Compadre Schematics

[simonbaker]

Have you considered that the Compadre is perhaps just not as sensitive as some of the other Tesoro detectors?
Have a look at the attached chart:

Great chart, thanks!

Of course I'd like to milk as much as I can out of the cheap detector (isn't that what mods are all about?). But mainly I'd like to understand the pots so I'm not making it worse instead of better.

Always appreciate your excellent info.

Regards,

-SB

[Steve in MS]

The 2 pots at the bottom, one is for tuning the discrimination and the other is for ground balance. I'm thinking you may could tell which of the 2 are the disc setting by seeing if the wires go to the knob control. I had a gentleman tell me that the disc pot could be altered and you would affect the high range and the low range, in fact he had altered it so that the high range would knock out the dime/ penny, that way he could cherry pick quarters. If you adjust them, make sure you mark them first and use a screwdriver recommended for adjusting pots and don't touch the components on the circuit board. I did ask him how one would adjust the GB but he didn't have the instructions to do that. Oh yeah, the Compadre has the 180 disc, not 120. If you turn the disc all the way down, it will give a strong signal on nails.
There are 2 reasons why the Compadre doesn't have outstanding depth charactorists. It doesn't employ Tesoros "Hot" technology and it's coil size but it does work very well in trashy areas, both in nails and alum. In fact nail/coin tests I have conducted with it and against other detectors I have or had as well as getting some of my detecting friends do the tests, the Compadre does better than the other detectors on the tests.
You could send your detector to Mr Bill and have him put a connector so that you could attach Umax coils to it, some have done the mod themselves.

[simonbaker]

The 2 pots at the bottom, one is for tuning the discrimination and the other is for ground balance. I'm thinking you may could tell which of the 2 are the disc setting by seeing if the wires go to the knob control. I had a gentleman tell me that the disc pot could be altered and you would affect the high range and the low range, in fact he had altered it so that the high range would knock out the dime/ penny, that way he could cherry pick quarters. If you adjust them, make sure you mark them first and use a screwdriver recommended for adjusting pots and don't touch the components on the circuit board. I did ask him how one would adjust the GB but he didn't have the instructions to do that. Oh yeah, the Compadre has the 180 disc, not 120. If you turn the disc all the way down, it will give a strong signal on nails.
There are 2 reasons why the Compadre doesn't have outstanding depth charactorists. It doesn't employ Tesoros "Hot" technology and it's coil size but it does work very well in trashy areas, both in nails and alum. In fact nail/coin tests I have conducted with it and against other detectors I have or had as well as getting some of my detecting friends do the tests, the Compadre does better than the other detectors on the tests.
You could send your detector to Mr Bill and have him put a connector so that you could attach Umax coils to it, some have done the mod themselves.

Thanks for that extra info. From my experiments, I'm guessing the pot #2 (lower left) is Ground Balance since it had an immediate effect on chatter when the coil is near the ground. With my sensitivity (pot #1) cranked counterclockwise, I find I need to crank the Ground Balance (pot #2) almost fully clockwise. Not much headroom if more GB is needed.

Also from my experiments I did have the impression that pot #3 was affecting the discrimination ranges. That one I put back to a middle setting and I'm content with how the discrimination knob scale corresponds to some air tested targets as noted previously.

This configuration feels like it makes a deeper, more sensitive detector, but I'd need to test on some marginal ground targets to confirm that.

BTW:

- What is the proper screwdriver for trim pots? I know if you're tuning with a scope you might want plastic wands to avoid effects. Since I'm tuning "blind", I'm just using a small metal screwdriver. Trying not to touch the circuit, but in the field....

- I'd be interested in what differences people find with the larger coils, anyone do some tests?

Thanks,

-SB

[kt315]

I see good photo of Compadre PCB I must inform you of. we have what we have... only some tiny steps give us some movement forward. yep we still have not a people who can give hight definition photos but we must not cry on this!

http://www.findmall.com/read.php?22,...409#msg-875409

I believe Compadre PCB will be #1 in your List

[simonbaker]

I see good photo of Compadre PCB I must inform you of. we have what we have... only some tiny steps give us some movement forward. yep we still have not a people who can give hight definition photos but we must not cry on this!

http://www.findmall.com/read.php?22,...409#msg-875409

I believe Compadre PCB will be #1 in your List

Very interesting, glad other people interested. Maybe I'll should go into tripod business, too many camera owners need one!

I have enjoyed my Compadre for many months. Soon I may have courage to cut the cable and measure the coil, then try some homemade coils. It is my only detector so I am shy to do it.

