Compadre Schematics

[simonbaker]

I opened up my new Compadre (with 5.75" coil) control box to see if I could tune it "hotter", that is, more depth at the risk of more noise.

I only saw three small trim pots. They only turned one or two turns at the most. They were each set somewhere in the middle of their range. I turned each one max clockwise and then max counterclockwise.

I did not see any real difference in depth with my indoors air tests. I detect american coins at about 5 inches (12.7 cm) max; pennies, dimes, and quarters (clad) all register about the same depth, the dime a little less.

When I turned each pot to its max and min value, never did the detector go unstable or chirp or anything -- it just remained silent.

I'm pretty disappointed in the depth. I don't expect fancy features for such a low cost detector, but I was still hoping it could get a little more depth in all metal mode; I was really hoping there would be a pot that could make it more sensitive, but the trimmers don't seem to change much.

Has anyone (Steve in MS?) done any tests on the latest Compadre and found a way to tune it more sensitive (without modifications)? If so, what did you find?

BTW: at least the descriminator does work pretty well anyway in air.

[simonbaker]

Hi,
you had to dig it... ok here is the link :

https://www.geotech1.com/thuntings/showthread.php?t=12738

Sure the stuff is valid for bandidoII but with little variations (you can compare schematics easy I think) the same you can apply to all old tesoro's VLFs that are pretty similar MDs.

If there are problems understanding let me know... I will try to explain.

Kind regards,
Max

Thanks Max, you're a gem!
-SB

[Max]

Hi Max, what do you mean by the "Tesoro section", I'm not seeing that

-SB

Hi,
you had to dig it... ok here is the link :

https://www.geotech1.com/thuntings/showthread.php?t=12738

Sure the stuff is valid for bandidoII but with little variations (you can compare schematics easy I think) the same you can apply to all old tesoro's VLFs that are pretty similar MDs.

If there are problems understanding let me know... I will try to explain.

Kind regards,
Max

[simonbaker]

Hi,
Look at the Tesoro's section you'll find a thread about bandidoII where I explained (months ago) the various blocks etc

Kind regards,
Max

Hi Max, what do you mean by the "Tesoro section", I'm not seeing that

-SB

[Max]

Max:

Which is the more sophisticated or capable detector: the Bandido II or the Compadre (newest)?

Hi,
between the two bandidoII is sure a winner... at least the one I have made that can do impossible stuff I think for an original one, it's heavy modded with custom components to get the best... stability, sensitivity and good (not perfect) disc. But I think also original bandidoII will beat compadre hands down.

I'm sure Compadre simply cannot compete with bandidoII on stability... cause of components: they are truly lower noise in bandidoII... don't know if newer/last versions of compadre has them too or similar stuff, but I think not cause price is always less.

Also, bandidoII has many operation modes and setting... compadre hasn't, cause it's an essential MD... good but not as good as others from same brand.

So I think bandidoII is winner cause guys at Tesoro want this way and used finest solutions and options on it.

Kind regards,
Max

[simonbaker]

Hi,
I don't know about warranty (lifetime !) lost if screws are removed... ops... so consider well the pros and cons before screwing it...

4016 are integrated transmission gates (bilateral switches) much like fets operate; you can replace with 4066 if you need.

When disabled you have hi-impedance between port's leads... when enabled you got something from 50-200 ohm depending on device/brand/family.

I'm not sure... but think original Compadre has real fets there and you have to replace with transmission gates.

The TLC2262 is a modification too I think: they are present in bandidoII and the scope is wasting less power on op. amps. though getting very good noise level (lower than with LF ic).

Look at the Tesoro's section you'll find a thread about bandidoII where I explained (months ago) the various blocks etc

Kind regards,
Max

Max:

Which is the more sophisticated or capable detector: the Bandido II or the Compadre (newest)?

[simonbaker]

Hi,
are the two 0.47uF caps that make it motion... you can change them to something different but the more the cap the more the time it takes to retune. You can try using bigger using some double-switch to see what happens.

Kind regards,
Max

Thanks, it would be interesting to experiment with that for pinpointing.

[Max]

I don't know the circuit well enough yet, but I wonder if the motion mode depends basically on some kind of time constant somewhere (capacitor, etc.). Rather than make it totally static, maybe could switch to a really long time constant (like adding a capacitor in parallel with a switch) that would approximate a static mode for 10 to 20 seconds or so. Seems like that might be easier and avoid instabilities and drift problems. Just a wild idea.

Hi,
are the two 0.47uF caps that make it motion... you can change them to something different but the more the cap the more the time it takes to retune. You can try using bigger using some double-switch to see what happens.

Kind regards,
Max

[simonbaker]

Just take the screws out, if you have knowledge about dealing with electronics, it is no problem to do.

