IDX-PRO+VDI

[scrungy_doolittle]

All fuse settings are included in .hex file.
Oscillator mode is INTIO2 (PIC16F88 ) or INTOSCIO (PIC16F690).
Reset is internally tied to Vdd, reset pin is an input.
The watch dog timer and brown out both are off.

I have one I got from Andy, have to add a display to it.
I would dearly love to port this to a different processor, and add some features to it. I want a timer so I can set it for say 45 min, and start hunting, and when it expires, have it let me know. That way I can run out and hunt during noon hour and not be back to work late.

Would it be possible to get the source? I'll be glad to share the source back when ported. I want to port it to a 8051 platform, as well as a PIC24 platform.

[Koala]

Can anybody give me a list of Voltage PIN Checks and Oscilloscope Tests - that I can do after work in 2 hours from now ?
I have limited time - so a list of things to do would be very helpful
- so I can list some info here ...

Thanks !

http://www.geotech1.com/forums/showt...658#post181658

[der_fisherman]

I don't see the Short - looks clean.

I do believe it was under the resist, you won't see it. Especially so that the board is built. You need someone, maybe Silverdog, to tell you exactly where it is. Someone else here could possibly confirm this? (Or deny it!!). You may need to tell him the version....
Also, I personally would never build a PCB and place the resistors so far from the PCB, they should be lying on it....its mechanically and electronically bad.
regards
Andy

[Gwil]

Cats like to watch people working. They never offer to help though.

[Silver Dollar]

I found this picture in the archives;

[ampirate]

Well results are as follows :

Coils:

TX: 35.6 mH , 1uf cap
- Sine Wave , between 16.25-17.5V p2p Wave height , 6.6KHz(150 us) ; (measured at 0.5v/seg , 50us/seg)

RX: 0.587mH , 30nf cap
- Sine Wave , 35mv p2p Wave height , 6.6KHz(150 us) ; (measured at 0.5v/seg , 50us / seg)

Chips : Pins:

- U1: Pin6: Sawtooth, 2V p2p , 6.6KHz(150 us) ; (measured at 1v/seg (0.1V x10) , 50us / seg)
- U5: Pin1: Sine, 2V p2p , 6.6KHz(150 us) ; (measured at 1v/seg (0.1V x10) , 50us / seg)
- U3: Pin7: Sine, 2V p2p , 6.6KHz(150 us) ; (measured at 1v/seg (0.1V x10) , 50us / seg)
- U5: Pin7: Sine, 2V p2p , 6.6KHz(150 us) ; (measured at 1v/seg (0.1V x10) , 50us / seg)
- U6: Pin1: Sine, 2V p2p , 6.6KHz(150 us) ; (measured at 1v/seg (0.1V x10) , 50us / seg)
the last 4 readings bounced up/down +/- 1V

I thought that I checked everything.
But, I still get NOTHING from the PIEZO.

[Koala]

Null too far out U1 Pin6: far too high to work properly. Needs to be around 200mv. I normally aim for 200mv and ends up about 250mv when cased and epoxied up

[der_fisherman]

I found this picture in the archives;
[ATTACH]31810[/ATTACH]

That is a good picture, well done for finding it, hopefully that is the problem he has, he can now fix it.
Also, the board shows properly soldered in resistors, laying on or close to the PCB, as they should be.
Regards
Andy

[der_fisherman]

Problems with your PCBs

Board snapshots :

Board 1:
[ATTACH]31785[/ATTACH]
[ATTACH]31786[/ATTACH]

Board 2:
[ATTACH]31787[/ATTACH]
[ATTACH]31788[/ATTACH]
[ATTACH]31789[/ATTACH]

Coils :
[ATTACH]31790[/ATTACH]

Other friend who dropped into my project:
[ATTACH]31791[/ATTACH]

I don't see the Short - looks clean.

