MINELAB F1A4 ex military metal detectors - tips, settings, questions

[AuMan]

Its magic! don't question it lol.

Also, I just got done putting an F1A4 back together, that was supposed to be modified to level 2... everything looked good from the outside..

Toggles were in the correct places, volume threshold and tone too, however the guy noticed right away that flipping the switches had no effect on the detector, volume knob worked fine, but nothing else..

he dropped by at 8:14am this morning, opened the front panel (none of the "mod" components (toggles, pots) were connected.. so basically the guy charged $650 to open the case, drill some holes in the front panel mount some toggle switches, and pots and apply a few labels...

none of the coil plug wires were soldered properly, and actually had to be de-soldered from the PCB and replaced as half the plastic sheath was melted off the wires.
also he had hooked up the speaker to headphone jack.. (uses more power)

Anyway, pro tip, use someone with a good rep, not a cheap price..

Hey Downhalo, do you know who this supposed modder is? I take it that it was not done by the guy who does them for Jack Lang? The only place to get a level 2 modified f1a4 is from Jack Lang, anyone else claiming to be upgrading detectors to level 2 could be infringing on someone elses hard earned intellectual property.
How was a speaker still in the detector when you claim that there was pots installed on the front panel? There is not room for both.
Do the auto-tune and audio reset buttons still work?

You claim to be able to put the magic smoke back in, please identify U17 and explain its function

Regards, AuMan

 

[downhalo]

Well i fixed what could be fixed, and left it at that, told him to contact the guy... to me it looks like he got so far, then forgot to finish the job (or just didn't bother)
either way, dodgy work..

I suggested he contact the guy at detectormods.com

 

[downhalo]

Its magic! don't question it lol.

Also, I just got done putting an F1A4 back together, that was supposed to be modified to level 2... everything looked good from the outside..

Toggles were in the correct places, volume threshold and tone too, however the guy noticed right away that flipping the switches had no effect on the detector, volume knob worked fine, but nothing else..

he dropped by at 8:14am this morning, opened the front panel (none of the "mod" components (toggles, pots) were connected.. so basically the guy charged $650 to open the case, drill some holes in the front panel mount some toggle switches, and pots and apply a few labels...

none of the coil plug wires were soldered properly, and actually had to be de-soldered from the PCB and replaced as half the plastic sheath was melted off the wires.
also he had hooked up the speaker to headphone jack.. (uses more power)

Anyway, pro tip, use someone with a good rep, not a cheap price..

Hey Downhalo, do you know who this supposed modder is? I take it that it was not done by the guy who does them for Jack Lang? The only place to get a level 2 modified f1a4 is from Jack Lang, anyone else claiming to be upgrading detectors to level 2 could be infringing on someone elses hard earned intellectual property.
How was a speaker still in the detector when you claim that there was pots installed on the front panel? There is not room for both.
Do the auto-tune and audio reset buttons still work?

You claim to be able to put the magic smoke back in, please identify U17 and explain its function

Regards, AuMan

The speaker was removed, the speaker wires coming from the PCB were connected to the headphone jack.. sorry wasn't clear.

U17? LOL nope.. no idea.. the trick with the magic smoke is replacement parts and a JBC CD-2BB

 

[nuggethunter]

Jee all these numbers and letters.
I think we need r2d2. He would know what to do.

 

[qldnuggytom]

Indeed... hard to beat it for the price, (maybe the whites SPP) ..

I've got both, modified and unmodified, I prefer the modded machine (just because)..

Kind of wish I had gone your route of buying the B & Z booster, built my own, and they work great, but I have about 8 versions and I spent more than $195 on the prototypes before i got it just right lol..

oh well next time! then again, $195 for $30 in parts.. maybe not..

Also, Minelab do not service or support the F1A4 any more, so i guess if you do let the magic smoke out, you're screwed (unless you're me) I can put it back in.

