Can batterys afect depth

[Sean_Goddard]

Hi Max, I guess that's what I was trying to say all along, it's NOT a cut and dried answer, there is to much we as electronics people can theorise about, but as I said, in PRACTICAL TERMS, I think the answer would be no, or just a percieved depth increase.

I guess if using a bigger capacity battery makes you THINK you are getting more depth, and it appears to work for YOU, then carry on, after all, isn't life all about the freedom to do what YOU choose?

[Max]

Hi Max, I guess that's what I was trying to say all along, it's NOT a cut and dried answer, there is to much we as electronics people can theorise about, but as I said, in PRACTICAL TERMS, I think the answer would be no, or just a percieved depth increase.

I guess if using a bigger capacity battery makes you THINK you are getting more depth, and it appears to work for YOU, then carry on, after all, isn't life all about the freedom to do what YOU choose?

Hi,
yes sure, could be percieved thing only... but I think also at possibility the target MD has impulsive TX stage... in that case having some extra current at peaks could make things different for real also on the stability issue.

Also in a bad design (e.g. bad regulation) having strong current capacity source could change totally detector behaviour... and same when talking about regulators and dropout.

The problem is that we don't know about this specific case... so we cannot say it's something for sure unless we got more informations.

Sure the battery impact on performances is related to supply strategy and current requirements of the unit. Using e.g. an high dropout regulator could lead to worse effects even with original battery kind employed. Having linear regulators , also, make things even worse when thermal effects came in place... warming the inside of box and so giving unwanted thermal drifts appear... and then it's also a huge waste of energy over the regulator (linear/shunt kind of them are very inefficient devices and waste large amount of power) so batteries will be stressed by such approach if not right capacity meet.

Sometimes, in MD with SMPS, things are easy about energy loss, that's minimized, but then problems arise about minimum requirements for batteries cause this strategy become attractive just over an average current requirement level well above the case of e.g. an BandidoII, like in PIs and some big-current-draining VLF/TX-pulsed machines.

The direct consequence is that any low current powered MD will suffer less of battery weakness... if right supply voltage is meet. On the other side... any hi current powered MD will have lot of troubles with battery weakness, both using linear or switching PSU.

I don't know... maybe one can write a book on this topic and even in that book many people will not find the required Y or N answer.

Kind regards,
Max

[urge]

Hi
I do understand the need for detail. Very much so.

I posted a link to a statment first made on an other forum.
If you did not read it, I have cut a pasted the statment.
Try the link a few of my posts back







Yes its true!!!
Sorry John ( Norfolk "W" ) for the Pooooowah pun....Couldn`t resist!

You do actually get more depth if you use rechargeable batteries
Average MAH on a rechargeable is 1300
"Power Plus" gives you 2300MAH
But!!...if you shift on to "VAPEX Tech" you get a massive2900MAH...which gives you an extra 2" on your depth

Pretty good uh



The detector is a goldmax power, from XP. it takes eight AA batterys.
here is a link to the spec of the detector although it might not give every thing you need.
http://www.xpmetaldetectors.com/uk/portail1.html

any thing else you need please ask.

I kind of have guessed that the use of 2900mah batterys could not make a differance.
BUT I came here to ask the guys (you) that love doing this sort of stuff for a stright yes or no.


I am not easly offened, so no worries there.

[Max]

Hi
I do understand the need for detail. Very much so.

I posted a link to a statment first made on an other forum.
If you did not read it, I have cut a pasted the statment.
Try the link a few of my posts back







Yes its true!!!
Sorry John ( Norfolk "W" ) for the Pooooowah pun....Couldn`t resist!

You do actually get more depth if you use rechargeable batteries
Average MAH on a rechargeable is 1300
"Power Plus" gives you 2300MAH
But!!...if you shift on to "VAPEX Tech" you get a massive2900MAH...which gives you an extra 2" on your depth

Pretty good uh



The detector is a goldmax power, from XP. it takes eight AA batterys.
here is a link to the spec of the detector although it might not give every thing you need.
http://www.xpmetaldetectors.com/uk/portail1.html

any thing else you need please ask.

I kind of have guessed that the use of 2900mah batterys could not make a differance.
BUT I came here to ask the guys (you) that love doing this sort of stuff for a stright yes or no.


I am not easly offened, so no worries there.

Hi,
ok you provided enough details now. I saw the link but didn't go there cause lack of time is my second name.

I see this on specs:

8x AA alkaline or rechargeable pack nimh
freq. = 18Khz
motion kind detector
and most important: 50hours with 2300mha

OK, 50 hours mean you have around 45mA current average or a bit less.

The fact unit is supplied with 8 1.5V cells say that uses 12v then will be sure something regulator to down voltage , probably a low-dropout one in XP stuff. That all will give you ability to run effectively detector for long time and stable no matter if exactly 50 hours or 40.

I haven't it's schematics but:
assuming that goldmax power is a VLF (like sure it is cause 18Khz of operating frequency and discrimination issues) and with pulsed TX oscillator , like in some H-bridge config as in other brands, I will say "Y" the fact of using cells with higher capacity could give you effectively an extra boost in this case of 2'' (maybe or maybe less...depending on many factors).