I would like to make schematic of it and compare to TGSL some time. I expect differences in discrimination circuit because Compadre has "180 deg" discrimination - no switch for all metal, just turn discrim knob to minimum.

Most dirt here is hard-packed clay very mineralized. I think I never find coin below 3 inches (7.6 cm). Very hard to dig anyway. I find objects deeper in wood chips, maybe 5 to 6 inches (12.7 to 15.3 cm). So I want more depth.

Has anyone tried this: Drill holes in box faceplate for tuning wand to adjust ground balance, sensitivity in field. Use rubber plugs for holes.

Regards,

-SB

[Eugene52]

Compadre Schematics

Happy New Year SimonBaker . Did you look closely at that comparison Chart ?? The Tesoro Lobo Results ?? The Tesoro Lobo has amazing results on everything , NO-EXCEPTIONS , I think alot of people on this forum just do not know how "Hot" that machine is !!! Besides forum members Maxbiri and a few others , the Lobo is very over-looked . This is a new year 2009 , hopefully we will finish some un-finished projects , like the Lobo and the Relic Hawk..............Regards..........Eugene52

[simonbaker]

Happy New Year SimonBaker . Did you look closely at that comparison Chart ?? The Tesoro Lobo Results ?? The Tesoro Lobo has amazing results on everything , NO-EXCEPTIONS , I think alot of people on this forum just do not know how "Hot" that machine is !!! Besides forum members Maxbiri and a few others , the Lobo is very over-looked . This is a new year 2009 , hopefully we will finish some un-finished projects , like the Lobo and the Relic Hawk..............Regards..........Eugene52

Lobo has alway been on my wishlist - heavy box though.

I am very curious why it performs so well and want to build it. Finishing un-finished projects definitely my goal too!

Regards,

-SB

[bklein]

Hi guys,
I recently bought a used Compadre. I was amazed really at its detection abilities compared to other generic detectors I have had. But it had a problem in that it beeped at the ends of abrupt sweeps. This was not due to the cable moving in the detection area. I could just lightly bump the coil with the palm of my hand and it would sound. So I sent the unit in to Tesoro. I got it back with a note saying the battery was bad and to install a new one and that they found the sensitivity was too high. ARrrgh. With a new battery it constantly beeped at the no disc. setting and was not as sensitive as original. And it still was sensitive to mild shock. I called them and was told that the coil was likely the culprit and that they had a better one they could offer. As the beeping at no disc. is not normal and was not there before I sent the unit back to them and am awaiting their call, hoping they find something this time. Any of you experience this sensitivity to mild shock? Anyone ever take the coil apart - I wonder what could be moving in there. I found that if I just slightly rotate the cable coming into the coil (black connector housing slid back) it would sound. So maybe a bad connection there. But how to fix? I'm hoping they fix it this time but if not I'd like to give it a go myself and am open to suggestions. They do actually kind of discuss this behavior in the manual. But I have never experienced this with other detectors and think it abnormally sensitive to it on this one.

[Qiaozhi]

Hi guys,
I recently bought a used Compadre. I was amazed really at its detection abilities compared to other generic detectors I have had. But it had a problem in that it beeped at the ends of abrupt sweeps. This was not due to the cable moving in the detection area. I could just lightly bump the coil with the palm of my hand and it would sound. So I sent the unit in to Tesoro. I got it back with a note saying the battery was bad and to install a new one and that they found the sensitivity was too high. ARrrgh. With a new battery it constantly beeped at the no disc. setting and was not as sensitive as original. And it still was sensitive to mild shock. I called them and was told that the coil was likely the culprit and that they had a better one they could offer. As the beeping at no disc. is not normal and was not there before I sent the unit back to them and am awaiting their call, hoping they find something this time. Any of you experience this sensitivity to mild shock? Anyone ever take the coil apart - I wonder what could be moving in there. I found that if I just slightly rotate the cable coming into the coil (black connector housing slid back) it would sound. So maybe a bad connection there. But how to fix? I'm hoping they fix it this time but if not I'd like to give it a go myself and am open to suggestions. They do actually kind of discuss this behavior in the manual. But I have never experienced this with other detectors and think it abnormally sensitive to it on this one.

The easiest way to isolate the fault would be to try it with another coil. You could take it to your local metal detector shop for testing. They should be happy to assist you, especially if they think you might purchase a coil from them.

[bklein]

I know there seems to be a problem with the connection but that alone may not be enough to explain the behavior. The coil is unique to this detector and local dealers do not stock this model or coil. And if it is the coil I would just have to buy another - like Tesoro suggests. I am more interested to know what in the coil could cause this and how to fix it. Does the lower cover slip off with force and then make the insides accessible or is everything covered in epoxy or some goop?