I know where you are coming from but have you added up man hours to your home built booster as well?? what I mean is I am a trades man concreter and carpenter and respect the skill of the chosen profession someone else has chosen to do so as for the technical stuff and soldering which I know is not hard but its the expertise and skill I pay for I got everything very quick good manufacturing and all
and I say you spent $195 not in wasted parts but in gained skill for 195 you now know how to make a booster that works my friend im sure an electronics class teaching how to make boosters would cost more then $195 you got a bargain

 

[qldnuggytom]

Indeed... hard to beat it for the price, (maybe the whites SPP) ..

I've got both, modified and unmodified, I prefer the modded machine (just because)..

Kind of wish I had gone your route of buying the B & Z booster, built my own, and they work great, but I have about 8 versions and I spent more than $195 on the prototypes before i got it just right lol..

oh well next time! then again, $195 for $30 in parts.. maybe not..

Also, Minelab do not service or support the F1A4 any more, so i guess if you do let the magic smoke out, you're screwed (unless you're me) I can put it back in.

I know where you are coming from but have you added up man hours to your home built booster as well?? what I mean is I am a trades man concreter and carpenter and respect the skill of the chosen profession someone else has chosen to do so as for the technical stuff and soldering which I know is not hard but its the expertise and skill I pay for I got everything very quick good manufacturing and all
and I say you spent $195 not in wasted parts but in gained skill for $195 you now know how to make a booster that works my friend im sure an electronics class teaching how to make boosters would cost more then $195 you got a bargain

 

[AuMan]

Well i fixed what could be fixed, and left it at that, told him to contact the guy... to me it looks like he got so far, then forgot to finish the job (or just didn't bother)
either way, dodgy work..

I suggested he contact the guy at detectormods.com

Ok so I take it that he got some back yarder to do it, not the guy who does them for Jack Lange. I would be interested to know who it is, pm me if you don't want to post it publicly.

U17? LOL nope.. no idea.. the trick with the magic smoke is replacement parts wink and a JBC CD-2BB

Well the trick to replacement parts is to know what their part numbers are and what function they perform within the detector to know that you might need to replace that particular part. As for the JBC CD-2BB, well any decent temperature controlled soldering iron will do, whats important is the person driving it. You might also need some other soldering equipment when working with SMD components to prevent the pads from lifting off the board during component removal.
FYI the part U17(this is its refdes) is an rs232 interface.

Now to your frequency mod, when you switch to your other frequencys,
how long does the auto-tune take to complete?
How long for the audio reset to complete?
How long for the start up sound to complete?
What happens to the tone?
What happens when you flick your frequency switch from a higher frequency to a lower frequency?
What happens to the transmit and receive sample timings?
PS, I know all the answers to these questions

Nuggethunter, if you ever have any problems with your machine, please contact the person you bought it off and it will be rectified ASAP.

Regards, AuMan

 

[nuggethunter]

Yes for sure.
I wad more than happy with the service I got and the detector.
Id be sure to return to the same people for warranty.

 

[downhalo]

Well i fixed what could be fixed, and left it at that, told him to contact the guy... to me it looks like he got so far, then forgot to finish the job (or just didn't bother)
either way, dodgy work..

I suggested he contact the guy at detectormods.com

Ok so I take it that he got some back yarder to do it, not the guy who does them for Jack Lange. I would be interested to know who it is, pm me if you don't want to post it publicly.

U17? LOL nope.. no idea.. the trick with the magic smoke is replacement parts wink and a JBC CD-2BB

Well the trick to replacement parts is to know what their part numbers are and what function they perform within the detector to know that you might need to replace that particular part. As for the JBC CD-2BB, well any decent temperature controlled soldering iron will do, whats important is the person driving it. You might also need some other soldering equipment when working with SMD components to prevent the pads from lifting off the board during component removal.
FYI the part U17(this is its refdes) is an rs232 interface.

