My Surf PI works - thanks Silverdog and ApBerg

[ant]

Hi Everyone

Sorry if this thread is in the wrong place, mods feel free to move.

I ordered a couple of kits from Silverdog a few weeks ago, they finally arrived yesterday (slow post to Aus).

Soldered the board up last night over a few beers, hooked up the coil (thanks for the instructions ApBerg and Qiaozhi for the calculator) and power supply but only got beeping no matter how much I fiddled with the pots . Decided it was time to go inside have more beers and think where I might have gone wrong.

Coming home from work today, straight back to the shed, noticed I'd left the two wire joins off the board, soldered them in and woohoo it worked.

Thanks Silverdog for the excellent kits.

Thanks ApBerg for the design (I think it was yours) and the coil help.

Thanks Qiaozhi for the coil calculator.


Ant.

[WM6]

Coming home from work today, straight back to the shed, noticed I'd left the two wire joins off the board, soldered them in and woohoo it worked.

Congratulations ant. Wish you full success in field.

P.S.: You use unusual PCB fixture - what about shorts?

[ant]

hehe

powered off for the photo

[ApBerg]

Hello Ant,

Nice you have it working. And yes I made the pcb design, but the real genius was Mr. Lahr the inventor and of course White's that make's the real Surfmaster.

Have succes with it !

Ap

[goldfinder]

What kind of depth?

Great Job - success is wonderful ! Would you mind measuring air detection distance on some know coins like a quarter, dime, and penny to give some idea of the sensitivity.

Goldfinder

[ant]

Hi GoldFinder

This is my first built MD, so I'm trying to get my head around the circuit and how it actually works. At the moment it's not great, but that might be because I'm testing it in a steel shed, with reinforced concrete floor, a steel workbench and pretty much a bunch of steel around me. So yes I will test the distances, but it might be a week or two before I can get it out of the shed in a working form. BTW, I'll have to use Australian coins, but should get an idea.

Thanks everyone.

PS. Just on the point of trying to understand how it works, is it recommended to build one of the Hammerhead varieties? (I think I just answered my own question)

[WM6]

PS. Just on the point of trying to understand how it works, is it recommended to build one of the Hammerhead varieties? (I think I just answered my own question)

HH is best PI learning platform because of many controls it offer, bur Surf PI as first step cannot be wrong decision.

[ApBerg]

Hi GoldFinder

This is my first built MD, so I'm trying to get my head around the circuit and how it actually works. At the moment it's not great, but that might be because I'm testing it in a steel shed, with reinforced concrete floor, a steel workbench and pretty much a bunch of steel around me. So yes I will test the distances, but it might be a week or two before I can get it out of the shed in a working form. BTW, I'll have to use Australian coins, but should get an idea.

Thanks everyone.

PS. Just on the point of trying to understand how it works, is it recommended to build one of the Hammerhead varieties? (I think I just answered my own question)

Hello Ant,

Start with all the potentiometers in mid position, then tune the threshold/tune potentiometer at the point that you get some sound, tray if you can get some detection for a solid gold ring. If so adjust the delay potentiometer to the point that this ring is detected at the best distance . If you turn to far there is suddenly no detection anymore, no harm is done just turn back again to the best point you had.
The offset potentiometer is a problem if you have not a scope. But... if you have a good detection for a gold ring then swing the ring fast from left to right and right to left over the coil and listen to the sound, adjust the offset potentiometer so that the sound response in both directions is the same, tray this with different speeds. Let us know if you can use this setup ?
If somebody has a better way...

A solid gold ring must be detected at some 23- 25 cm (some more if a good coil is used)

Succes

Ap

[plumabob]

Waiting for mine to arrive. Great job! Hope mine works out as well!

Bob

[ant]

I do have a scope

Hi ApBerg

I do actually have a scope, and was going to go thru the circuit diagram to see what I should be looking at with it. Just so you know, I am a novice with electronics but I do want to understand how it works. Just to get me started, where would I hook the scope up?

Thanks, Ant

[Rov]

think if you look at your pcb you will see some pads there with TP or test points these are for your scope or meter to check from.at relevant stages of the circuit.
connect your scope probe to these,an ground connection also.
What the wave forms an signal properties an values are Im not sure.
The creator of this PCB design can supply you with these an what you should be seeing.
I havent built this unit yet so I cant tell you difinitively myself.

[Micheal]

I have an original SURF Pi coil that I have opened up for experimental purposes ....im not sure if I am allowed to post pictures of it as it is an original whites coil ....If carl okays it I can post them here ...
just trying to help all the Surf pi builders

[ant]

Rov; Thanks for the tips, I briefly hooked the scope up to TP1 and TP2, changed the pots and saw the scope change, but I think I need to understand the circuit before I can understand what I see on the scope. I'll do a bit more study over the weekend.

Micheal; That would be great if Carl approves, can you PM me a pic in the meantime, I'm thinking I should try another coil for experimenting.

Plumabob; Thanks, hope all goes well with yours.

Apberg; Thanks for the tips, good to know where I need to start. I tried to change the threshold/tune potentiometer but can't get it to give a constant buzz, I really need to study the circuit.

Thanks everyone

[ApBerg]

Hello Ant,

Have you made the small jumper (link wire) connecting the 4066 to MPSA13 ?
you find this link on top R16

Succes

Ap

[Rov]

Hi Congratulations on this Fine design,Hope it works well for all builders of this revised design.
ApBerg,Are there other Notes an Errata that builders should be aware of for a successful build?
eg.other wire links,as there appears other unused pads on the pcb.or a substitution of parts.eg.2n3906 can use BC327 or changing 1n4004 diode to Fast recover Diode etc.
I notice on some pictures here on the forums from recent past ,extra Capacitor at position C16 on pcb.being a .1 MKT style and extra GreenCap Poly with unknown value beside it.??
I havent built this unit yet myself,waiting on parts?So would wish that my parts list as other builder,is true an complete?
Thank You,
Rov