IDX-PRO+VDI

[wallker]

Should this MD run on 8 or 9 volts?

Or even less, 4V, as shown on schematic???

[Koala]

original is powered by 12v

starts to fail when the unloaded pack measure around 9.5V

runs at +4 and -4 so needs 8 volts. But there is also a voltage drop on the protection diode

[wallker]

original is powered by 12v

starts to fail when the unloaded pack measure around 9.5V

runs at +4 and -4 so needs 8 volts. But there is also a voltage drop on the protection diode

Thanks for clarifying that Koala.

[dbanner]

Isn't the mcp602 setup on one side as inverting amplifier?

[dbanner]

Question, IDX Pro red board, With my Scope in XY, Channel 1 probe on X and Channel probe 2 on Y, GB goes up and down, would that not be 0, Should it not be at the -95 - +95 left to right ? by switching the probes it does switch the GB alone the 95 Plain. With a Nickel it is being detected in the negatives not the positive, look at the little sketch please and tell me what you think. Seems like everything is all bunched up together besides Nickels and ferrous metals. I do not know if it is they way I have my Oscope set up or if there is a problem with the detector, the scope is Plugged right in to the detector with out a MCP602

[ATTACH]45058[/ATTACH]

Isn't the mcp602 setup on one side as inverting amplifier?

[wallker]

yup. almost. just add Zener diode on outputs of the comparators.

typical mistake that you do not want fix and notice.

thx for heads up kt315.
Is this way ok?

[kt315]

this way

[wallker]

Thanks for confirmation.
I was just too lazy to draw correct symbol.

[wallker]

Just finished assembling the IDX smd board, that Koala posted.
Corrected PCB a bit, and it works.
I was too impatient and just wanted to see does it works, so i conected fast-wound 0.7 mm wire for tx coil and rx from IGSL.
Poor detection due to bad coil specs and off resonce, but still works.

[kt315]

whites 6.59kHz coil has a cap inside. you have to connect outer cap to tx winding, value in range 0.5-1.0uF.

[wallker]

IDX SMT Layout

Added R41, R46.
Corrected connection of C5, C6, R24 and VR3.
Bom may need to be updated.

[wallker]

whites 6.59kHz coil has a cap inside. you have to connect outer cap to tx winding, value in range 0.5-1.0uF.

Hi kt,
I did connected caps, my coil is open, still in bench mode, connected just for testing purposes.

[Koala]

if I was to build a new coil for my IDX I think I would be tempted to try an omiga style

Seem to be getting good results on the Russian metal detecting forums. Its alleged to have the same VDI and pinpointing accuracy as a concentric but punches through mineralized ground more like a DD.

https://www.google.co.uk/search?q=%D...ih=486#imgrc=_

[wallker]

Hi Koala, fo you have some parameters for omega coil?

I might give a try building it.

[Koala]

Hi Koala, fo you have some parameters for omega coil?

I might give a try building it.

Nope you would be the first to try

the inductance and capacitors would be the same as per first page of this thread.

RX is half the diameter of the TX


just don't know how to calculate the size of the squiggle so the RX is near the centre. Looks to me to be a fraction below RX size