IDX-PRO+VDI

[medj]

Finally back on it's a minefield
Because it reveals only iron and strongly after a long experience with him
It has doubts in my words
Or has some way to turn it into gold detector
Leave me a message

[Koala]

"My audio is loud and hurts when on full on vol slider." lucky you

Mine very very quite in PP mode. Not driving the speakers hard enough. Double checked triple checked everything. Can't find my fault. I appear to be not the only one that had this fault. Not so lucky.

In Disc mode is not bad.
Disc and PP are nearly identical depth except you would walk passed in PP mode due to the faint volume.

Everything else is perfect. Rock steady and stable.

just seen you reply"your chosen darlington and it has only 1/2 of the gain of the designed part" must have miss read the data sheet that will be my problem then. THANKS

[golfnut]

I read the datasheet for your chosen darlington and it has only 1/2 of the gain of the designed part.

S

[golfnut]

My audio is loud and hurts when on full on vol slider.

i never tried depth tests with different phones - didnt think that phones would have influence much.



S

[Koala]

Been out to get some low impedance earbuds could only fine one pair that were marked and there were 16 ohms. Got some old phone earbuds to test with as well. These are the easy detect distances. All in PP mode All had an extra inch or so very faint
1.2M ohms 5 1/4" possibly piezo
32.2 ohms 8 1/4"
16.8 ohms 10 1/2
Looks like I need more volume anyone know how I do this.

ashefr1 one diferance between indoor testing and outdoor is the ground I would suspect a problem with the shielding of the coil.

[ashefr10]

Hello, mine with a DD disk really works indoors but once outside, I found that the audio level is not terrible and he starts fluctuated without any reason then only indoors stuff nothing

[Aiko]

I also have the latest modded version of Eduardo. It is not my solder job, but it looks neat, so I will test both versions (the latest of Eduardo and my from the silverdog PCB) and I will share the results.

[Koala]

Aiko

I have read all of the md4u.ru long thread and only found one mention of the same thing as in post 1526 above unfortunately the fix is lost in the translation. Found three mentions of poor audio on here tried one fix by reducing a resister value I have tried it and it made things worse. One was caused by using a 4 ohm speaker causing a transistor to burn out. Found a mention that the volume is okay with a piezo. I am using 30 ohm speaker and headphones going to buy some cheap 16 ohm earbuds this afternoon and see if that helps. I have reversed d3 and changed for a zener 2.7 this has made pinpoint mode better and Disc worse this may or may not be true as the board is not mounted I have found that even though the search coil is not moved and the shaft marked with the distance when you retest you can get a slight difference in distance when retesting. Overall this project is working brilliantly and exceeds my expectations.

[seadoggy]

What LCD can i use for VDI??pls give link guys!

[Aiko]

Aiko
Have you tried on headphones. I have poor range in all metal mode on speaker but found the audio was there but very week and stronger sound in disc mode. Not fixed yet.

No, I did not tried yet on headphones. Probably you are right and the depth is the same, but the audio level is poor. The threshold pot. is working perfect in all metal mode. It is a nice working project.

[Koala]

Aiko
Have you tried on headphones. I have poor range in all metal mode on speaker but found the audio was there but very week and stronger sound in disc mode. Not fixed yet.

[Aiko]

This is my IDX-PRO made with the silverdog PCB. Everything is working fine right from the start. The only problem that I can find is that the pinpoint (all metal) mode is less sensitive then the discrimination mode. As example if I can detect 1 euro coin
at 35 cm in discrimination, in all metal the detection is only 25 cm. The coil is DD shielded with aluminum foil.

[gtdavid]

What page is the 3 tones mod I did not see that one..
I could only get the pcb and a few components from silverdogs the other components I have to order from a different source ..
I may add the vdi at a later date , just going with tones atm.

[golfnut]

I think the parts supplied in the kit work ok.


I cant see the advantage litening to 2 tones (Iron and non Iron) - I would like three tones for non ferrous.

Silverdog mentioned he found the vdi a little confusing in use - all of those numbers flashing around - plus the vdi only works on larger amplitude signals.



The scheme on the XP detectors is good

S

[gtdavid]

Ok guys
I am just doing my final parts order for my idx and I was just wondering if you had any suggestion for better parts ie better alternative ic's ect.
I have ordered the fisher cz coil also what capacitors should I get for tuning that one..
Also do you recomend the 2 tone mod or any other mods..
Thanks
David