.com/watch?v=ZvHAlTTriwY&hd=1

Looks to be a solid well built piece of kit, the 2 x probes alone might cost about the same as the whole unit on ebay!!

The first video picture is a bit fuzzy, but you can see the PC display and it looks excellent. The second is Spanish I would guess, but the video quality is far far better.

regards

Andy

[der_fisherman]

I have this scope Hantek6022BE PC USB 2CH Digital Oscilloscope 20MHz 48M.
I have not used it much so I can't tell you anything ... from its info I bought it and it should be fine for our work with detectors.
Don't have any experience with real scope and I have some usage of audio card scope
(managed to repair TGSL with lots of help from friends from geotech).

Hantek6022BE sells about 65$ US on Ebay with postage so I think it is good choice.
I am planing to use it to adjust this TGSL and its coil.

Good solid feedback, many thanks.
Please continue to keep us posted.
Pictures, if possible, would be fantastic too.....
Best of luck and thanks again,
Andy

[sdesic]

If you have any test for it I can do it for you and post screenshot here.
I am using it with mini laptop - working on batteries.

[sdesic]

I am very interested for a friend of mine as to which USB scope you have, how well you get on with such a scope and if you used a normal one BEFORE you got the USB version? As with previous experience on any scope, your replies could be very helpful for others here without a normal scope!!!

Please chime in anyone else who has USB scope experience with full details as you see them including make, model and price/cost if you built it from parts or even a kit.

I personally imagine that such a device, properly made, would be really useful for setting up any low to medium speed signals like a metal detector for example.....in fact anything within the audible frequency range up to around 16Khz (for younger members at least!).... But it would not surprise me personally for a well designed USB scope to be usable far above this frequency.

Also, anyone using a PC Sound card scope, should also chime in with their experiences too as they will probably be even cheaper to make even than a USB version....

Thanks to all
Andy

I have this scope Hantek6022BE PC USB 2CH Digital Oscilloscope 20MHz 48M.
I have not used it much so I can't tell you anything ... from its info I bought it and it should be fine for our work with detectors.
Don't have any experience with real scope and I have some usage of audio card scope
(managed to repair TGSL with lots of help from friends from geotech).

Hantek6022BE sells about 65$ US on Ebay with postage so I think it is good choice.
I am planing to use it to adjust this TGSL and its coil.

[der_fisherman]

USB Scope questions!!! (and sound card scopes too!!)

I am fine with device, only problem for me is tricky adjustment of phase or null.
Now I have oscilloscope (USB PC oscilloscope) so I hope that I can get more from it.
Thank you manny77.

I am very interested for a friend of mine as to which USB scope you have, how well you get on with such a scope and if you used a normal one BEFORE you got the USB version? As with previous experience on any scope, your replies could be very helpful for others here without a normal scope!!!

Please chime in anyone else who has USB scope experience with full details as you see them including make, model and price/cost if you built it from parts or even a kit.

I personally imagine that such a device, properly made, would be really useful for setting up any low to medium speed signals like a metal detector for example.....in fact anything within the audible frequency range up to around 16Khz (for younger members at least!).... But it would not surprise me personally for a well designed USB scope to be usable far above this frequency.

Also, anyone using a PC Sound card scope, should also chime in with their experiences too as they will probably be even cheaper to make even than a USB version....

Thanks to all
Andy