IDX-PRO+VDI

[Carl-NC]

Q1 & Q2 form a feedback oscillator circuit. The TX coil and I presume an internal capacitor set the oscillation frequency.

[orrtizz1]

Kind regards to everyone,
I am starting to assemble the IDX-PRO detector; however, several questions arise that I hope someone kind enough to overlook my ignorance can answer. I have seen several schematic diagrams, but how is the signal for powering the Tx coil generated? It is supposed that the Tx coil should be powered with a sinusoidal signal; however, within the schematic diagram, I don't see any type of generator already implicit in the design. Thank you very much to anyone who reads this and, of course, to anyone who has the patience to provide me with an answer.

[bonchev2]

Hii Mazixx. Thanks for your reply and yes you are right is not something new and I didn't say there was. For the coils is almost the same, RX is with little lower freq.So far all the parts are found but maybe LF347 is harder to find and can by replaced with TL074 or TL084 I try it LM324 but I don't like the result. Greethings, and Happy Holydays to everyone

[mazixx472]

https://youtube.com/@hobbytv_the_kin...YiuwI4SbIfxtlg

Resonance frequency 6590 Hz max
Capacitance 1uF min, 1.2 uF max (3 caps in parallel)
Inductance 540 uH nominal
Resistance 1.6 ohm max
RX tank circuit
Resonance freq. 4900 Hz max
Capacitance 30 nF min, 36 uF max (3 caps in parallel)
Inductance 36 mH nominal
Resistance 70 ohm min, 120 ohm max

I'm not writing that the board won't work, what I mean is that with one capacitor it will be difficult to obtain a given RX frequency of the coil, and by the way, you don't show anything new on your website except the board, connect the coil and show what the frequency is and what this cosmetic gives, In my opinion, it brings nothing new.
there is no need to be offended, just tell me that in order for it to work well, some elements need to be replaced with newer models, and so replace lf347, NE 5534, BC547.BC327,

[bonchev2]

https://youtube.com/@hobbytv_the_king_detectors?si=gbYiuwI4SbIfxtlg

[bonchev2]

If you don't like 33nf to be on the board just placed in searching coil, simple. That's doesn't mean that pcb will not work properly. You can see in my YouTube channel how it's work

[bonchev2]

I made this pcb and it working fine. Mazixx is funny what you saying

[mazixx472]

Yes, the board is 2-layer, but it has one minus, it won't work very well in IDX and that's because the 33nf capacitor in RX has no place for it, it has to be in the coil, my justification for tuning the coil is that one capacitor is not enough to obtain the desired frequency, this is just my opinion

[freeker007]

Is there a parts list?VDI,LCD

[Nightryder]

Who have this pcb layout can you share

I have not seen this PCB before. It looks to be 2-layers. If this is true, try searching with the keywords "2 layers" "2024". Perhaps PCBs manufacturers websites have it.

[paku]

Who have this pcb layout can you share

[Carl-NC]

The 950 is a concentric and they tend to be very immune to thermal shifts. But try another coil just to make sure.

[dgm]

Good evening Mr. Carl, on this metal Idx Pro I have always used an original blue max 950, and I have never tried to replace it with another coil, but I will try immediately. Thanks for his contributions, always welcome.

[Carl-NC]

dgm, post a pic of the coil. Have you tried another coil?

[pito]

Hello, the head calibration is probably slipping due to the heating of the epox. =epoxy resin is not necessarily the culprit, thermal expansion of the head.....
Check the head.
On a sunny day put it on the ground and make a shadow on it, a piece of cardboard 10 cm above the coil, turn on the machine and check the efficiency, remove the cardboard, wait 15 minutes and check again.