IGSL

[Gwil]

-6.2volt appropriate arrangement

Generating a regulated -6.2V from the +12V supply looks like a good idea, but I think there are a couple of problems with the schematic as shown -

(1) C11 needs to be at the input of the regulator to smooth out the current pulses from the charge pump. (Small capacitors may also be needed at the input and output for stability.)

(2) U2 pin 12 swings between 0V and +8V. This turns Q4 on and off, but with the emitter of Q3 at +12V, Q3 will never turn off. At least that's how it looks to me. An additional level shifting stage would take care of this.

Any comments?

Gwil

[mikebg]

A lot of Chinese goods also have a CE mark, but the C and E are too close together. Some claim that it stands for China Export.
Perhaps you should change it to either SE or IE.

http://en.wikipedia.org/wiki/CE_mark

[Qiaozhi]

http://en.wikipedia.org/wiki/CE_mark

Exactly my point.
But perhaps Ivconic could use SE (Serbia Export) or IE (Ivconic Export).

[simonbaker]

Generating a regulated -6.2V from the +12V supply looks like a good idea, but I think there are a couple of problems with the schematic as shown -

(1) C11 needs to be at the input of the regulator to smooth out the current pulses from the charge pump. (Small capacitors may also be needed at the input and output for stability.)

(2) U2 pin 12 swings between 0V and +8V. This turns Q4 on and off, but with the emitter of Q3 at +12V, Q3 will never turn off. At least that's how it looks to me. An additional level shifting stage would take care of this.

Any comments?

Gwil

I had similar questions too. Maybe U2 should work off +12V as well. I probably would have put C11 at input too; wouldn't have thought of putting it at output only, but maybe works fine. Also agree I would like capacitors at both input and output, but how many parts can we add to this PCB!

TGSL/IGSL may in fact be quite immune to ripple in phase with TX oscillator, so need to test if makes any difference anyway.


-SB

[der_fisherman]

I have to report that my method of making fairly flat coils did not work. The super glue I used simply did not hold. So I am making "Jumbled" coils (normal ones) for now.

[simonbaker]

I have to report that my method of making fairly flat coils did not work. The super glue I used simply did not hold. So I am making "Jumbled" coils (normal ones) for now.

I could see they might be delicate. I use the dfbowers "glue pot coating" method which drags the wire through a varnish as it is wound. It makes a pretty tough bundle that might survive flatness if you let it dry sufficiently. The hard part is trying to keep it from sticking to the form. Maybe there is a way to lay paper on each side of the form, and just let the paper stick to the coil and provide support (cut away excess later).

-SB

[SVEN1]

I have tried several times to bend aluminum tubing to make S-Rod for detector. No luck at all. I have tried several methods and just have not been able to do it without kinks or cracks. This would be an excellent subject for a thread if someone has the knowledge. It certainly isn't me.

Jerry

I have bent some smaller dia aluminum tubing in the past by heating the area up with a propane torch. It does work without kinking or cracking

[der_fisherman]

I could see they might be delicate. I use the dfbowers "glue pot coating" method which drags the wire through a varnish as it is wound. It makes a pretty tough bundle that might survive flatness if you let it dry sufficiently. The hard part is trying to keep it from sticking to the form. Maybe there is a way to lay paper on each side of the form, and just let the paper stick to the coil and provide support (cut away excess later).

-SB

I have a few ideas for the next search head, but I want to get my detector going asap for the moment!!

[Dukeshooter]

Shaft Bending

In my experience aluminum bends better after annealing it.
I have not tried a detector shaft, but I have had success bending aluminum.
I use Oxy-Acetylene with almost no oxygen and get the metal all sooty.
A propane or butane torch should work though.

[Wiltran]

bending alum

OK Sven and Dukeshooter HMM... interesting propane, acetalene low heat, OK Ill experiment.. next step TIG welding angles. one way or another

[Dennis the Mennis]

I have tried several times to bend aluminum tubing to make S-Rod for detector. No luck at all. I have tried several methods and just have not been able to do it without kinks or cracks. This would be an excellent subject for a thread if someone has the knowledge. It certainly isn't me.

Jerry

Allthough I never tried bending Al how about this ?
Overhere you can rent them at allmost every D.I.Y. store or hardware store ...
I certainly works for copper , or (don't know the exact name : the pipe used in houses for heating ; heating pipe ) as long you've got the bending tool for the right diameter .

Or a combination of heating / spring inside with the bending tool ?
Like the tool seen in the clip Ivconic sended.

kind regards

Dennis the Mennis

[ivconic]

Just received pcb's form Silverdog...WOW!
Top quality!
It is joy to make detector on such pcb!
Splendid job again Silverdog!

[der_fisherman]

SilverDog Kits

Just received pcb's form Silverdog...WOW!
Top quality!
It is joy to make detector on such pcb!
Splendid job again Silverdog!

Feverishly waiting on mine too.....

regards

Andy

[ivconic]

Looking at these, for real top notch pcb's... i am starting to think that maybe is not bad idea to transfer IGSL to SMT... later, maybe in Winter...
Because, i refused to think on SMT so far, simply because i hadn't conditions to get such hi pro pcb's!
But now.. different story..!
So.. till winter i will do my best to upgrade ISG project a bit more.
I don't have any finished idea by now (don't suspect in that der fisherman! ).. but will do my best to have something till winter...
So than we will talk about SMT...
I am so so skilled with SL5 when conventional, through hole pcb's are subject, but i am not skilled at all with SMT.
So if someone of you have good will to transfer it in SMT - be my guest!
Or, better wait winter to get updated IGSL than.
Silverdog with his splendid work will change my attitude and point of view toward hobby electronics!

[der_fisherman]

New SMT(?) IGSL thoughts by Ivconic

Looking at these, for real top notch pcb's... i am starting to think that maybe is not bad idea to transfer IGSL to SMT... later, maybe in Winter...
Because, i refused to think on SMT so far, simply because i hadn't conditions to get such hi pro pcb's!
But now.. different story..!
So.. till winter i will do my best to upgrade ISG project a bit more.
I don't have any finished idea by now (don't suspect in that der fisherman! ).. but will do my best to have something till winter...
So than we will talk about SMT...
I am so so skilled with SL5 when conventional, through hole pcb's are subject, but i am not skilled at all with SMT.
So if someone of you have good will to transfer it in SMT - be my guest!
Or, better wait winter to get updated IGSL than.
Silverdog with his splendid work will change my attitude and point of view toward hobby electronics!

I haven't done any SMT (do you mean SMD? Surface mounted Devices!), but I do have Eagle 5.4 which can do SMD.

Also KICAD which is completely free can do it to I am very sure.

The secret is that both have extensive libraries of components, its unlikely that you must design a new component, but still possible if you do.

I am putting this a bit simply, but all you need is a finished schematic and apply SMD devices to it instead of conventional ones and then tell Eagle to make a PCB......(it is more complicated than that, but I hope you get the idea!).

I would be willing to help as well....though I must learn SMD as well.....

Regards

Andy