Now to your frequency mod, when you switch to your other frequencys,
how long does the auto-tune take to complete?
How long for the audio reset to complete?
How long for the start up sound to complete?
What happens to the tone?
What happens when you flick your frequency switch from a higher frequency to a lower frequency?
What happens to the transmit and receive sample timings?
PS, I know all the answers to these questions

Nuggethunter, if you ever have any problems with your machine, please contact the person you bought it off and it will be rectified ASAP.

Regards, AuMan

Part numbers are only a problem if minelab have sanded them off, plus the white paint... I've got a number of the F1 units, so parts "for my own machine" isn't a problem.
303D rework station helps with that SMD stuff..

Decent temperature controlled soldering station, Yep hakko, Weller they're great.. Pads lift because idiots use force or higher temperatures to create thermal capacitance.
I've never had that problem with the JBC so i mention it.. My cheap ass Rhino tools soldering station does the job with the right tip, but compared to the JBC, its not worth the mention.

"Now to your frequency mod" which one? the one i adapted from the SD2000? that mod? the one from minelab mods?
I flip the switch, and it takes 2-3 seconds for the machine to calm its shit..
Audio reset? you're asking a question that can be answered by reading the manual.. (70 seconds)
Start up (10 seconds)
"what happens to the tone" ascending tone x3
"switching from 3mhz back tends to make the machine freak out a little.
"what happens to the transmit and receive sample timings?" wouldn't know, but would like to
And now, in knowing the answers to all the above yourself (i'm sure none of mine are correct )

Now you seem to be on the attack, may i ask why?... I'm not providing "incorrect" or misleading information, I don't mod for money nor do i "sell my services"
I mod my own gear, its fun its a hobby.. You're killing the fun...

qldnuggytom, You are correct.. The time and money spent getting it exactly the way i want it, I would have been much better off buying the B&Z, but its a hobby I enjoy playing around..

 

[Guest]

Hey AuMan seeing as though you know everything do you know why the person modding the F1A4 for Jack Lange is anonymous?
Sounds like you have a personal or financial interest in them?
How would one modder go claiming infringement on another modder when they are just modifying someone elses original intellectual property anyway. It would be hard to prove that one electronics whizz found a mod no one else could when they are working on the same & someone elses "engine".

Keep up the posts downhalo - not looking at doing mods etc. but its interesting & I'm sure will help someone who wants to have a go at it.

 

[Sparra]

Well i fixed what could be fixed, and left it at that, told him to contact the guy... to me it looks like he got so far, then forgot to finish the job (or just didn't bother)
either way, dodgy work..

I suggested he contact the guy at detectormods.com

Ok so I take it that he got some back yarder to do it, not the guy who does them for Jack Lange. I would be interested to know who it is, pm me if you don't want to post it publicly.

U17? LOL nope.. no idea.. the trick with the magic smoke is replacement parts wink and a JBC CD-2BB

Well the trick to replacement parts is to know what their part numbers are and what function they perform within the detector to know that you might need to replace that particular part. As for the JBC CD-2BB, well any decent temperature controlled soldering iron will do, whats important is the person driving it. You might also need some other soldering equipment when working with SMD components to prevent the pads from lifting off the board during component removal.
FYI the part U17(this is its refdes) is an rs232 interface.

Now to your frequency mod, when you switch to your other frequencys,
how long does the auto-tune take to complete?
How long for the audio reset to complete?
How long for the start up sound to complete?
What happens to the tone?
What happens when you flick your frequency switch from a higher frequency to a lower frequency?
What happens to the transmit and receive sample timings?
PS, I know all the answers to these questions

Nuggethunter, if you ever have any problems with your machine, please contact the person you bought it off and it will be rectified ASAP.

Regards, AuMan

Part numbers are only a problem if minelab have sanded them off, plus the white paint... I've got a number of the F1 units, so parts "for my own machine" isn't a problem.
303D rework station helps with that SMD stuff..

Decent temperature controlled soldering station, Yep hakko, Weller they're great.. Pads lift because idiots use force or higher temperatures to create thermal capacitance.
I've never had that problem with the JBC so i mention it.. My cheap ass Rhino tools soldering station does the job with the right tip, but compared to the JBC, its not worth the mention.

