IDX-PRO+VDI

[sinko1]

hi who is last pcb and shematic. thanks

[der_fisherman]

I have added some VDI boards to my shop £4 GBP each
I will add a kit for these very soon if you can't program your own PIC

IDX Pro boards will be available early next week, kits will be available as well

thanks to Eduardo and Holyuser for a great project


Holyuser, may we ask if you have considered an alternative to your VDI greeting ?,
"Holyuser VDI" or "Geotech VDI" maybe ?

Really good news from you and Holyuser....
regards
Andy
PS. I was only checking up yesterday as to whether kits etc. would be available or not!!! Got to get my IGSL finished first.

[holyuser]

Holyuser, may we ask if you have considered an alternative to your VDI greeting ?,
"Holyuser VDI" or "Geotech VDI" maybe ?

Will be done in the coming weekend.

[silverdog]

I have added some VDI boards to my shop £4 GBP each
I will add a kit for these very soon if you can't program your own PIC

IDX Pro boards will be available early next week, kits will be available as well

thanks to Eduardo and Holyuser for a great project


Holyuser, may we ask if you have considered an alternative to your VDI greeting ?,
"Holyuser VDI" or "Geotech VDI" maybe ?

[eduardo1979]

OK - thanks.
Do you have a schematic that matches the PCB layout?

I have not. There are very few modifications. The detector is almost like the original. I modified a bit sensitive stage. I canceled the frequency potentiometer. No major changes.

[Jerry]

More field testing on the IDX/VDI today at two different sites, on sandy and black soil. The IDX/VDI was fooled by steel bottlecaps and large metal pieces just like the TGSL. I guess this problem is inherent to VLF's, and I will have to live with it. At least with a large piece you can tell by the size of the target response. Battery life has been better than I thought, so far today Ive had it running with the VDI on for 5 hours, and its still running. Well at least all the mosquitos were gone today

Bottle caps are a way of life with DD coils. Not so much with a concentric. Finding bottle caps has more to do with coil than detector type.

Good to see reports of field testing.

Jerry

[Qiaozhi]

Yes.

OK - thanks.
Do you have a schematic that matches the PCB layout?

[eduardo1979]

The Freq. adj. was omitted on the Eduardo board. I think what he means is VR4.

Yes.

[eduardo1979]

inductances?

thanks

TX=0,587mH
RX=36,5mH

[Wiltran]

The Freq. adj. was omitted on the Eduardo board. I think what he means is VR4.

[Qiaozhi]

The P4 in the scheme is to adjust the frequency as long as there are 2 metal detectors looking for the same type very close to each other. PCB is the Threshold p4. I did not know what you mean, a PCB or electronic schematics.

I'm referring to this schematic ->

[Amalio]

TX=35 TURNS 0,70 +1uF PARALLEL CAPACITOR
RX=270 TURNS 0,18 +33nF PARALLEL CAPACITOR
FOR DD COIL 27CM.

inductances?

thanks

[eduardo1979]

Hi Eduardo,
can you please explain that sentence for me as I simply don't understand (too long in Germany!) exactly what you wanted to say, sorry.
regards
Andy

The two capacitors of 1uF both 33nf like go into the search coil and run parallel to the coils. The 1uF capacitor in parallel with the TX coil and 33nF capacitor in parallel with the coil RX.

[eduardo1979]

I think he means the 33nF capacitor is inside the search head, and not on the PCB. Therefore it is not shown on the schematic. If I'm wrong, then Eduardo can explain further.


Eduardo - The P4 potentiometer is labelled "Freq" on the schematic, and it appears to be fine tuning the frequency of the TX oscillator. How is this related to the Threshold? I don't understand.

The P4 in the scheme is to adjust the frequency as long as there are 2 metal detectors looking for the same type very close to each other. PCB is the Threshold p4. I did not know what you mean, a PCB or electronic schematics.

[Qiaozhi]

Hi Eduardo,
can you please explain that sentence for me as I simply don't understand (too long in Germany!) exactly what you wanted to say, sorry.
regards
Andy

I think he means the 33nF capacitor is inside the search head, and not on the PCB. Therefore it is not shown on the schematic. If I'm wrong, then Eduardo can explain further.

The P4 is the Threshold and this potenciometer is very necessary. This potenciometer must be put on the front panel of the metal detector. The Threshold influences the PIN-POINT and the detection in mineralized areas to eliminate false signals. The 1uF capacitor is not because the PCB is mounted inside the search coil with 33nF capacitor.

Eduardo - The P4 potentiometer is labelled "Freq" on the schematic, and it appears to be fine tuning the frequency of the TX oscillator. How is this related to the Threshold? I don't understand.