Bounty Hunter and Fisher F2/F4 Metal Detection Circuits

[turtlefoot]

Here is probably a stupid question but here it is anyway. Since the coils are interchangable on Bounty Hunter models along with being interchangable with the Fisher F2 and F4, does this mean that the detection circuits are the same/similar? I understand that some have micro computers and some do not, but what do the micro computers control, the detection or processing of the detection information? Just curious.

Doug

 

[mwaynebennett]

Inside each BH with a microprocessor is a magic gnome that is using a satellite link to download "adult" images etc. No actually, there have to be various caparisons made at many megacycles per second. The processor is measuring the average ground conditions and then compares those averages to targets it encounters. The properties of the target are then compared to values stored in the BH and based upon triangulation math (for depth) and the electromagnetic properties of the target, the processor then has to send instructions to a sound generator and to either an LCD driver circuit (depth display and likely ID) or to a digital to analog converter to drive the meters with needles. etc. It really is very sophisticated and all this is happening very fast.

Regarding the similarities of the circuits, I think each coil has a transmit coil and a receive coil. It is likely that the driver circuits and receiver circuits in both brands use similar methods to transmit and receive. How each deals with the received signals is most likely where the difference lies.

Mark
Elite 2200
Pioneer 505
WA St.

 

[turtlefoot]

That's what I was wondering. I was trying to understand how the same coil would work on a Bounty Hunter Fast Tracker, Pioneer 505 and on a Fisher F4. I know the Fast Tracker is an analog machine with no meter of any sort (beep and dig). The Pioneer seems to have an LCD that gives the probable target and depth and the F4 looks like it has a "number" system and other doo-dads. I was curious if the micro computer was seperate from the detection circuit which allowed the coils to be interchangable or how it was possible.

Thanks,
Doug

 

[doc-jim]

A coil is more like an Antenna than anything else.... It has transmit & receiver loops and not much of anything else..
Like AM or FM radio different antenna work better than others as they are "tuned" for frequency. Metal detectors of similar frequency can use similar coils.... Beyond that you can have VERY different machines with all kinds of circuits for different modes & filters but they can have the same Transmit/Receive coils....
So, while the COIL may be identical, the machines may be far different from each other in how they process the info. Since most hobby machines run around they same frequency the coils are mostly the same design, BUT!!!! the way they are wired or the pin configuration may not let them just interchange "Plug & Play" style, But if you can find the correct leads, It is as simple as hooking up 2 antennas. One Transmit Coil Lead, One Receiver coil lead & perhaps a ground makes the other 2 connections, but may be 2 wires per loop PLUS a ground to reduce interference. I had a link to a site with a torn down coil showing guts, but cannot find right now...
The bottom line is. Coils are simply two antennas, tuned to frequency range(s) of the transmitter or the receiver. DOC

 

[turtlefoot]

Thanks for the info DOC. I think I understand things a bit better.

Doug

 

[BH_Landstar_]

Try this link >>> pin outs - BH Coil <<<

 

[themartaman]

There are other differences. The F5 coil does not work on the F4. F70 and F75 coils only work with those 2 and the similar Teknetics models. The F5 coils are the same as Teknetics Greek series but do not have screw on connectors. Why, who knows.