"Now to your frequency mod" which one? the one i adapted from the SD2000? that mod? the one from minelab mods?
I flip the switch, and it takes 2-3 seconds for the machine to calm its shite..
Audio reset? you're asking a question that can be answered by reading the manual.. (70 seconds)
Start up (10 seconds)
"what happens to the tone" ascending tone x3
"switching from 3mhz back tends to make the machine freak out a little.
"what happens to the transmit and receive sample timings?" wouldn't know, but would like to
And now, in knowing the answers to all the above yourself (i'm sure none of mine are correct )

Now you seem to be on the attack, may i ask why?... I'm not providing "incorrect" or misleading information, I don't mod for money nor do i "sell my services"
I mod my own gear, its fun its a hobby.. You're killing the fun...

qldnuggytom, You are correct.. The time and money spent getting it exactly the way i want it, I would have been much better off buying the B&Z, but its a hobby I enjoy playing around..

I thought the same thing as I read the posts and also notice that you have not done an intro....I know nothing about electronic's but downhalo's posts and illustrations are very easy to read and follow and I am sure they would be of great benefit to someone on the brink of having a go themselves...Keep up the good work...These are just my thoughts...

Cheers...Sparra

 

[downhalo]

Hey AuMan seeing as though you know everything do you know why the person modding the F1A4 for Jack Lange is anonymous?
Sounds like you have a personal or financial interest in them?
How would one modder go claiming infringement on another modder when they are just modifying someone elses original intellectual property anyway. It would be hard to prove that one electronics whizz found a mod no one else could when they are working on the same & someone elses "engine".

Keep up the posts downhalo - not looking at doing mods etc. but its interesting & I'm sure will help someone who wants to have a go at it.

Indeed i will keep posting.

Honestly, the only mods i would recommend would be the headphone jack, quick track button... Maybe the coil connector if you want to play with more coil options.
But even without any of the above, these machines are or were cheap, prices seem to have gone up since word has gotten around.

Now i mentioned detectormods.com for one reason, I had my GP 3000 modded a few years ago by him, and it turned out brilliant (very pricey though)

Unfortunately it isn't always easy to find out if "modder A is better than modder B, or if modder C is cheaper because he does crap work, I got good results using detectormods, But I've heard horror stories from people saying they send off a perfectly functioning GPX 4500 and got back a noisy uncontrollable peace of crap, user error or modder balls up? who knows..

Do your home work, or leave it alone, the first nugget i found was with a stock standard F1A4, 0.51 gram bit.. probably less than 5" in depth.. they work.

Since Minelab no longer support or service these units, so it most cases you're probably better off leaving things be.

tthat said you're not going to kill your machine by changing the headphone jack or coil connector... or head to http://au.rs-online.com/ some plugs, make an adapter..

 

[downhalo]

Well i fixed what could be fixed, and left it at that, told him to contact the guy... to me it looks like he got so far, then forgot to finish the job (or just didn't bother)
either way, dodgy work..

I suggested he contact the guy at detectormods.com

Ok so I take it that he got some back yarder to do it, not the guy who does them for Jack Lange. I would be interested to know who it is, pm me if you don't want to post it publicly.

U17? LOL nope.. no idea.. the trick with the magic smoke is replacement parts wink and a JBC CD-2BB

Well the trick to replacement parts is to know what their part numbers are and what function they perform within the detector to know that you might need to replace that particular part. As for the JBC CD-2BB, well any decent temperature controlled soldering iron will do, whats important is the person driving it. You might also need some other soldering equipment when working with SMD components to prevent the pads from lifting off the board during component removal.
FYI the part U17(this is its refdes) is an rs232 interface.

