SD2000 Front end

[JC1]

links

Here are some links on IntraFet low noise devices.

notice the different noise, capacitance and die sizes.

now to get lower noise than the lowest one here you

would need to start paralleling them.

http://www.interfet.com/pdf/P_NJ450L.pdf

http://www.interfet.com/pdf/P_NJ903L.pdf

[JC1]

3

this one looks like 3 in parallel,

in one package, very low noise,

very high capacitance, very large die.

http://www.interfet.com/pdf/P_NJ3600L.pdf

[Aziz]

this one looks like 3 in parallel,

in one package, very low noise,

very high capacitance, very large die.

http://www.interfet.com/pdf/P_NJ3600L.pdf

Thanks JC1,



so we can reduce the input resistors + pre-amp resistors to lower the resistor noises.

I will start soon making some noise analysis on:
- different power supplies
- pre-amps
- coils and coil shieldings

I will also take milliWatt®™ PI coil pulses into account to reduce inherent noise and mineral soil magnetization.

Aziz

[putrechigi]

hi

hi at all
see this video peraps is intresting for you

http://www.youtube.com/watch?v=XCKThqg7h5E

best reguards

[1843]

hi
I dont suppose there is a sd2000 pcb in the making ...
Good try at the sd2000 on breadboard ..now i know I shouldnt try it as yet..
Have you try shielding the front end stage ?? or anything else ??
Anyways thanks

Hi,
No, I didn't shield anything. In fact when I saw it works in motion mode, didn't try anymore on it... I like non-motion MDs...

Best regards,
1843

[gef12]

Ye roger that .. I would have more benefit with motion mode as it gives me a good idea of where small targets lie .. especially nuggets... just cant visuallize how a non-motion would work or in what scenario ... have only used motion md's
thanks anyways

[eclipse]

1843 did you use the same components as those on the schematic
some of them like LT1057 have very good parameters and if you use
alternative the circuit could suffer from noises from such components
I also want to build the it, but I am novice, don't know if i could do it.
I am making board for it, 3 days just the power supply part ready

[1843]

1843 did you use the same components as those on the schematic
some of them like LT1057 have very good parameters and if you use
alternative the circuit could suffer from noises from such components
I also want to build the it, but I am novice, don't know if i could do it.
I am making board for it, 3 days just the power supply part ready

No! As I said the mine had many difference.... I used an LT1054 for power supply,
LF356 instead of LT1057... etc.

Best regards,
1843

[eclipse]

At least we know the schematic is correct, which is good ...

[external9]

sd2000

hello Would explore how useful this is the metal detector?