Minelab Sovereign XS-2A-Pro

[chopz54]

Anyone know the what the spec for the crystal oscillator in the Sovereign XS-2A-Pro is?



Thanks.

[Sean_Goddard]

Sorry, not sure what you mean.

It's a basic 3.915MHz crystal running the micro. That's it!

[chopz54]

The machine has a 4.194304 Mhz o/crystal crudely fitted ---but still wont work.
Could this be the problem? (wrong value)

[Sean_Goddard]

YUP common fault. Change it to a 3.915MHz!

The ORIGINAL xtal IS the 3.915MHz. some people "upgrade" the xtal thereby making the CPU run a litle faster. I have found that this helps the Sov with badly mineralised ground AND thus helps depth a little BUT......As this is effectively "overclocking" the CPU some CPU's wont work at all or stop working ater a few months / weeks whatever due to increased internal stresses.

Change it back and see what happens. Should fix the problem. One more thing you could try is the xtal bypass caps. Try changing the value DOWNWARDS, might kick it into life as te CPU used is quite critical about the value of these caps.

BTW the Elite with the TWO xtals was ML STEALING MY mod. Nice guys huh?

[chopz54]

Thanks for that Sean, just need to find a 3.915MHz o-c.

The machine has no usable tracks(2) from the cpu and to the component just below the jumper the o-c has been mounted on the underside!!!...

[chopz54]

Would a 4.0mhz o/c be ok?-- as the 3.915 seems none existant!

[Sean_Goddard]

Try 3.8 or 3.75

[chopz54]

Nearest I could get was a 3.68. Have got a threshold tone now.
But nothing else!

[chopz54]

Do you think I have gone to low? And it is effecting the rest of the board?

(this was the highest 3.*** one I could get)

[Sean_Goddard]

OK well at least you have a start.

PM me and give me an email address I will send you "something" which WILL help you.

[thcruil]

I'm sorry but i'm finding it hard to believe that sovereign ever used 3.915mhz crystal, when i searched the Internet I came to the conclusion that such crystals never really were produced, so can someone perhaps take a photo of one? I red the datasheet for the microcontroller used in sovereign, and it is stated there that maximum frequency is 4.2mhz, so fitting 4.194304mhz oscillator would be perfect, but maybe it is not necessary and would cause excess batery draining...
I have similar problem, someone clearly fitted 4.194304 Mhz in there, the machine worked fine first, but than started falsing even on lowest sensitivity, so i changed it for 4.0mhz now and it seems fine, however this is really bothering me and i would like to make it as stock as possible. Also in my sovereign xs-2 there was 3 electrolitic capacitors, really dodgy 16v 1000uf samwha brand, i changed those to 25v 1500uf nichicon, and now it registers some small rusty coins, witch came out as iron before, I know that in newer sovereigns there is one 2200uf capacitor in the left lower corner of the pcb, so i want this in my sovereign as well, is this a good idea or should i just leave it alone and it wont improve anything?

[J-ROB]

Also in my sovereign xs-2 there was 3 electrolitic capacitors, really dodgy 16v 1000uf samwha brand, i changed those to 25v 1500uf nichicon, and now it registers some small rusty coins, witch came out as iron before, I know that in newer sovereigns there is one 2200uf capacitor in the left lower corner of the pcb, so i want this in my sovereign as well, is this a good idea or should i just leave it alone and it wont improve anything?

Crystals are available in any frequency desired. While it makes sense to use a standard value, and maybe the 3.915 is standard for some application, maybe ML wanted a harder to come by part for exclusivity.

Incidentally, Samwha makes really good caps. They are the Korean Nichicon licensee, in fact. Depending on the series in question, you could be taking out better caps and putting worse ones in! Further research in datasheets is necessary to know if this is a good idea--it probably isn't.

[thcruil]

Well I did put in HE(M) series, so defiantly better than SG that i found there, they had to be changed anyway, they may be well more than 10 years old, date code is J1A. When i removed one of them there was some residue, maybe its just some water got under it, or maybe it leaked electrolyte.

[thcruil]

Found good photo of the crystal here http://www.geotech1.com/forums/showt...vereign-faulty
It is 3.904mhz, but this is in older sovereign, maybe minelab fitted others in newer units, what values does sovereign GT uses? does anybody know where could I order those obscure value xtals online?