3900DiProPlus

[Luc]

Hello,
I try schematic white's of scotland "3900 di pro +" in order to add GEB control.
Thanks.

[kt315]

Re: 3900DiProPlus

what differencies are 3900, 4900, 5900 and 6000 schematics of?

imho, as TM-808 is TR DISC mode of 5900 and 6000, one can add the part to Classic I-III, Tesoro etc. schematics and get the powerfull mashine.

[Luc]

Re: 3900DiProPlus

I have watched fastly inner: 2 CA3140, 1 CD4053, 1 LM324, 1 LM393; LM393 could give marks them x/y (GEB/DISC) to 2 switch in the 4053; a CA3140 sure integrator (like TM80; LM324 differentiates them? ... I take apart the metal and to have the complete schematic to modify the GEB.
Bye.
Luc.
web translation.

[KT315]

Re: 3900DiProPlus




very similar to TR DISC of 6000 or/and TM-808. good schematic may be for DIY project. I think you could be take due to GEB of TM-808....

have nice day

[pelanj]

DI PRO Plus G.E.B. and discrimination of iron

Hello, I got this detector as a cheap deal and so far my feelings are mixed. I like the construction and how it sounds - however there is one big problem with it - Today I tried it a while on a beach. First I set the discrimination to eliminate small rusty pieces - but that definitely screws the ground balance and threshold is going down while the coil is going down. I was pushing the trigger with the coil at waist height to prevent false signals when lifting the coil from ground. I scanned a quite large part of a beach. Then, on my way back, I tried to groundbalance the detector correctly. In less than 20 minutes I have found some 4 coins, some bottlecaps and a small ring - going back in my own footsteps!

Is there a way to separate discrimination and ground balance with this circuit? With sensitivity at max the depth is quite nice.

Second, I would like to make a DIY DD coil for it - how (wire gauge, no. of turns)? I know the operating frequency and I can probably measure the two coils I have - 8" standard and 15" Blue Max monster. Thanks for any input on this topic

[pelanj]

I can buy a 2D coil from a Viking VK30 detector - which should be around 7,2 kHz - which is quite close to 6,59 kHz of my Whites. Would the coil work?

[pelanj]

Being a little wiser now, that coil would not work. And there is no easy way of adding a separate GB circuit - which is not necesarily a bad thing.