Delta pulse

[Tomas]

Hello, detectorists. Did anybody assembled Delta pulse PI detector? i would like to know somethink about adjusting and tech data about this detector, thanks for all

[JC]

Re: Delta pulse




Hi

The construction of Delta-Pulse doesn't put any probléme.

Concerning R39 and R40 to respect values of the diagram. The XR71 is different on this point and the T8 transistor is a PNP.

Concerning R1 and PR1 authorizes the adjustment of the frequency of the pulse. Delta - Pulse works to 100Hz and the XR71 over of 300Hz. my delta-pulse operates to 400Hz.
I replaced R1 by a 120k.
The frequency is given by the constant of time (R1+PR1)*C1.
If you don't have of oscillo to respect R1 to 680K and replaced PR1 by a strap.
The frequency of beating is not critical if one doesn't pass certain value.

Attention on the printed circuit it is necessary to add a strap between the paw 2 and 6 of the IC8.

Sorry for my english.

Jean-Charles

[Chris]

Re: Delta pulse

Hi Jean Charles

Good & professional look! Great assembling job. Can you post the PCB layout into the forum?

Chris

[JC]

Re: Delta pulse




Thank you very much.

[geo]

Re: Delta pulse

Hi JC. Did you draw the pcb with Protel?
Geo

[Beachcomber]

Where could I find a schematic for the Delta Pulse? n/t

n/t

[Tomas]

Re: Where could I find a schematic for the Delta Pulse? n/t




here is a schematics, also i have XR 71 schematics if you need

[Tomas]

Re: Delta pulse

nice job, and your PCB is perfect, i used older version of PCB and there was an error with vd12 and vd 13, this is why sensivity was so low, after i fixed it sensitivity is growed up and now i need to shield everythnk because it feels everythink around

[geo]

Re: Delta pulse

Now which is the sensitivity for a soda can and with what dimensions of coil?
Geo

[Chris]

Re: Delta pulse

Thank you!

[Beachcomber]

Thanks...The schematic is as nice as the PCB layout pix...awesome!!! n/t

n/t

[Tomas]

Re: Delta pulse

19 cm coil feels 1 inch coil at aproximatelly 20 cm distance in air

[Tomas]

Re: Delta pulse

19 cm coil feels 1 inch coin at aproximatelly 20 cm in air, and the coil is not perfectly made, so i think it could be much better

[JC]

Re: Delta pulse




Hi.

The drawing has been made with WINTYPON.

Now I work with EAGLE.

For the sensitivity :
coke: 70cm
coin of 5F silver: 30cm
gold ring: 20cm

For the coil :
30 turns of 0,35mm enameled wire on 200mm

I replaced
R1(680k) by a 120k.
R7(15k) by a 10k.
R5(2k2) by a 1k
R6(680Ohm) by a 1k.
IRF740 by an IRF840.

It is a good and funny PI

Jean-Charles

[geo]

Re: Delta pulse

I"ll try to build it.Do you have shield at the coil?
Thanks Geo