PICKINI V4 - an easy to build, self adjusting PI detector

[Goaty]

I have just finished preliminary testing of a waterproof detector housing using a standard Pickini board and all seems to be working well.





One question I have is in regard to the auto-tune function – Is it best to auto-tune with the coil in air or under water where it will be used?


Here are some pictures of my latest effort -






The Pickini seems ideal for underwater use as the sensitivity can be an internal pre-set pot and the only controls through the housing are the on/off switch and pinpoint switch. Switches are easier to waterproof using the rubber boots readily available online, provided a couple of steps are taken to make them more effectively sealed. These include locking in the threaded metal ring with CA glue and some extra sealing with silicone or urethane sealant.


Once I have had a chance to do more testing I will provide more info if anyone is interested. Hopefully no more leaks with this housing!

[SaltyDog]

Another PCB design that did not put the ICSP header on the board!

Yes, I feel that is a serious omission, maybe the next version?

[waltr]

On the PCB in the semi-kit, the connections for ICSP are not foreseen. You will need to hook up wires to an external connector that matches eg the Pickit3 programmer yourself.

Another PCB design that did not put the ICSP header on the board!

[BC547]

Look for "ICSP" = in circuit serial programming:
https://www.geotech1.com/forums/showthread.php?23400-PICKINI-V4-an-easy-to-build-self-adjusting-PI-detector&p=236925#post236925

https://www.geotech1.com/forums/showthread.php?23400-PICKINI-V4-an-easy-to-build-self-adjusting-PI-detector&p=245185#post245185

https://www.geotech1.com/forums/showthread.php?23400-PICKINI-V4-an-easy-to-build-self-adjusting-PI-detector&p=245429#post245429

On the PCB in the semi-kit, the connections for ICSP are not foreseen. You will need to hook up wires to an external connector that matches eg the Pickit3 programmer yourself.

[SaltyDog]

Hi Bernard,

Can the pic be programmed in situ? If so, please provide a diagram..

Cheers

[SaltyDog]

OK ... let's try attaching an image using Quick Reply:
[ATTACH]49658[/ATTACH]

Hmmm ... seems to work just fine.

Ok, I am using a Linux machine and the Pale Moon browser(Firefox compatible), maybe something to do with that combo? However, I am part of numerous forums, and never had an issue with any of them ... go figure ..

[Qiaozhi]

I only get that option when I go into Adanced editing mode, I have been using "Quick Reply". As far as I am concerned if you are not to use "Quick Reply" then it should be disabled, or the "Insert Image" button removed

If I go into advanced editing, then I get an "Attachments" pull-down. In there I see my two files that I have uploaded with question marks on them .... no idea what that means ... doesn't seem to be a way to delete them, so I can upload fresh ones ..

What is the story??? Why is this so hard ..

OK ... let's try attaching an image using Quick Reply:


Hmmm ... seems to work just fine.

[SaltyDog]

Try using Manage Attachments > Add Files > Done

I only get that option when I go into Adanced editing mode, I have been using "Quick Reply". As far as I am concerned if you are not to use "Quick Reply" then it should be disabled, or the "Insert Image" button removed

If I go into advanced editing, then I get an "Attachments" pull-down. In there I see my two files that I have uploaded with question marks on them .... no idea what that means ... doesn't seem to be a way to delete them, so I can upload fresh ones ..

What is the story??? Why is this so hard ..

[Qiaozhi]

Ok, but when I hit the "Insert Image" button, it prompts me for a file on my computer !!!! So what have i done wrong ? I am just doing what I am told ..

Try using Manage Attachments > Add Files > Done

[SaltyDog]

There's no problem with the forum. You must have attached it incorrectly.
Sometimes people add a link to a file that's on their personal computer, rather than uploading it in the correct manner. Then, of course, no-one else can see it except themselves. Another reason for attachments going AWOL, is when the link points to a file elsewhere on the internet, and that file has been deleted.

Ok, but when I hit the "Insert Image" button, it prompts me for a file on my computer !!!! So what have i done wrong ? I am just doing what I am told ..

[BC547]

Sounds normal .... chatter is typical when you switch on the detector inside the house.
Try to move it away from any EMI sources.

[bernte_one]

OK
1 is all right, Pinpoint works as it should

2 after start i get OK sound after 10sec or so, then the detector start to Chatter.
I can still detect but only very Close to coil.

Coil is 300microH Made from 0.6 Wire 19turn 35cm Dia, so nearly perfect

Earlier today i tried to adjust damping resistor.
I found out that 500r like basic Setup ist too low, at 620r the damping curve is smooother, but detection distance ist very bad.
I suppose the trouble are result od BC549 and LM318 (Offset, etc.)

[BC547]

You describe 2 different problems:
1/

how can i disbale mclr whule programming with mplab and pickit3?

If you have this problem, the controller should reset when you activate the pinpoint switch = MCLR low.
Then you should hear the welcome sound again.
As long as you don't push the pinpoint switch, this should not do anything, everything should start up and work normally.

2/ A problem with the DC offset of the opamp:
Pin 3 of the opamp is the DC offset that gets adjusted after startup.
Pin 5 of the opamp is not connected. The BS170 is not related to this. The BS170 is just a level converter that transforms the 5V pulses to 12V to the gate of the IRF740.

Do you get the coil error sound after calibration = continuous low tone ? This indicates that there are no flyback pulses at the input of the microcontroller.

I don't see a problem with the BC547: VBE = 0.6V.
But the collector voltage in your drawing is 6.15V. this should be equal to the voltage on pin 3 of the opamp, which is 8.3V in your case. In between the collector and the opamp pin 3 there are only 2x 10 ohm resistors in series = jumpers on the PCB.

[bernte_one]

or problem with bc549B?


ok i got some answer in
post 227 and 228
same problem

https://www.geotech1.com/forums/showthread.php?23400-PICKINI-V4-an-easy-to-build-self-adjusting-PI-detector&p=224290#post224290

how can i disbale mclr whule programming with mplab and pickit3?

[bernte_one]

i have no luck - some of the latest pickini i did last years will not work exactly
i got very similar problems on the 4 boards laying on my work bench
look the voltage diagram, pin 5 of lm318 has one very bad voltage can that be a result of bad bs170??

also pin 2,3, and 6 seems a bit off the tolerance

voltage from the pic controller looks also not ideal

Pic16F1824
Pin	normal from f117	my result with coil	without coil
1	5	5,02	5,02
2	2,7	3,18	3,18
3	1,2	2,76	2,76
4	5	5,02	5,02
5	4,7	4,7	4,7
6	0,1	0	0,3
7	0	0	0
8	3,7	4,22	4,38
9	3,7	4,21	4,38
10	2,7	3,17	3,17
11	0-5	2,5	5,02
12	2,8	2,75	2,73
13	2	1,52	1,52
14	0	0	0
LM318	normal from f117	my result with coil	without coil
1	9,5	9,25	9,17
2	6,8	8,3	8,23
3	6,8	8,3	8,26
4	0	0	0
5	4,8	9,28	9,2
6	7,4	8,4	8,82
7	11,9	11,76	11,76
8	1,4	1,3	1,32