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View Full Version : Fluxgate Depth of Penetration


Jan
08-18-1999, 09:14 PM
hmmm.. Sorry for al extra posts...


jan

Carl
11-04-1999, 10:10 AM
From what I continue to read on MD forums the old Compass detectors are the ones to beat for use in nail-infested areas. I've been on the lookout for one at a good price.


- Carl

Carl
11-04-1999, 10:10 AM
From what I continue to read on MD forums the old Compass detectors are the ones to beat for use in nail-infested areas. I've been on the lookout for one at a good price.


- Carl

Carl
11-04-1999, 10:10 AM
From what I continue to read on MD forums the old Compass detectors are the ones to beat for use in nail-infested areas. I've been on the lookout for one at a good price.


- Carl

Carl
11-12-1999, 10:08 AM
>Hi !


>I just started building magnum detector but I can't find following transistors:


>BC 184L


>BC 214L


>and a nightmare :-( BFX 29


>What transistors I could use instead or at least maybe someone had some info about bfx 29 or other?


The way these transistors are used in the circuit makes their types pretty non-critical. Things should work just fine if you use 2N3904's for the NPNs and 2N3906's for the PNPs. The BFX29 is the only one you might want to consider differently - if you're only driving headphones then the 2N3906 should be OK; if you're driving an 8 ohm speaker then you might want to use a TO-220 type PNP (like a TIP32).


Lets us know how it turns out!


- Carl

Carl
11-12-1999, 10:08 AM
>Hi !


>I just started building magnum detector but I can't find following transistors:


>BC 184L


>BC 214L


>and a nightmare :-( BFX 29


>What transistors I could use instead or at least maybe someone had some info about bfx 29 or other?


The way these transistors are used in the circuit makes their types pretty non-critical. Things should work just fine if you use 2N3904's for the NPNs and 2N3906's for the PNPs. The BFX29 is the only one you might want to consider differently - if you're only driving headphones then the 2N3906 should be OK; if you're driving an 8 ohm speaker then you might want to use a TO-220 type PNP (like a TIP32).


Lets us know how it turns out!


- Carl

Carl
11-12-1999, 10:08 AM
>Hi !


>I just started building magnum detector but I can't find following transistors:


>BC 184L


>BC 214L


>and a nightmare :-( BFX 29


>What transistors I could use instead or at least maybe someone had some info about bfx 29 or other?


The way these transistors are used in the circuit makes their types pretty non-critical. Things should work just fine if you use 2N3904's for the NPNs and 2N3906's for the PNPs. The BFX29 is the only one you might want to consider differently - if you're only driving headphones then the 2N3906 should be OK; if you're driving an 8 ohm speaker then you might want to use a TO-220 type PNP (like a TIP32).


Lets us know how it turns out!


- Carl

Eric Foster
11-13-1999, 05:10 AM

Eric Foster
11-13-1999, 05:10 AM

Eric Foster
11-13-1999, 05:10 AM

junkie
12-16-2002, 08:25 AM
How deep can Carl Moreland's Fluxgate Gradiometer penetrate?

Any one with an idea?

Carl
12-18-2002, 11:25 AM
Depends on the size of the target. Also, unlike with a metal detector, solid objects are easier to detect than, say, a hollow can. I believe on a large cast iron target (size of an auto engine) I was getting 10-15 feet, don't recall exactly.

junkie
12-20-2002, 12:49 AM
Carl,

Thanks for the reply.

By the way, am looking for a Earth Resistivity Meter with a higher voltage output. O have read like Geotrade's GTR-2 with an optional DC-Converter. I think this give a higher voltage otput. Do you have any idea how this is done or any web site you can poin me to?

Thanks again.