TESORO GOLDEN SABRE

[simonbaker]

I remember that Goodrat upgraded Compadre to Bandido... you could do the same... sure not an easy task but possible...

Tesoro's of that era are realy similar in schematic.

Or you could made new TGSL... big monster!

The problem is probably at coil: it's hard for people here making good coils for it... expecially with not previous experience in VLF coils.

Kind regards,
Max

Simonbaker, so as i heard Compadre can be modded to work much better.
Open it an make some close photos of its inside.
I heard rumors Compadre is actually sharing same pcb and electronic with some "older brother"...
So ...before you decide to build TGSL first make sure about all the aspects of modding Compadre.
I havent chance to test it and see it so far, except in advertisments..
But...i beleive those rumors are at least half way true.
Regards!

P.S.
Make photos, measure working frequency...
It is possiblle to make much better coil for it and make it hell good, much better than now... Yesterday 06:09 PM

I saw some mods and pictures for the Compadre on this website. They looked like an older version, maybe the one with 7" coil. Mine is new version, 5.75" coil. Inside is surface-mount PCB, everything tiny .

I think I will not mod it for now so I know I have one detector that works for sure . I have to hunt.

Actually, one mod I would consider is making it take different coils -- can't change now. But I don't know what coils would work with new Compadre. Also I don't know what connector would be best to insert after cutting cable -- would it add noise, etc? Tesoro coils are expensive too, almost price of Compadre.

If I build TGSL in pretty box like Ivconic, it is easy to take coil and box off Compadre and put on new coil and box for TGSL, maybe I could use the pole for both as I feel like .

I don't mind difficulty of building TGSL, not afraid if it doesn't work. A good project thanks to everyone here who did very good engineering.

[ivconic]

Also instead of trimpot 100K (threshold) between +8/-5V there
is 330K connected directly to -5V. Did you find this value to be
good enough and there is no need to place trimpot?

Speaking of this there are 2x100K (R48 and R51) used instead of just one
200K. Can I use 200K instead, 0.25W. Perhaps they need to be 0.5W, i dont have a clue why did you switch those

Yes, schematic was drawn before latest mod appeared. I left treshold as it was at that version. Actually no need for threshold preset anymore, yet you can apply it and see how it performs, good for experimenting. 330K is original from TGS schematic, working just fine.
I couldnt find 200K (hard to find in shops here) so i put 2x100K.
1/8W are just fine.

I already mentioned 1K missing resistor on pcb. Read previous posts...

My present pcb are as shown on draw. Mod is applied as piggy pcb over main. Threshold is fixed - 330K and 1K is added over...
So...nothing changed. Be free to make it that way or any other way that suits you.
Regards!

[ivconic]

Im checking the PCB you use :

1)R13 and R14 (connected to RX leads) which on the schematic are 5K1
on the board are marked as 4.7K;

2) R27 (1K) is missing on the board

5K1 are also hard to find in local shops, so i am using 4k7...

[eclipse]

Thank you for the replies, ivconic
Cheers!

[Max]

I saw some mods and pictures for the Compadre on this website. They looked like an older version, maybe the one with 7" coil. Mine is new version, 5.75" coil. Inside is surface-mount PCB, everything tiny .

I think I will not mod it for now so I know I have one detector that works for sure . I have to hunt.

Actually, one mod I would consider is making it take different coils -- can't change now. But I don't know what coils would work with new Compadre. Also I don't know what connector would be best to insert after cutting cable -- would it add noise, etc? Tesoro coils are expensive too, almost price of Compadre.

If I build TGSL in pretty box like Ivconic, it is easy to take coil and box off Compadre and put on new coil and box for TGSL, maybe I could use the pole for both as I feel like .

I don't mind difficulty of building TGSL, not afraid if it doesn't work. A good project thanks to everyone here who did very good engineering.

Hi,
about connectors I use these you can see at Maplin:

http://www.maplin.co.uk/Search.aspx?...y%20Connectors

Are multiway, low frequency connectors.

You can mount the socket on panel and then wire cable to the plug: they are good cause you fix the plug with a ring-screw after inserted in socket... much like Tesoro's original plugs do (though Tesoro's use bayonet mount).

The 4-ways kind are good for coils like TGS.

They cost few... and are strong enough for MD applications... though are more exposed to corrosion... than some original MD parts.

