Just finished adding Ground balance to my Cibola

[Sven]

End results were excellent. Using 9x8" coil, now Air tests about 1 1/2 - 4" deeper than fixed groundbalance in all metal. Gained 1- 3" in disc. mode.
Meets or exceeds the air test results I got with the Tejon I owned.

Hot little booger with the 5 3/4" coil, too.

I am happy with the results using the 10 turn pot for GB.

When my back gets better, going to take it for a test run.

Here's some pix

 

[saginawian]

Thats sweet! Just wondering if you would you give some explanation to the pictures - did you basically just solder a GB control on? Where did you get the parts to do this? This might be a fun winter project to work on.


thanks, Ian

 

[Sven]

Thats sweet! Just wondering if you would you give some explanation to the pictures - did you basically just solder a GB control on? Where did you get the parts to do this? This might be a fun winter project to work on.


thanks, Ian

I will work up a how to and parts used in a few days. Basically its removing the internal fixed pot and replacing it with a 10 turn that gets mounted on the faceplate where the pinpoint button was. The wires from the pinpoint button were soldered to a On/off toggle switch that was mounted below the box on the armrest rod.

Just a reminder, doing any mods to your Tesoro voids the warranty. So if you screw up, it's going to cost you.......

 

[lurksalot]

n/t

 

[Old California]

Hello Sven,

Great idea adding on a GB Pot Depending on ground condition they are necessary.

I was looking at the removed miniature pot area from your pictures and noticed you only soldered in two wires coming from the circuit board leading to the 3-pin 10-turn pot, Shouldn't there be three wires coming from the pot and soldered in the marked yellow X areas as from the attached pic? Otherwise, It won't ground balance?

Maybe I'm not seeing it correctly?

HH, Paul

 

[Old California]

Now I see the third wire soldered on the board, I would have soldered the three leads on the same areas the miniature pot was removed from.

Good luck have fun and try her out in the back yard making sure it properly ground balances.

HH, Paul

 

[Sven]

Hello Sven,

Great idea adding on a GB Pot Depending on ground condition they are necessary.

I was looking at the removed miniature pot area from your pictures and noticed you only soldered in two wires coming from the circuit board leading to the 3-pin 10-turn pot, Shouldn't there be three wires coming from the pot and soldered in the marked yellow X areas as from the attached pic? Otherwise, It won't ground balance?

Maybe I'm not seeing it correctly?

HH, Paul

You only use #2 and #3 pins. #1 pin of the orig. pot was soldered to the board but to a dummy which went nowhere. I am also assuming the V uses the same(?) board, different chip(?) and the adjustable GB pot on the faceplate was soldered to the two holes which I used on the Cibola.

 

[rentasquid]

Why, when you can have a Vaquero? Are you an electrical guy that just likes to tinker?
Nice job on the mod, nonetheless!

J.

 

[Sven]

Why, when you can have a Vaquero? Are you an electrical guy that just likes to tinker?
Nice job on the mod, nonetheless!

J.

I like to tinker and it only cost me about $20.00 to do the mod. Lot cheaper than a V.
Instead of using a 3 3/4 turn pot, my Cibola has a 10 turn pot. You can GB more precisely than the V.
From what I understand the Cibola runs hotter and smoother than a V after the mod is done.
Something to do with the different chips used in the V & C.
Another difference is the Disc/ all metal switch on the V. It's a pain if you like thumbing the disc. mode
and then want to change into all metal to hunt. You loose the Disc. setting if you change into all metal.
With the toggle switch under the rod, I can instantly switch back and forth from disc to all metal mode.

The pinpoint button was removed as it's not really needed to pinpoint.

I can now see why you need to send the C to Tesoro to re-calibrate the internal factory fixed GB pot when switching from the 8x9 coil to the 5.75 coil..............

 

[tvr]

Great job! I have been procrastinating on opening my Cibola and investigating how to do this mod ... After just reading this forum for several months ... you have inspired me to register. Is the potentiometer the same value as the trimmer on the board? I was thinking about selecting a toggle switch that is open at center position, momentary contact (pin-point) pulled up and locked contact (all metal) pushed forward.