[simonbaker]

I know there seems to be a problem with the connection but that alone may not be enough to explain the behavior. The coil is unique to this detector and local dealers do not stock this model or coil. And if it is the coil I would just have to buy another - like Tesoro suggests. I am more interested to know what in the coil could cause this and how to fix it. Does the lower cover slip off with force and then make the insides accessible or is everything covered in epoxy or some goop?

What model Compadre do you have, the older one with 7" coil, or newer one with 5.75" coil? (I saw some ad for a "new" one with 8" coil, but not sure it's real).

-SB

[bklein]

Mine has the 7" coil.
Just got it back from Tesoro today in fact. They said they set the sensitivity back higher. Could be - I'll test it tomorrow. Looks like they may have even just put a new coil on it! It still will beep if I bump the coil. Is this common? I understand how the cable can be microphonic and cause this but I don't think that is what is happening....

[simonbaker]

Mine has the 7" coil.
Just got it back from Tesoro today in fact. They said they set the sensitivity back higher. Could be - I'll test it tomorrow. Looks like they may have even just put a new coil on it! It still will beep if I bump the coil. Is this common? I understand how the cable can be microphonic and cause this but I don't think that is what is happening....

It depends on how hard the "bump" is. My newer Compadre (with 5.75" non-removable coil") doesn't beep with casual bumps. But it is not a very deep detector also.

I would be glad to have beeps when bumped if it meant more depth and sensitivity. Can you do some air tests with common coins for us?

Still, if it beeps at the very slightest bump, that seems unusual. If it beeps just by sweeping in the air fast, I would say there is something not right.

I would think having Tesoro look at it is about as good as it gets -- not sure anyone here can help more. Of course if you are a tinkerer at heart and don't mind sacrificing the machine, you could start opening things and checking with oscilloscope, etc.

Is the cable really secure against movement? If not, tape it down and check again.

Regards,

-SB

[bklein]

I'd say it picks up:
Penny 6 1/2"
dime 5 3/4"
quarter 7"

But... it beeps at a repetitive rate once it gets a hit or gets hit.
I opened the circuit board area up and just moving the coil wires a tiny bit
makes it sound. But it may be reacting to all the metal where I am.
I have a scope etc. and I think I'll try my way through the schematic to see if I can pin this down. Pretty weird that Tesoro thinks it is fine.
Maybe they use headphones and I'm not....
Maybe they use a different power source....
That is one thing. Originally I had a low battery and didn't know it.
Now with a new one it comes on with a real long beeeeeeeeeeep.
Annoying for sure. Didn't know that the beep at the beginning is a battery indicator.

[simonbaker]

I'd say it picks up:
Penny 6 1/2"
dime 5 3/4"
quarter 7"

But... it beeps at a repetitive rate once it gets a hit or gets hit.
I opened the circuit board area up and just moving the coil wires a tiny bit
makes it sound. But it may be reacting to all the metal where I am.
I have a scope etc. and I think I'll try my way through the schematic to see if I can pin this down. Pretty weird that Tesoro thinks it is fine.
Maybe they use headphones and I'm not....
Maybe they use a different power source....
That is one thing. Originally I had a low battery and didn't know it.
Now with a new one it comes on with a real long beeeeeeeeeeep.
Annoying for sure. Didn't know that the beep at the beginning is a battery indicator.

I tend to agree with you that it doesn't seem quite right. Repetitive beeps are definitely not normal.

I have found with TGSL circuit (probably similar to Compadre) that sometimes while playing with the circuit, I get a situation where the speaker (or headphone) beep seems to cause a dip in the rail voltages which appears in the outputs of some op amps, and causing repetitive beeps. I'm not sure what sets that up exactly -- but you could check your V+, V--, and ground traces (rails) to see if that happens. Then make sure the voltage regulator chip is good; consider adding extra power supply filter capacitors or replacing the originals.

I find it very hard to diagnose exactly what causes these problems - often the signals look fine on the oscilloscope. But it is still worth checking the phases of the signals feeding into the Synchronous Detector to make sure they look right and that the discrimination knob moves the phase of it's driver signal appropriately. This could be tricky to know without having an additional perfect Compadre to compare with and excellent familiarity with the circuit.

Do you have a schematic for your model?

Touching wires with fingers could trigger beep for many reasons. Try jiggling them with a long wood stick instead.

At least your battery check is working fine and dandy!

Regards,

-SB