My Surf PI works - thanks Silverdog and ApBerg

[Guzzi]

http://www.md4u.ru/viewtopic.php?f=41&t=268&start=25

Try this, with CHROME this will be translated.

Regards

Leendert

[jcarmony]

Hey all! I purchased this PI kit from Silverdog (and its an excellent kit BTW) and completed it without much trouble. I used a 390ohm damping resistor with a 24awg 9" coil wrapped 18 times @ 2.1ohms unk inductance (I had originally used 24 times but had to use less windings see below). I get about 5-6 inches from US quarter about same with small gold ring. About 20" on an old tin can. I have been trying to tweak this as much as possible (only for instructional purposes). I have read many posts on the Surf PI tweaking coil making ect and came across this one with photos of the surf under a scope. I finally got the delay set as close as I can (I had to make smaller/less wound coil) see below, this is on PIN 3.



According to the previous post with the scope pictures I understood it PIN 3 and 4 on the 4093 are the same, however PIN4 on my 4093 is much different:



Also, although I have read many forum post about the Surf PI, does any one recall off the top of thier head any posts that contains more oscope tuning for the Surf PI? Many thanks !!!!

[drinnird]

just ordered my kits, looking forward to joining you all who have successfully built this project! Ill try to write up a guide to build and tune this kit while im building it for those who are still debating on it

[Davor]

It is acid based, so try not to forget washing your boards prior to abandoning them for a long time.

[ApBerg]

Depending on Humidity, Solder Flux adds Resistance between Traces.
And this Flux will be on BOTH SIDES of the board as It goes through the Holes when Soldering.

I use a Kester 331 Solder. It is a Tin/Lead solder and it contains a Water Based Flux.
So to clean the board you just put it under a Warm Water Tap and rince it off good on BOTH Sides.

I wash my boards with ALL IC's and Trimpots on the board, than DRY it Good, before applying Power. (MOST parts are OK with Water)

Never new that there is water based flux... works it the same as 'normal' solder ?
Thanks for the info !

Just read on the WWW that there is also less smoke ?

[ApBerg]

So I am looking to remove the oil from my hands,and the hard glass like flux from around the solder joints? And alcohol will dissolve the flux? I have heard of washing boards in warm water also?What does the flux add capacitance between pins?

Well.. removing the flux from the board has the advantice that you can check your solder work better. Looking for 'solderbrige's' or bad joints is with a clean board much easier !


For low freq's I think that it is not so important that there is some flux on the board... ?
Think that the use from IC sockets ads more capacitance then some flux between the pins ? .... well let the real experts shoot on it....

Best regards

Ap

[chemelec]

So I am looking to remove the oil from my hands,and the hard glass like flux from around the solder joints? And alcohol will dissolve the flux? I have heard of washing boards in warm water also?What does the flux add capacitance between pins?

Depending on Humidity, Solder Flux adds Resistance between Traces.
And this Flux will be on BOTH SIDES of the board as It goes through the Holes when Soldering.

I use a Kester 331 Solder. It is a Tin/Lead solder and it contains a Water Based Flux.
So to clean the board you just put it under a Warm Water Tap and rince it off good on BOTH Sides.

I wash my boards with ALL IC's and Trimpots on the board, than DRY it Good, before applying Power. (MOST parts are OK with Water)

[Brian Deese]

Hello Brain and other friends,

What I do is as follows...

Take a old toothbrush dip it in a bottle with Isoproponol alcohol, so that there is lots alcohol on the brush. Brush this over the copper side from the pcb.
If this is done take a sheet kitchen cleaning paper and put this over the sill wet pcb.
Now brush over the kitchen paper so that it picks up the dirty alcohol that is on the pcb. If not clean the first time than repeat this again. Watch for clean teeth between the ic's
I always do a last time cleaning without the paper.. so I can see it is really clean.

Regards.

Ap

So I am looking to remove the oil from my hands,and the hard glass like flux from around the solder joints? And alcohol will dissolve the flux? I have heard of washing boards in warm water also?What does the flux add capacitance between pins?

[Davor]

Some 20 years ago we used canned freon to do that, and it worked miracles. Just spray it liberally and watch it bubbling dirt away. Too bad it is ruining atmosphere.

[ApBerg]

I also think that building the board and leaving the trimmers off until LAST allows you to soak the board in CLEAN isopropyl alcohol for half an hour or so to remove ALL contaminants, then coating the board with conformal sealer goes a LONG way to making the Surfmaster a LOT more sensitive.
Quote from Sean Goddard:

Is that only if the board is socketed? You cant put an IC under alcohol can you? I need to clean mine,it has low sens also,and the solder side looks dirty where I have handled it.I can only get about 4" on a us quarter.That has to be corrected.

Hello Brain and other friends,

What I do is as follows...

Take a old toothbrush dip it in a bottle with Isoproponol alcohol, so that there is lots alcohol on the brush. Brush this over the copper side from the pcb.
If this is done take a sheet kitchen cleaning paper and put this over the sill wet pcb.
Now brush over the kitchen paper so that it picks up the dirty alcohol that is on the pcb. If not clean the first time than repeat this again. Watch for clean teeth between the ic's
I always do a last time cleaning without the paper.. so I can see it is really clean.

Regards.

Ap

[Brian Deese]

I also think that building the board and leaving the trimmers off until LAST allows you to soak the board in CLEAN isopropyl alcohol for half an hour or so to remove ALL contaminants, then coating the board with conformal sealer goes a LONG way to making the Surfmaster a LOT more sensitive.
Quote from Sean Goddard:

Is that only if the board is socketed? You cant put an IC under alcohol can you? I need to clean mine,it has low sens also,and the solder side looks dirty where I have handled it.I can only get about 4" on a us quarter.That has to be corrected.

[maxfly]

Thanks 6666,

I have checked that out already, but will double check again.
My tune pot works fine, just no response from delay pot!!

[6666]

Maxfly "Remember to check your R18 and R22 are in the right position - as typo on the silk screen." gives low sens if wrong

Use details to improve depth as in the link

http://www.geotech1.com/forums/showthread.php?t=18445

[maxfly]

Hi all,

I have just completed my Surf PI board and have been testing it.
I also have low sensitivity, probably due to the fact that I can't get any response when adjusting the delay pot (makes no difference across whole range of adjustment). Pot tests okay, are there some simple test I can do with a multimeter to eliminate causes?

[Sean_Goddard]

Anyone thought if using an IGBT for this application?