Blind Squirrel PI good easy design

[Alexismex]

Thank to Mike Starcher for this easy and good design , i make it and it give me good result for the time i experiment because of the design Of SINGLE POWER SUPPLY you do not have 7660 etc,,, no supply problems !!! see it

http://oldradiobuilder.com/MDET.html

I recommend for beginner because with this smart circuit you will understand easily PI Theory ...the function of TX width pulse, The frequency of the pulse, the Delay and RX width pulse .... just fine to make....and experiment...
my only change was :
C9= 2200 uF 25V Tank energy for the pulse transmit
C5=.022 for longer tx width adjust
U5= TLC272 work fine from MOUSER
OC1=4N25 I use this because i do not have 4N35 ... work fine.
My first working frequency was 109 Hz and later I choose 873 Hz for better time response ....

The result performance is good in sensibility
Aluminum coke to 80cm with 44cm coil -380 uH-17W-1.5R
Improvement to make in future is in the threshold adjustment and audio punch!!!!
Thank's again to Mike
Alexis.

[Alexismex]

MORE photos...
pulse1 -TP3-50uS and 5V amp.
pulse2 -transmit 100us -TP1- esc 20uS and 2V amp
pulse4 -TP2- RX sample 18 uS
pulse5 -TP3-20us and 2 V amp.

[Kos]

Delta!

Delta Pulse is a better choice for beginners, the Blind PI doesn't have secondary sample...

[WesP]

Delta Pluse

I have read many post about the Delta Pulse but where is the build information? I don't find it on Geotech.

[Alexismex]

Hello forum,
Not so easy for the delta pulse , just to see the schematic
Alexis

[ivconic]

I really do not remember exact number of Delta Pulses i made so far. Might be over 20. Also i made 2 Blind Sw.'s.
Yes this one is much simplier and do not have total control on signal as Delta Pulse. Yet, it is simple,small and very nice design! I do recommend everyone to make it. I liked it from the start.
It is very nice cose it is small and can be packed in small enclosure and used on the field with some "older brother".
It has very descent depth.
I can only pay tribute to its designer and thank on his good will to post full project here,on this forum.
Regards!

[ivconic]

I have read many post about the Delta Pulse but where is the build information? I don't find it on Geotech.

Hm, you have here all explained..
https://www.geotech1.com/thuntings/s...ead.php?t=8003

What else do you need?

[miki73]

Do you use shilding for this coil?

[Davor]

Now that I'm aware of this project, I must say it is just about the thing I hoped to see done already. And here it is. A real chopper and a SAH, followed by an integrator, just brilliant. Kudos!

I intend to play with it and I might add some modifications to it in due course. With a project as straightforward as this one it shouldn't be too difficult. Maybe some kind of motion compensation...

Thanks.

[Brian Deese]

Hello forum,
Not so easy for the delta pulse , just to see the schematic
Alexis

How do you make your pc boards Alexis?

[Alexismex]

Hello Brian . i made this board with hand drawing (conventional mode) because it is a easy schematic and next with perchlorate

[Brian Deese]

Hello Brian . i made this board with hand drawing (conventional mode) because it is a easy schematic and next with perchlorate

I was talking to Mike,he was explaining to me about the pcb making process.I have never done it so I have no knowledge of it.So you can draw the traces with a marker and then etch and thats all it takes? Just a marker?

[6666]

Brian its an easy process
what works for me is get a photo copy of your pcb tracks,
lay it on a clean piece of copper pcb,
next lightly punch all the component holes through the paper,
then with a Etch Resistant Pen, connect the dots to make the tracks,
then into hot perchlorate bath, when etched clean off the resist and drill the holes.
Crude but it works.

Some people have found certain brands of marker pens will work
but all the marker pens I have tried the ink comes off in the hot etchant bath.

http://www.jaycar.com.au/productView.asp?ID=TM3000

[Midas]

Brian its an easy process
what works for me is get a photo copy of your pcb tracks,
lay it on a clean piece of copper pcb,
next lightly punch all the component holes through the paper,
then with a Etch Resistant Pen, connect the dots to make the tracks,
then into hot perchlorate bath, when etched clean off the resist and drill the holes.
Crude but it works.

Some people have found certain brands of marker pens will work
but all the marker pens I have tried the ink comes off in the hot etchant bath.

http://www.jaycar.com.au/productView.asp?ID=TM3000

Yeah just the standard black Artline permanent marker has worked well for me, IMO just as well as the 'special' pen from Jaycar. Its a quite a bit cheaper, lasts longer, and you can get it almost anywhere.

Midas

[6666]

Hi Midas when you draw your lines do you over write them ?
and what number is on your standard black Artline permanent marker
is it 70 or 17 or what ?
what country are you in if you dont mind ?
thanks
6666