As far as I can tell with the bad picture quality that I guess a mobile phone made, I could not see the short.
What I do see is appalling workmanship, leads on most components are far too long, which means that they could have tiny movements and cause major signal changes in such delicate circuitry......such long leads change capacitance dramatically...
My best advice to you is to simply start again, after reading some tutorials on how to place components on a PCB correctly and solder.
I would also suggest that you identify each resistor and capacitor using a meter, to make sure that you have the exact right component in the right places.....it is easy (we have all done it!) to place say a 4K7 resistor where a 47K0 needs to be placed. Caps are even easier to misplace.
All leaded components must be placed as close as possible to the board, but without straining the component to achieve this. I would say that you could probably stand up some of the resistors on one end, to allow all to be fitted in dense areas...though the other board shown is neat and looks good, did not seem to need this at all....
Most of your components can be saved by simply cutting them off at the PCB, removing the legs individuallyusing a solder iron (they sort of "stick" to the iron and are easily and quickly removed) and in the end, reforming the legs using a long nose pair of pliers, refitting and soldering. That way, you will not heat stress the PCB too much.
I could not see well how your soldering is though, that may also be questionable too....
There seems to be a socket with components stuck in it instead of chips, this looks terrible. If you need to do such mods (are they documented here?), then remove the socket and solder correctly.
To remove sockets, cut them up and remove each pin separately, do not try to remove it whole, or try to reuse it. Sockets are very cheap. Reusing will just cause extra problems.
Perhaps some quality pictures of your PCBs from both sides, using a better camera, might be a good idea if you want further help from us here.
As built, you will have major problems getting either them to work reliably if at all.....as the old joke says, "if you want to drive to London, don't start from here!"
Think of this as a learning curve.
By the way, there are many soldering tutorials on the web, you can copy a few and print them out for reference.
Best of luck.
regards
Andy

[silverdog]

That is a good picture, well done for finding it, hopefully that is the problem he has, he can now fix it.
Also, the board shows properly soldered in resistors, laying on or close to the PCB, as they should be.
Regards
Andy

There won't be a short on current boards - it happened once with a batch, they were soon dumped when it was identified

[Silver Dollar]

Well results are as follows :

Coils:

TX: 35.6 mH , 1uf cap
- Sine Wave , between 16.25-17.5V p2p Wave height , 6.6KHz(150 us) ; (measured at 0.5v/seg , 50us/seg)

RX: 0.587mH , 30nf cap
- Sine Wave , 35mv p2p Wave height , 6.6KHz(150 us) ; (measured at 0.5v/seg , 50us / seg)

Um Shouldn't the TX be 587uh?

[jlsilicon]

Sorry, yes :

TX: 0.587mH , 1uf cap
- Sine Wave , between 16.25-17.5V p2p Wave height , 6.6KHz(150 us) ; (measured at 0.5v/seg , 50us/seg)

RX: 35.6 mH , 30nf cap
- Sine Wave , 35mv p2p Wave height , 6.6KHz(150 us) ; (measured at 10mV/seg , 50us / seg)

Actually, I don't understand the problem with having the components raised with 0.25in leads, leaves moving and testing space.
On what I remember, 0.25in or 1in stretch should have no effect on a 6KHz signal or even 1MHz ...

Glad to hear from you Silverdog. The board looks fine - no short - I can see through the board fine there.
I meant problems with components mounted wrong, or needed Mods.

I have Built this Board 3 times now, with the only working Board accidentally using an Oscillator Can
- which I believe should not be used - and was replaced with a Piezo this week.
And, I now can Not bring this same Board up at all either.
NO Sound - like a dead Brick - like the other boards.

I spent yesterday lunch and last night time to get large Images and Pin Voltage and Oscilliscope Tests.
Under the hopes, that someone might provide assistance in spotting particular locations for the problem.
I am glad to get Images of the Pin Oscillation Tests - if anybody can direct me to where ...

Any assistance is appreciated,
Thanks !

[Koala]

TX looks to working fine. RX has too much volts to work properly. Have you a working coil to try. Null too far out

[jlsilicon]

I have been shifting the coils around, have not tried with Scope yet.
I just assumed that the Piezo should output SOMETHING of a CLICK or BEEP - while shifting the Coils, but not.

Will try tonight.

Thanks Koala.

[der_fisherman]

Problems-----

Actually, I don't understand the problem with having the components raised with 0.25in leads, leaves moving and testing space.
On what I remember, 0.25in or 1in stretch should have no effect on a 6KHz signal or even 1MHz ...

I meant problems with components mounted wrong, or needed Mods.

NO Sound - like a dead Brick - like the other boards.

Any assistance is appreciated,
Thanks !

I was trying to help you, my advice was valid and I will only post the truth. Many here will think the same as I do, but not say it. How does that help you further?

Think about it, it still doesn't work........and you know that your building method is OK.....then surely you can fix it....?

My personal opinion is that if you want stability in a metal detector, nothing should move except the speaker cone when you find something. Any variations in capacity in sensitive areas of the Rx circuit can cause unwanted sounds and effects.

Some here have had serious problems just when pot wires were flapping about when searching, they need to be short and plaited together for many designs....

But each to his own style.......

best of luck

Andy