Minelab SD2000 tips, settings, questions

[DavePerth1990]

Something that will get maximum depth for my little old detector. I have been told DD coils will give less noise on my my machine.

I currently have the Minelab 11 inch DD and the big 18 inch Dustbin lid green mono coil. The mono coil is crazy loud all the time and seems hard to use, while the 11 inch doesn't seem to get deep enough. I'm looking for big nuggets only as deep as possible with my machine.

Cheers in advance.

 

[micks nugget]

hi dave
I run a mono 18 ' anti interference on my 2000 with pretty good results
I feel it gives more depth than a dd
kind regards mick

 

[axtyr]

Hi everyone.

I have just purchased a SD2000 and I want to do some maintenance on it. As anyone who has opened their detector will know, all the components are covered in paint which makes them very difficult to identify. I have only opened my case but not removed the circuit boards as yet.

I would like to know if anyone out there has done their own maintenance and if so, can they let me know what value the capacitors are on the circuit. I want to start by replacing those components. There are 5 that I can see and I would like to know if anyone knows what value they are and which way the polarity goes on the board. If I scrape them to get the paint off, or use paint stripper then I could possibly remove the identification off them.

If you could also tell me what other components should be replaced on a regular basis I would greatly appreciate it, especially where these components are located on the circuit board.

Woody from Link Technologies also indicated the following below.

On the 2000 change the input diode on the coil drive to a new lower loss ultrafast with soft recovery. Change the 2 irf720 fets for something with lower on resistance and higher voltage rating. Change the p and n rx fets to low c and r types. n is 200 v rated p can be 20 v rated. put in a 3.2 Mhz xtal and you have a very good detector.

I would also like to know if anyone has done this themselves and which components and values they used for these replacement parts.

Hoping to hear from someone soon.

Axtyr.

 

[joe]

Hi Axtyr, have a look at the schematic, it has the values of the caps your are looking for. I had no need to do any part replacement after 15 years yet. Masquerading by paint and non-substitute values of components due to IP protection.

Are the diagrams accurate ? Not sure? Is it a double layer circuit board - possibly by the looks of it. Are there better components out there? Sure check minelab mods website. If the detector is faulty then I would attempt maintenance otherwise you could give four self unnecessary headache
https://www.dropbox.com/s/bta5myp0kjyrnpn/sd2000schematic%20%281%29.pdf

Cheers mate,

 

[axtyr]

Joe.

I downloaded the schematic some time ago but unless you have a background in electronics it is very difficult to follow precisely and know exactly where each component is on the boards. The values of the caps are there but not the voltages. This detector is now 19 years old and I have no idea what it has been subjected to, and I want to subject it to 8V. The dielectric inside all capacitors degrades over time so I would prefer to know that the caps are capable of taking the extra voltage. If I wasn't gong to increase the input voltage then I wouldn't bother replacing them.

I am really trying to find out if some SD2000 users required some sort of maintenance and if so, what parts were replaced. I intend installing some mods myself and I only want to dismantle the unit once. At least I now know of one person who has had 15 years of use without any problems.

Thanks.

 

[joe]

No prob, Axtyr

Just be careful running 8v as the LM358 low power dual operational amplifier has max in 7v,

 

[axtyr]

Thank you Joe. I will keep running it on 6V until I can ascertain a proper voltage. The biggest confusion I have found is some people state "after the mods are installed you will need to run the detector at 7.3V". Others I have read about just run the detector at 7.3V without stating if the detector has been modified or not. I have also read that some run it at 8V and others at 8.5V. I have a brand new 12V battery and installed a plastic case on top of it into which I have placed a voltage regulation unit which now gives me the opportunity to run the detector up to more than 10 volts if I'm stupid enough to. For protection the voltage adjustor is below the surface level and must be adjusted using a small screwdriver.

Another confusing aspect is that some people use a 2 X 6V battery setup with their detector. Do you know if this is to double the running time or is it for some other purpose? I usually find that people with SD2100 or SD2200 might use this setup. I want to install the VCO mod but the input voltage of the chip is only a maximum of 7V so I will need to find out if I can power it from a dedicated 5V supply from the circuit board.

I am going out this weekend and I was going to run it at about 8V but now thanks to you I will can that idea.

Thank you.

 

[dave14110]

Hi, don't know heaps on this model. But I know they run 7.3 on 2000 2100 & 2200 but then the GP Extreme was only 6.7
I have heard of people running high but it also damages detector over time so Don't recommend it.

