Minelab Gold detector SD and GP series mods

[Woody.au]

I have just completed some more mods for the SD series of detectors and these mods could also be applied to the GP series giving superior depth over the stock standard models. So far the front end mods on the SD series have been a great success with up to 30% depth improvement and near 100% sensitivity improvement on small Gold. My latest series of modifications involve modifying the output stage feedback loop to massively increase the coil voltage. This involves changing the front end switching Fets,the output fets, the voltage stabilization fet, the reservoir capacitor, both blocking diodes and load resistors. Another modification was to convert the detector to run on a higher voltage like 12 volts and thus enable up to 800 volts across the coil. These modifications can be used on the GP series as well as the SD detectors. It involves running 2 power supply rails, one to the low level stages and one to the output stage. This involves cutting the positive groundplane of the PC board and adding a few low ESR capacitors to keep the high power switching current from modulating the low level supply.
Other changes such as using Fast but soft recovery diodes around the output stage result in a much smoother threshold as demonstrated in the SD detectors that have been modified. If you are interested in the whole procedure to do these modifications then let me know as there is a bit of work in writing up and putting up photos of the various modifications.

[wyndham]

differences in sd models

Woody i don't mean to hijack your thread but you seem to understand the ML's very well. I recently saw a sd2100 for sale for $900 and new ones for $1695. Are there different versions of the 2100 and if there is a cost/benifit ratio where does that lean. there seems to be thought that the sd series had better depth and that outweighs the ground bal in latter models.I'm trying to decide between the sd 2100 the GS5 and the yet to be released Dave Emery PD or a used ML 3000 or 3500. The price of the 2100 looks good but maybe because of my lack of knowledge. Thanks Wyndham

[Woody.au]

Hi,

After talking to Dave Emery for 2 hours on the phone today I must say wait for his Nemesis detector to hit the market.I had the near full technical run down on how his detector works and I think it will beat every other brand of detector on depth and discrimination. I will not post any of the technical details due to the fact that a certain company is trying its hardest to sneak a peak at his new design. If you can get a 2000 or 2100 under $1000 then that is a good deal. Also I hear that Minelab are getting ready to release their new GPX4500. When Dave's detector hits the market the *** is going to drop out of the pricey end of the market so take that into account.

My current modifications on the SD2000 beat all the GP series on depth and near match the sensitivity of the GPX4000. So why would you spend $6000 on a GPX when a SD2000 + mods will cost near $1250?

[wyndham]

Thanks for the Heads up, don't need to spend the money quite yet so I'll wait til all the apples fall, later Wyndham

[mangobay]

Hello Woody,

I have SD2100v2 and would like to know the modification cost.

Thanks,

BTW or u can contact me at [email protected]

[kennyg123]

SD / Gp mods

Hi Woody,

I have a gp-extreme. Very interested in your mods. What will your how to data cost?

Thanx

Kenny

[Unregistered]

Woody GP-Extreme

Hi Woody

I have GP-Extreme and would like to know what modifications and cost.

Thanks Mark

[kennyg123]

Mods

Hi Woody,

May I get some info regarding your mods?

I can be reached at
[email protected]

[porfirio]

Hi Woody

Also I have GP-Extreme and would like to know what modifications and cost.

Thanks Bruno.

My email:[email protected]

[Unregistered]

Bugger lost my password,

I have a heap of new mods for the SD2000 and mods for the 2100 and 2200... The 3000 series is presently not on the mod list as it is a ***** to work on.

Email me at vk3kcg (at) amsat.org if you want some mod heads up.

I have a new signal sharpening mod and a variable ground balance mod that seem to work extremely well. By feeding in the amount of ground balance for different ground types one can get a huge difference in depth and sensitivity. I have also upgraded the front end Fet mod and a new filter mod that makes the detector give a better signal on small Gold.

[Unregistered]

woodys site

I just sfound this on the web http://detectormods.com looks like woodies site.