The noise is not a big issue in these connectors if wiring is done right way: There's no difference between Tesoro's ones and these about noise at these low frequencies.

From what I know some small manifacturers prefer using these than more fancy things... in PIs too... cause are excelent for the purpose and costs are reasonable.... and are worldwide available.

Kind regards,
Max

[nakky]

Hi Max ,Minelab using these conectors.Grt Nakky.

[nakky]

And I

[ivconic]

Yes that is the one i am using also...

Some benefits in S/N relatio also can be achieved if connector is mounted as close as possiblle to pcb with short leads. Front panel wit pots and switches is also grounded.
Keep in mind that all grounds are better to be connected in only one spot...due low frequency and possible some sideeffects. How to do that? Depends of your exact setup; enclosure,front panel,small back panel with coil connector...that's why i copied exact Fisher 1265 setup. Turns to be very eficient!
Also noticed that Disc/All switch is better to be wired with very small(thin) coaxials...taken from some taperecorder head Reduces S/N also. But also all 3 cable shields to be connected at one side only and one spot. On other side keep them short in coat and unconnected, only "hot" ends to be connected to switch pins.
There are many small tips very influencing S/N relatio and should be applied when mounting detector finally.
More you pay attention on those - better performances you will get... simply as that!
Regards!

[Max]

Hi Max ,Minelab using these conectors.Grt Nakky.

Hi,
yes, right... I forget these... ML ... Coiltek use them too... with a black cover on rear... that made them look different but are exactly the same stuff.

Tesoro's, instead used on uMax coils the bayonet ring and conic pins inside... I must say... I like more the ML's way for that, though Tesoro's works too and well.

I like cause it's easy to replace and also for making new homemade coils... you find that connectors everywhere for cheap!

Kind regards,
Max

[ivconic]

Disc and Sense pots turned to be pretty immune on intermodulation so i wired them only with single wires (plastic coat).
Next step (until winter) is to draw new pcb (also 1265 look like) but with layout so suitable to have traces from component place to front panel, to void using long "air" wires for connecting.
I already analyzed how to do that. Wont be easy. Disc and Switch pads are far away from front panel side...hmmm...will need very thin and good gnd surrounding from exact pads all the way to front panel. Across the pcb will need also to void all the "hot" spots. Need very pationate analyze and lot of work. But i intend to do it until winter...

[Max]

Hi Ivconic,
I mounted the monostable in my TGS, the one for field use... and it's good!
I get much better performances on deep stuff... tested in test-garden over stuff at 30cm to 35cm deep... small stuff... 1 eur. Works good.

Till now I can detect 1 eur at 30cm loud using just my heavy modified bandidoII, but with TGS I always had troubles with it cause of very weak signal at both speaker and headphones...now it's really different. The bang it gives now cannot lead you miss it !

Actually, I tested device on 32cm and works too... even if need more care e.g. about distance between coil and soil.

But there soil it's easy... then I moved away a bit...

I also checked other stuff like GEB and here are the problems: as expected I had lot of troubles with geb tuning using the monostable...so I had first to try find a perfect geb tuning in normal mode...cause

if not PERFECT GEB tuned ...any movement respect to soil will cause a loud beep...using monostable and that scary me about using on real field: the geb tuning is so critical on TGS! changing it often due to soil changes , when you walk away...is so time wasting !

What about your tests ? Do you experience the same with monostable on ?

Ivconic... another good question is... how do you tune geb at searchfield... do you use the ferrite or just soil... bobbing up and down the coil ???

I noticed a big disvantage in TGS about that respect to BandidoII... in BandidoII is suggested by manual using motion mode for GEB tuning: in that way is the same as tuning TGS (that's only motion machine), and require lot of time.

But, I usually use the all-metal/pinpointing mode on bandidoII (non-motion) to achieve perfect geb tuning... that's easy and fast there... once threshold is set you must reach a point where lowering coil to soil give no change in intensity...
That really save me lot of time... respect to disc mode geb tuning...motion kind.

Have you any idea about GEB tuning saving time on TGS too ?

Kind regards,
Max

[ihsjepsen]

Great Stuff

I've been lurking here for over a year and have finally decided to get involved in this thread. That is if the active members will put up with a newbie that does not ask a bunch of questions with out searching the threads first.

