Delta Pulse

[Geo]

what is the best choice for increasing the Gain of DP , increase the gain of LF357 or add a secondary amplifire between LF357(IC 4) and TL062(IC5 A) ?

This is a big problem. If you will increase the gain then you will have more noise and worst performance. I tried with a second amplifier but without results. Also i changed the gain of LF356 ...7 and TL 0.. but without good results. So who is the solution ????
You must try to change the LF356 with a better IC .... as 5534, AD877 (if i remember ok) etc.
Regards

[kt315]

You must try to change the LF356 with a better IC .... as 5534, AD877 (if i remember ok) etc.

bad idea. NE5534 is not MOS-FET input stage Op Amp and will not working in DP. LF357 is really best then and novatime. please Geo do not mislead... in Delta you can use only MOS-FET opamps. another way you will get the trouble.

[Geo]

You must try to change the LF356 with a better IC .... as 5534, AD877 (if i remember ok) etc.

bad idea. NE5534 is not MOS-FET input stage Op Amp and will not working in DP. LF357 is really best then and novatime. please Geo do not mislead... in Delta you can use only MOS-FET opamps. another way you will get the trouble.

Basically was the different and better IC. I don't remember any type and i did not tried an other type. But after 20+ years i am sure that there are better ic's with lower noise and maybe better frequency cut off.
At ATiny4 i changed the LF357 with AD844 and results was great. Maybe why not and at DP?????

[giovan]

You need more more turns for a 33cm coil !!!!!!!
Calculate it for 800 ... 1000 uH

thanks

[Geo]

Hi Giovan.
You can use 32... 36 turns at a square 33cm coil
Regards

[dino]

Hello everybody, i wanted to ask you if anyone of you have a shematic for PI detector with PCB that can detect small pices of metal inside animal stomak since i have a problem with my pet. Its kinda wierd but if anyone have anything that can help it would be great. I need a small sonde detector.

Regards Dino

[kt315]

me and Delta Pulse at a lake.

[kt315]

.

[porkluvr]

Square coil calculator

Does anyone have a link to a coil calculator that can operate on rectangular coils?

[bbsailor]

Does anyone have a link to a coil calculator that can operate on rectangular coils?

Porkluvr,

Just multiply the square coil side length by 4 and divide that result by 3.14159 or pi to get the equivalent round coil and use the round coil formula. The results will be very close to the actual coil inductance.

Example: a square coil with a side of 10" (you can change the unit of measure to accomodate your coil) will have a total perimeter of 40". Divide 40 by 3.14159 and you get 12.732406" as the equivalent round coil diameter for a 10" square coil.

If your rectangular coil is narrow, use 2X the length plus 2X the width for the perimeter and the use the above method, When a round coil is squeezed into a oval with about a 1 to 3 ratio, the inductance will be reduced by about 10 percent from the round calculation. The same thing applies to a rectangular coil with a 1 to 3 length to width ratio.

I hope this answers your question.

bbsailor

[porkluvr]

Porkluvr,

Just multiply the square coil side length by 4 and divide that result by 3.14159 or pi to get the equivalent round coil and use the round coil formula. The results will be very close to the actual coil inductance.

bbsailor

That makes sense. Thanks, bbsailor.

[zenit52]

Hi kt315,

very nice picture from your Deltapulse,
please tell us your deltapulse, how much deep can detect
one 10*10 cm metal plate ?

Thanks...

[kt315]

hi zenit52. I tested DP only on pretty big Main Delay, 100 and more us. especcially for huge targets only. I did DP only as deeper on big targets, not interesting in small objects I can find out ordinary way. a sensitivity of DP was better than TF900. I use 1*1 metre coil. all targets that DP has found will be up on this week.

[aft_72005]

a sensitivity of DP was better than TF900

Hi KT315
yes, pi detectors working more stable than TR detectors at deep.
Best regards.

[aft_72005]

all targets that DP has found will be up on this week.

I waiting see it ………….