pulse ar III tests

[Esteban]

Hi Max.
Mosfet works cold. Waveforms are OK. I tried different dumper resistors for any coil but....
Do you remember what dumper did you used????
Regards

I remember that E. Foster suggest here to use a variable resistor, try and found the best point. Disconnect the preset, measure and replace for a fix. This is an ilustrative example: if you obtain 376 ohms, so put in serie 330 + 47 ohms. Or 2 resistors of 750 ohms in paralell. Better 1%. The wires must be well fixed between them.

[Geo]

I remember that E. Foster suggest here to use a variable resistor, try and found the best point. Disconnect the preset, measure and replace for a fix. This is an ilustrative example: if you obtain 376 ohms, so put in serie 330 + 47 ohms. Or 2 resistors of 750 ohms in paralell. Better 1%. The wires must be well fixed between them.

Hi Esteban.
I remember it but i have not a potentiometer 2W, so i play with standard resistors until see better waveform on oscilloscope. If the value is critical, then i lose the best point

Regards

[Max]

Hi Max.
Mosfet works cold. Waveforms are OK. I tried different dumper resistors for any coil but....
Do you remember what dumper did you used????
Regards

Hi,
unfortunately I don't remember , too much time... have to check inside, but before I must dig it from garage things...

Will let you know.

Kind regards,
Max

[Geo]

Thank you Max.

Regards

[Max]

Thank you Max.

Regards

Hi Geo,
I dug that XR-71. Found also it's coil with it.

Coil is 380uH. Damping resistor is 390ohm (1watt rated).

About it... it was upgraded to work around 3 times original frequency...

last setup is f=1200Hz , tx width = 125uS, consumption is around 170mA.
Primary delay is switchable 15uS (for shallow targets (e.g. gold rings) at beach) or 25uS (depth mode, with larger coil).

It detects a soda can at 75cm on air.

The use on soil is a bit tricky... with smaller coil, and of course, detect all kind of ceramics!

I remember I made another (but can't find board now) using 1K8Kohm damping instead of 2K2 as schematic, it works good on 400Hz like original.

Kind regards,
Max

[Berti]

air tests

Hello,

Pulse AR III with 1x1m coil

First I tried a redbull can in ALL METAL mode it detect at 80-85cm. This is fair enough.

Then I tried aluminium plate 25cm diameter but... the same results.


what do you think???


Regards

[Max]

Hello,

Pulse AR III with 1x1m coil

First I tried a redbull can in ALL METAL mode it detect at 80-85cm. This is fair enough.

Then I tried aluminium plate 25cm diameter but... the same results.


what do you think???


Regards

Hi,
I think 80-85cm is good with 1mx1m coil, but problem is that Mosha said it's 30cm not 80-85.

Now the problem could be inconsistency in e.g. manifacture of device, so you're lucky and get one that works, and Mosha not.

Otherwise I don't know what to think.

If device works in 30cm range on a can it's totally unuseful, if instead runs over 80cm things are really different and could be interesting for depth search.

I think Mosha and you will find an agreement or explaination about so different performances...

Kind regards,
Max

[Geo]

Hi Geo,
I dug that XR-71. Found also it's coil with it.

Coil is 380uH. Damping resistor is 390ohm (1watt rated).

About it... it was upgraded to work around 3 times original frequency...

last setup is f=1200Hz , tx width = 125uS, consumption is around 170mA.
Primary delay is switchable 15uS (for shallow targets (e.g. gold rings) at beach) or 25uS (depth mode, with larger coil).

It detects a soda can at 75cm on air.

The use on soil is a bit tricky... with smaller coil, and of course, detect all kind of ceramics!

I remember I made another (but can't find board now) using 1K8Kohm damping instead of 2K2 as schematic, it works good on 400Hz like original.

Kind regards,
Max

Hi Max. thank you


regards

[Geo]

Hi,
I think 80-85cm is good with 1mx1m coil, but problem is that Mosha said it's 30cm not 80-85.

Now the problem could be inconsistency in e.g. manifacture of device, so you're lucky and get one that works, and Mosha not.

Otherwise I don't know what to think.

If device works in 30cm range on a can it's totally unuseful, if instead runs over 80cm things are really different and could be interesting for depth search.

I think Mosha and you will find an agreement or explaination about so different performances...

Kind regards,
Max

Hi Max, 85 cm is very poor for a coil of 1x1 m.
Remember what i wrote....Original Superscan detected the coca can at 1.80 M. One person had the soda can on his head and when he passed through the coil then the machine beeps.When he passed without the soda can, nothing beeps.

Regards

[Geo]

Hi Geo,
I dug that XR-71. Found also it's coil with it.

Coil is 380uH. Damping resistor is 390ohm (1watt rated).

About it... it was upgraded to work around 3 times original frequency...

last setup is f=1200Hz , tx width = 125uS, consumption is around 170mA.
Primary delay is switchable 15uS (for shallow targets (e.g. gold rings) at beach) or 25uS (depth mode, with larger coil).

It detects a soda can at 75cm on air.

The use on soil is a bit tricky... with smaller coil, and of course, detect all kind of ceramics!

I remember I made another (but can't find board now) using 1K8Kohm damping instead of 2K2 as schematic, it works good on 400Hz like original.

Kind regards,
Max

Hi Max.
So i believe that i must play with the damping again. Or to try to find a good potentiometer.

Regards

[Berti]

Hi,
I think 80-85cm is good with 1mx1m coil, but problem is that Mosha said it's 30cm not 80-85.

Now the problem could be inconsistency in e.g. manifacture of device, so you're lucky and get one that works, and Mosha not.

Otherwise I don't know what to think.

If device works in 30cm range on a can it's totally unuseful, if instead runs over 80cm things are really different and could be interesting for depth search.

I think Mosha and you will find an agreement or explaination about so different performances...

Kind regards,
Max

I asked what do you think why the results are the same with can and 25x25cm plate.
*Redbull can is thinner than a soda can.

Maybe mosha need to try new one.

Regards

[Max]

Hi Max, 85 cm is very poor for a coil of 1x1 m.
Remember what i wrote....Original Superscan detected the coca can at 1.80 M. One person had the soda can on his head and when he passed through the coil then the machine beeps.When he passed without the soda can, nothing beeps.

Regards

Hi,
yes, sure... with 1mx1m coil I agree is not so fair result... but 30cm... that could be really disappointing to customer.

If can detect a coke can 85cm is not that bad at the end... cause a cache stuff could be found in the 1m range, though is poor result for a PI with 1m frame coil, I agree.

Have no sense using such large coil when much smaller on SMART mds reach same range!

BTW superscan , is truly interesting... I hate that dang ceramics and relative time wasting with bricks etc, otherwise... I'd like that kind of range...

Kind regards,
Max

[Max]

I asked what do you think why the results are the same with can and 25x25cm plate.
*Redbull can is thinner than a soda can.

Maybe mosha need to try new one.

Regards

Redbull is all special...

Also about caffeine content!

I think too that they get a broken one... or defective (bad quality checks).

But also that 85cm range is few for 1m frame, I see much better from very ordinary homemade MDs with 1m coil.

Kind regards,
Max

[pigeon]

hi all

I want to make a 1m coil with adsl cable for PULSE AR III

thank you very much

best time

P.

[Auftragssucher]

???

I have a pulsar III for many years and the 1x1m-coil detects a coke-can in ca. 1.2m (airtest)
But in the ground you got nearly the same results!
And: Bigger targets produces much better results!