Now to your frequency mod, when you switch to your other frequencys,
how long does the auto-tune take to complete?
How long for the audio reset to complete?
How long for the start up sound to complete?
What happens to the tone?
What happens when you flick your frequency switch from a higher frequency to a lower frequency?
What happens to the transmit and receive sample timings?
PS, I know all the answers to these questions

Nuggethunter, if you ever have any problems with your machine, please contact the person you bought it off and it will be rectified ASAP.

Regards, AuMan

Part numbers are only a problem if minelab have sanded them off, plus the white paint... I've got a number of the F1 units, so parts "for my own machine" isn't a problem.
303D rework station helps with that SMD stuff..

Decent temperature controlled soldering station, Yep hakko, Weller they're great.. Pads lift because idiots use force or higher temperatures to create thermal capacitance.
I've never had that problem with the JBC so i mention it.. My cheap ass Rhino tools soldering station does the job with the right tip, but compared to the JBC, its not worth the mention.

"Now to your frequency mod" which one? the one i adapted from the SD2000? that mod? the one from minelab mods?
I flip the switch, and it takes 2-3 seconds for the machine to calm its shite..
Audio reset? you're asking a question that can be answered by reading the manual.. (70 seconds)
Start up (10 seconds)
"what happens to the tone" ascending tone x3
"switching from 3mhz back tends to make the machine freak out a little.
"what happens to the transmit and receive sample timings?" wouldn't know, but would like to
And now, in knowing the answers to all the above yourself (i'm sure none of mine are correct )

Now you seem to be on the attack, may i ask why?... I'm not providing "incorrect" or misleading information, I don't mod for money nor do i "sell my services"
I mod my own gear, its fun its a hobby.. You're killing the fun...

qldnuggytom, You are correct.. The time and money spent getting it exactly the way i want it, I would have been much better off buying the B&Z, but its a hobby I enjoy playing around..

I thought the same thing as I read the posts and also notice that you have not done an intro....I know nothing about electronic's but downhalo's posts and illustrations are very easy to read and follow and I am sure they would be of great benefit to someone on the brink of having a go themselves...Keep up the good work...These are just my thoughts...

Cheers...Sparra

Appreciate that Sparra.

Like i said, I'm no pro modder LOL Laughable for anyone to get that idea..

But if my fiddling saves someone some money, time, or a blown machine all the better...

I don't post anything I haven't tested myself.. which is why you wont see any timing/frequency mod info come from me, the frequency mod on my bench F1A4 works, but makes the machine play up (false signals etc) for 5-10 seconds after switching.. Iffy result in my opinion so i'm not gonna mess with it..

 

[AuMan]

Downhalo, I don't mean to spoil your fun, just trying to educate you a little
From a newby's perspective it would indeed appear that you are a guru on these things. Be careful, because a little bit of knowledge in the wrong hands can be dangerous.

These are my observations from the frequency mod you have attempted, as in substituting the crystal found next to the large 40 pin dip chip.
The original frequency is 4mhz.
Lowering it to 2mhz does the following,
When it is switched from the original crystal, the machine re-boots,
re-boot time is doubled,
noise cancel time is doubled(140 seconds)
Audio reset time is doubled,
The tone goes all gargly,
Nothing changes with the transmit and receive timings.
Perhaps I have done something wrong?

By all means changing the coil plug and headphone jack is absolutely necessary. There is no switch required to use dd and mono coils if wired correctly, which you have done. However if you wanted to use a dd coil as a mono coil, then you do need a switch.

The audio booster you are making is good. I think the same seller also sells a small 5v regulator board, which should consume less current than the 5v regulator you are using.

Regards, AuMan

 

[downhalo]

AuMan, I really appreciate the info.. Nice to have the info from someone a little more in the know..

And i know from experience that a little info in the hands of a newby (myself) can be a bad thing, and while I'm happy to eat the cost of my tinkering, I guess it wouldn't hurt to put up a warning message now n then lol.

My first attempt at modding the F1, ended in burning out the battery pack circuit... could have been worse :|
Also I appreciate you confirming my coil plug wiring was correct even though it's been tested, you never really know!...