Though surprising there's nothing to surprise if detector works like I've assumed above: any pulsed TX stage will only take advantage of extra current at critical time of generating the pulses. This will enforce enough the TX magnetic field to give you the extra boost.

Also, the extra capacity could give you better stability, but this is another issue.

So, if my statements of above are right guesses on device issues, my answer to your question is "Y" for this case.

Kind regards,
Max

[ivconic]

"...You must understand that the maketing of MD's is full of lies and made-up
terms to sell, as Max says, 30 year old technology. I give you Tesoro!! I have
NOTHING against them, GREAT machines, but they have NOT brought out a truly NEW
design since the Silver Sabre..."


W H A T ???!!!
Sean.....ts,ts,ts...until now i considered you as very up to date man!
First of all...even "old"Golden Sabre presents "quantum jump" from one to another principle, comparing SS, you mentioned!
It is not possible that you didnt know that!?
Skim look at SS and GS schematics will fool some laic to think those are pretty simillar, if not exact...but you not suppose to be laic, Sean oh Sean!!!
You have to posses or make both of mentioned,perform some serious tests and than come here and make some judgements.....
I dont agree with you.
Following latest Tesoro's models i am free to say that they evolved most of all other manufacturers.Mark my words!


"...I guess if using a bigger capacity battery makes you THINK you are getting more depth..."

Using bigger capacity battery makes you DONT think about power drain...you are free to stay on the field much more time without worrying about batteries. Days....not hours!
"More depth"...No! 300mA and 300A will give you same depth, only second one will last much longer.....heh,heh,heh....who needs AA's anymore?
Yet...it is possiblle that device like Garret GTI2500 DO "CARE" about capacity of used batts.
Therefore TX amplitude will be directly dependable of it.
This is the case mostly with models based on uPC,newer,high tech, where uPC control and regulate TX-ed power...
First time you hear about this? Strange!?
Same case is with XP detector, so main question here DOES MAKE SENCE!

[urge]

Thanks Max and others.

I have always run Dry cells like duracell.

I have (but never used) some 2500mah batterys.
I will try them and maybe some 2900mah and let you know.

Once again thanks for your help

[douglas]

What about a regulator change. Can that improve Depth?

Lets say a MD hobby experimenter wanted to get more depth out of his/her machine and they discover that it uses lets say a 7809 regulator and They just happen to have a 7815 lying around in their electronics box. Knowing that the 7809 is 9v and the 7815 is 15v could they just switch out the origional 7809 with the 7815,or would this lead to another a three mile island disaster? Just wondering.

[Sean_Goddard]

Hi Douglas,

I'm NOT trying to be funny, but lets suppose that someone READ the above postings VERY CAREFULLY. The answer is MAYBE, YES, PROBABLY NOT, NO.

It ALL depends on the original circuit design.

Most likely you'd overstress all the components like tantalum capcitors and cause a firestorm, maybe not, one thing is for sure though, you WILL reduce the life of your detector over time.

The light that shines twice as bright burns half as long!

In other words, try it and see, if it works then YAY , if your detector goes up in smoke then the answer was no .

[Max]

Lets say a MD hobby experimenter wanted to get more depth out of his/her machine and they discover that it uses lets say a 7809 regulator and They just happen to have a 7815 lying around in their electronics box. Knowing that the 7809 is 9v and the 7815 is 15v could they just switch out the origional 7809 with the 7815,or would this lead to another a three mile island disaster? Just wondering.

Hi,
it's very strange if you could do that change from e.g. 7809 to 7815 with no pain and without other mods: Sean told you why... depends on circuit.

Very often the regulator output serves as positive rail for many parts that may not tolerate such an increase in voltage.

Critical stuff are not only tantalium caps but also electrolitic caps ... think e.g. if you have 10volt rated stuff and use 15v on them but not only... other sensitive parts could be transistor stages... think e.g. at something driving you audio output stage if it will stay happy with about twice the power to deliver or some digital device also that will not tolerate +15v : think e.g. at some buzzer cap thing rated 12v...

Even if you will not destroy immediately part of them you could have troubles in a few days or weeks ... e.g. electrolitics could take more time to dead but they will be permanently damaged from 50% more voltage in a relative short time than their expected life.

And there's another problem: often the positive rail is employed as reference voltage source too, that means if so you could totally alterate the settings, tunings etc on your device if apply instead +15v... always also this depends on original schematic/design.

The people who make such mods usually know where put hands , where mod will be applied safely and where not. Anyway, if you wanna mod your MD just open a thread in modifications and let good people tell you what have to do if you don't know already.

Kind regards,
Max

[douglas]

thank you for the response.

I will let my "friend" know that it might be a bad idea.

[Sean_Goddard]

Urge, I know John, (Norfolk W) personally and to be honest, he's an EXCELLENT detectorist and a very well read man. The ONLY thing I can think of is that the XP design has the audio stage directly across the battery, and as per the Arado range of machine (and Compass) using a higher capacity battery WILL give a little extra depth as the loading on the circuitry after the regulator is reduced due to the baterries ability to deliver a little poke for longer.

Generally, with machines such as Tesoro, and Whites, this would not be true, all you would get is longer battery life.

Why has no one reverse engineered a French XP machine yet? Not worth it perhaps. Strange because they're supposed to be VERY good machines.