 

[dave14110]

I should of also added many people run a regulated 12v battery rather than 6v standard battery, by doing this it gives peak performance on detector. Coiltek used to sell regulators for this purpose but I can not say if they still do. Also available on fleebay

 

[Guest]

The SD series, according to most including Coiltek, will handle a regulated aftermarket battery voltage of 7.3-7.4v but no higher. The GP series aftermarket batteries are set to 6.7v as they already have an inbuilt regulator.
http://www.coiltekmanufacturing.com.au/accessories-li-ion.html

 

[joe]

Thank you Joe. I will keep running it on 6V until I can ascertain a proper voltage. The biggest confusion I have found is some people state "after the mods are installed you will need to run the detector at 7.3V". Others I have read about just run the detector at 7.3V without stating if the detector has been modified or not. I have also read that some run it at 8V and others at 8.5V. I have a brand new 12V battery and installed a plastic case on top of it into which I have placed a voltage regulation unit which now gives me the opportunity to run the detector up to more than 10 volts if I'm stupid enough to. For protection the voltage adjustor is below the surface level and must be adjusted using a small screwdriver.

Another confusing aspect is that some people use a 2 X 6V battery setup with their detector. Do you know if this is to double the running time or is it for some other purpose? I usually find that people with SD2100 or SD2200 might use this setup. I want to install the VCO mod but the input voltage of the chip is only a maximum of 7V so I will need to find out if I can power it from a dedicated 5V supply from the circuit board.

I am going out this weekend and I was going to run it at about 8V but now thanks to you I will can that idea.

Thank you.

6V smart move mate. If you have a look at the schematics battery feed has Zener diode in parallel to protect or supress excessive voltage + 5% or so, (i would presume) these days they would used IC's as voltage regulator. So although it may run on 7V 7.5V your components are 19 years old as you said and overheating will change their value thus giving you undesired results.

The two 6V batteries would have to run in parralel which would double the capacity amp hours but not voltage. I use one 6V 12amp hour and last all day no problem.

Try some testing "as is" to get the feeling for it and perhaps change coils to mono (noisier but more sensitive)

Best of luck hunting

 

[dave14110]

sorry don't think I explained it very well. The reason many used 12V is it can be regulated to 7.3 for 2000 2100 2200 or at 6.7v for Gp extreme where a 6v I don't believe can not produce 7.3 or not for very long unless maybe tip top battery fully charged.
hopefully this explains better.

 

[axtyr]

The 7.3V batteries appear to be Lithium Ion and purposely built for the detectors. Mine is a 12V Sealed Lead Acid battery. I have set the voltage to about 6.5 volts as that is what is being delivered from the fully charged 6V battery I also have. I am hoping to find something before I try modding the machine and increasing the voltage so that if something does go wrong I at least have an excuse to buy a replacement. Wives can be so unreasonable at times.

Thanks everyone for all your help. I hope to get to the Coiltek detector test site this Saturday and see what the standard machine is capable of. Wish me luck.

 

[elemental09]

Hi Everyone,

I just purchased a Minelab SD 2000 off ebay which "apparently" worked for the previous owner. I assembled the SD 2000 and turn it on... nothing... no power...
apart from when I turn it 'OFF" the 'power light' flashes for 1second.

At first I thought... ok... it must be the Battery... so I purchased a new one... same issue.

I am trying to get my money back... however... I think i am going to have issues with this guy... his response was 'I tested it before posting... it worked fine... maybe its a lose cable'...

Any ideas / suggestions?

I live in Brisbane - does anyone know if a repair store?

Thanks.

Luke.

 

[Keen Ken]

The SD2000 does not have a speaker as I recall, check the head phones,

It might be as simple as a loose wire.

 

[elemental09]

Hi Keen,

I am not been a smarty when I say this... but what does headphones have to do with it? - the device does not have any power at all (it will not turn on)...
or do you mean... plug in some headphones to see if its working at all?

cheers.

Luke

 

[joe]

Hi Luke,give us a picture of your unit being assembled. As Ken said the only way you going to hear anything is through the headphones. Is it modded ? Does it have external speaker? The red light should only come on if your battery is low.

 

[elemental09]

omg... i feel SOOOOOO silly LOL... the 'power light' was not working... and because it had no external speaker I assumed it had no power...
connected my headphones and BAM its working ahahaha

thanks mate!!!!!

 

[Guest]

The light you are talking about should be a low battery light - it won't come on if the battery is ok but illuminates when your battery is low hence the quick 1 second flash when you turn it off.
The headphones could have everything to do with it - check with a known good pair to eliminate them.

 

[Guest]

:lol: looks like me & joe answered your question at the same time you got it sorted yourself.
Good to hear its working.