 

[Sven]

Great job! I have been procrastinating on opening my Cibola and investigating how to do this mod ... After just reading this forum for several months ... you have inspired me to register. Is the potentiometer the same value as the trimmer on the board? I was thinking about selecting a toggle switch that is open at center position, momentary contact (pin-point) pulled up and locked contact (all metal) pushed forward.

You can add any type of toggle you like. It pinpoints really well without needing a momentary contact for all metal. If it had a slower retune speed it would be worth having.

Bourns 50k ohm pot MFG#3540S-1-503L
Mouser Electronics

 

[tvr]

Sven,
Thanks for the part number!

Yes Cibola pin points real well without using pin point. I like the pin point for depth information and to trace and size things without thumbing the discriminator down to the stop on iffy beeping stuff. On sandy and wood chipped play areas, I'd like to lock it in for all metal ... right now I hold the button down. I need to do the mod. I also have a Tejon. Tejon seems to be deeper on most targets in the ground but re-tunes even faster than Cibola.
Thanks again!

 

[Old California]

Thanks Sven,


Great job with your GB mod and really I appreciate you taking the time posting your GB mod and answering our questions, Every bit of information on these type of GB improvements greatly helps those performing a GB mod when they decide to tackle one themselves.....I've done several GB mods on other types of detectors and always looking for tips and fresh ideas, So I relish any information from those who post theirs.

I do have a question regarding both your pictures of the circuit board, one board with the GB trimmer pot and the other circuit board without the trimmer pot. The circuit board with the GB trimmer pot removed has a third wire soldered into the circuit board and the circuit board with the trimmer pot doesn't have this wire? Is this added wire going to the GB pot that you've added on?

Thanks again, Appreciate your time, zest and enthusiasm.
Paul (Ca)

 

[Sven]

Thanks Sven,


Great job with your GB mod and really I appreciate you taking the time posting your GB mod and answering our questions, Every bit of information on these type of GB improvements greatly helps those performing a GB mod when they decide to tackle one themselves.....I've done several GB mods on other types of detectors and always looking for tips and fresh ideas, So I relish any information from those who post theirs.

I do have a question regarding both your pictures of the circuit board, one board with the GB trimmer pot and the other circuit board without the trimmer pot. The circuit board with the GB trimmer pot removed has a third wire soldered into the circuit board and the circuit board with the trimmer pot doesn't have this wire? Is this added wire going to the GB pot that you've added on?

Thanks again, Appreciate your time, zest and enthusiasm.
Paul (Ca)

I see what you mean now. What you are seeing is an optical illusion. The wire in question is green in color and it was positioned out of the way to show the board. I am using a new camera and apparently the aperture did not focus on that wire at the angle the picture was taken. So the green wire blended in. That's the only explanation I can think of. That particular green wire you are questioning about and yellow go to the pinpoint button. It shows up clearer in the picture below. These two wires were desoldered from the pinpoint button.

 

[tabdog]

I know a lot of people, including myself

are interested in this kind of information.

I just wanted to thank you for sharing it with us.

[size=x-large]A BIG THANKS[/size]

Tabdog

 

[Old California]

Thanks Sven,

For clarifying this other wire was not related with the GB mod but instead for the pin-point switch, Again you did an outstanding job with the GB mod.

Well done!
Paul (Ca)

 

[tvr]

Sven,
Parts are on order! Thanks for the motivation!
tvr

 

[Sven]

Sven,
Parts are on order! Thanks for the motivation!
tvr

When you take the knobs off the pots on the faceplate. take a magic marker of different colors and mark the pot ends. Then jot down on a pc. of paper what colored pots go to what control. Don't leave it to memory what pot goes where............

Have fun

 

[Jeff (or)]

Does the ground balance tie in with the all metal and disc, or just the all metal?

 

[Sven]

Does the ground balance tie in with the all metal and disc, or just the all metal?

Ties in with both. The unit comes with a factory set ground balance which is not perfect for all locations, so you loose depth. Now with manual GB you can adjust for any ground conditions including hot rocks.