What I wish for is a way to add a static mode to the Compadre for pinpointing and sizing a target, it would then be a killer in trash for relic hunting. It does well for parks and such however.

I don't know the circuit well enough yet, but I wonder if the motion mode depends basically on some kind of time constant somewhere (capacitor, etc.). Rather than make it totally static, maybe could switch to a really long time constant (like adding a capacitor in parallel with a switch) that would approximate a static mode for 10 to 20 seconds or so. Seems like that might be easier and avoid instabilities and drift problems. Just a wild idea.

[Max]

Thanks Max and Steve for the answers.

- Any advice on opening the case to avoid any warranty problems, or does it open up very easy?

- By the way, are those 4016 parts with the red crosses out Bilateral Switches? Are the crossed out parts E-MOSFETs? Does this mean to replace the E-MOSFETs with Bilateral Switches? Is this a correction, or a modification?

- Can anyone translate the labeling to English or describe what each stage does? I'm just beginning to learn these circuits.

Many thanks,

-SB

Hi,
I don't know about warranty (lifetime !) lost if screws are removed... ops... so consider well the pros and cons before screwing it...

4016 are integrated transmission gates (bilateral switches) much like fets operate; you can replace with 4066 if you need.

When disabled you have hi-impedance between port's leads... when enabled you got something from 50-200 ohm depending on device/brand/family.

I'm not sure... but think original Compadre has real fets there and you have to replace with transmission gates.

The TLC2262 is a modification too I think: they are present in bandidoII and the scope is wasting less power on op. amps. though getting very good noise level (lower than with LF ic).

Look at the Tesoro's section you'll find a thread about bandidoII where I explained (months ago) the various blocks etc

Kind regards,
Max

[Steve in MS]

Just take the screws out, if you have knowledge about dealing with electronics, it is no problem to do.

What I wish for is a way to add a static mode to the Compadre for pinpointing and sizing a target, it would then be a killer in trash for relic hunting. It does well for parks and such however.

[simonbaker]

Thanks Max and Steve for the answers.

- Any advice on opening the case to avoid any warranty problems, or does it open up very easy?

- By the way, are those 4016 parts with the red crosses out Bilateral Switches? Are the crossed out parts E-MOSFETs? Does this mean to replace the E-MOSFETs with Bilateral Switches? Is this a correction, or a modification?

- Can anyone translate the labeling to English or describe what each stage does? I'm just beginning to learn these circuits.

Many thanks,

-SB

[Steve in MS]

Is that the "VR4" trimmer pot shown mentioned above? Did you just open the case and adjust it yourself? Or did you mount a new pot on the case?

When adjusting sensitivity, what test procedure did you use to decide on the best setting?

Thanks,
SB

Just advance the pot setting for more sensitivity so that it is still not too noisy. I have the newer Compadre, it is the pot at the top of the CB if I remember correctly.

[Max]

Ok, I'll melt down some nickels .

- Do you think it would be possible to use an audio transformer to boost the coil voltage somehow instead of new power supply?

Hi,
impedance matching ? Yes is possible, but sure it's not the best way to gain depth. Driving the transformer will lead you to other problems cause you will need more current to energize the magnetic core otherwise your colpitts oscillator at tx will simply die cause of too hi current required... and if you use e.g. ferrite core you'll probably have problems with magnetic hysteresys too: to do this , then, you must redesign the TX stage and maybe use a different approach than the colpitts used by guys at Tesoro.

A good impedance matching can maybe give enough field gain to have a good increase in performances but I think this is really overcomplicated to achieve just using a ready made audio transformer... much like a CaptainCrunch's (*) adventure... I will not advise you do so: better trying with power supply mod... easier than modifing the oscillator. Similar stuff I do, usually, when under irish wiskey... the oscillator mods I mean.

You can, for example, buy a prebuilt switchmode power supply module to get the 24V from lower voltage batteries and then try to mod the unit... or you can also build yourself if have required skills. Some simple SMPS really easy are made around the old IC 78s40 controller... really easy stuff... an inductor... and few spare components and you'll get 24V from e.g. 9V or 12V and with enough current to power more than a single compadre.

Kind regards,
Max

(*) for those who ignore who is CaptainCrunch... he is (not a superhero ? well... yes he was/is! really a pioneer of that stuff...) the phoneline hacker/phreaker that fooled AT&T using the whistle he found in a box of Cap'nCrunch cereals... dialing to the world for a bunch of dollars...

[simonbaker]

Hi Esteban,

red switch? What func?
value for red rezistor?

(tesoro compadre schematic)

Thanx

Michal

Sorry my english....

Yes, Esteban, can you explain what the red switch does and what the value for the red resistor is?

- Also, is the "slim-line coil connector" for interchanging coils?

- Do you know what coils are compatible with the new Compadres, or what mods would be necessary to change coils?

Thanks much
-SB