IHS

[ivconic]

Hi Ivconic,

I mounted the monostable in my TGS, the one for field use... and it's good!
I get much better performances on deep stuff... tested in test-garden over stuff at 30cm to 35cm deep... small stuff... 1 eur. Works good.

Till now I can detect 1 eur at 30cm loud using just my heavy modified bandidoII, but with TGS I always had troubles with it cause of very weak signal at both speaker and headphones...now it's really different. The bang it gives now cannot lead you miss it !

Actually, I tested device on 32cm and works too... even if need more care e.g. about distance between coil and soil.

But there soil it's easy... then I moved away a bit...

I also checked other stuff like GEB and here are the problems: as expected I had lot of troubles with geb tuning using the monostable...so I had first to try find a perfect geb tuning in normal mode...cause

if not PERFECT GEB tuned ...any movement respect to soil will cause a loud beep...using monostable and that scary me about using on real field: the geb tuning is so critical on TGS! changing it often due to soil changes , when you walk away...is so time wasting !

What about your tests ? Do you experience the same with monostable on ?

Ivconic... another good question is... how do you tune geb at searchfield... do you use the ferrite or just soil... bobbing up and down the coil ???

I noticed a big disvantage in TGS about that respect to BandidoII... in BandidoII is suggested by manual using motion mode for GEB tuning: in that way is the same as tuning TGS (that's only motion machine), and require lot of time.

But, I usually use the all-metal/pinpointing mode on bandidoII (non-motion) to achieve perfect geb tuning... that's easy and fast there... once threshold is set you must reach a point where lowering coil to soil give no change in intensity...
That really save me lot of time... respect to disc mode geb tuning...motion kind.

Have you any idea about GEB tuning saving time on TGS too ?

Kind regards,
Max

Hi,Max!
I know what are yoy saying. TGS could be pretty unstabile if GEB is not adjusted critically.
I am using trimmer for GEB not potentiometer. Once adjusted well it stays inside preseted for good.
I do not adjust it anymore. If i face some high mineralisation on the field, only way to make TGS calm is to reduce sensitivity.
For example if Sense was at "8" and after few meters,walking, suddenly starts "beep"-ing or chattering due differences in soil conditions i am lowering Sense let's say to "7" or "6" and it calms down and retreive perfect stabillity.
After a while do recheck if it's gonna be stabille on "8" or more again.
But these are very rare cases. In every 10 terrains only one is so "trashy" to provoke TGSL to work erratically.
This behaviour is tied mostly to coil and its design. I noticed different behavior with few different coils.
How i adjust Geb? I have ferrite rod, hot rock, black sand and few old irons in my workshop. I adjust Geb with trimmer not to react on those items yet to react on thin silver piece. It is criticall, cometimes it makes difference in 1/2mm on trimmer...That's why i do not use potentiometer and cables to connect it with pcb..only trimmer.
My field experiences with this mod are very good. Yes it can bang pretty loud if Sense is at maximum and suddenly you pass with coil over some highly mineralized area. But lowering Sense to "6" (for example and passing again it will remain silent. Also switch is very usefull here. In case you come to very trashy field and oftenly have loud bangs there you can easilly switch Off monostabile mode and continue to work without it...rare cases.
Regards!

[ivconic]

Not a real problem at TGSL, only if coil was made and nulled properly.
Much better stabillity and accuracy than many other todays models.
For example i will take Minelab Advantage. Just rise Sense pot at maximum and try to work with it! Hell! Impossiblle! Advantage will give constant falses all arround! You must lower Sense to "8" and even "7" to make it calm and stabille.Even than Advantage can produce ocassionall "mums" without obvious reason. Adjusting like that Advantage goes much more shallow than TGS adjusted to be 100% stabille. This is already tested and proved. I did same test and comparsions many times in the past...without and recently with this latest mod. TGSL is winer in all; depths,disc and stabillty.

But...coil,coil and nothing but the coil! All problems came and ends to damn coil! You must pay efforts to make very good coil for it.

[eclipse]

yes the musketeer with 10" coil can detect a coin
in ground around 23-25sm, even if you have to lower
your TGL sense, it probably still will be the deeper detector.
and you can still hear from time to time false beeps with the advantage,
not a pain to die..