I do have a question for you..

In your opinion, how effective are the frequency changes? is it something I should bother with? I've read that without altered timings it isn't worth it..

Anyway I'll keep tinkering!

 

[KarlS]

Downhalo, I don't mean to spoil your fun, just trying to educate you a little
From a newby's perspective it would indeed appear that you are a guru on these things. Be careful, because a little bit of knowledge in the wrong hands can be dangerous.

These are my observations from the frequency mod you have attempted, as in substituting the crystal found next to the large 40 pin dip chip.
The original frequency is 4mhz.
Lowering it to 2mhz does the following,
When it is switched from the original crystal, the machine re-boots,
re-boot time is doubled,
noise cancel time is doubled(140 seconds)
Audio reset time is doubled,
The tone goes all gargly,
Nothing changes with the transmit and receive timings.
Perhaps I have done something wrong?

By all means changing the coil plug and headphone jack is absolutely necessary. There is no switch required to use dd and mono coils if wired correctly, which you have done. However if you wanted to use a dd coil as a mono coil, then you do need a switch.

The audio booster you are making is good. I think the same seller also sells a small 5v regulator board, which should consume less current than the 5v regulator you are using.

Regards, AuMan

4 MHz crystal provides clock for microprocessor. Lowering frequency 2 MHz will half processing speed therfore functions like audio reset will take twice long.
Karl

 

[downhalo]

Downhalo, I don't mean to spoil your fun, just trying to educate you a little
From a newby's perspective it would indeed appear that you are a guru on these things. Be careful, because a little bit of knowledge in the wrong hands can be dangerous.

These are my observations from the frequency mod you have attempted, as in substituting the crystal found next to the large 40 pin dip chip.
The original frequency is 4mhz.
Lowering it to 2mhz does the following,
When it is switched from the original crystal, the machine re-boots,
re-boot time is doubled,
noise cancel time is doubled(140 seconds)
Audio reset time is doubled,
The tone goes all gargly,
Nothing changes with the transmit and receive timings.
Perhaps I have done something wrong?

By all means changing the coil plug and headphone jack is absolutely necessary. There is no switch required to use dd and mono coils if wired correctly, which you have done. However if you wanted to use a dd coil as a mono coil, then you do need a switch.

The audio booster you are making is good. I think the same seller also sells a small 5v regulator board, which should consume less current than the 5v regulator you are using.

Regards, AuMan

4 MHz crystal provides clock for microprocessor. Lowering frequency 2 MHz will half processing speed therfore functions like audio reset will take twice long.
Karl

See, this is why i love electronics.. always some fun facts!

 

[downhalo]

Downhalo, I don't mean to spoil your fun, just trying to educate you a little
From a newby's perspective it would indeed appear that you are a guru on these things. Be careful, because a little bit of knowledge in the wrong hands can be dangerous.

These are my observations from the frequency mod you have attempted, as in substituting the crystal found next to the large 40 pin dip chip.
The original frequency is 4mhz.
Lowering it to 2mhz does the following,
When it is switched from the original crystal, the machine re-boots,
re-boot time is doubled,
noise cancel time is doubled(140 seconds)
Audio reset time is doubled,
The tone goes all gargly,
Nothing changes with the transmit and receive timings.
Perhaps I have done something wrong?

By all means changing the coil plug and headphone jack is absolutely necessary. There is no switch required to use dd and mono coils if wired correctly, which you have done. However if you wanted to use a dd coil as a mono coil, then you do need a switch.

The audio booster you are making is good. I think the same seller also sells a small 5v regulator board, which should consume less current than the 5v regulator you are using.

Regards, AuMan

I assume you're talking about a LM2596 DC-DC buck? probably the wrong one lol...

 

[downhalo]

I'd love to know the actual number of Level 2 modded machines that are out in the world right now.. I'd imagine it can't be more than 4-5...

 

[nuggethunter]

unsure on total.
im 1 of them