IGSL

[Amalio]

Hello

miIGLS problems


when I connect the battery beep sounds for three seconds and then a constant instability.

I've tried up to 2.2 n C43 but in no way is left IGLS cancel

I new coils to lower the inductance

2.8 Ohms 0.976 Mh TX

RX MH 14.65 38.4 Ohms

As the frequency is 8.76 kHz TX, RX same frequency, measured at Rx output

I'm using dual coaxial video cable, which gives me a lot
conffianza

[Amalio]

More friends here with homemade coils IGLS musketeer to share experiences

regards

[ivconic]

Hello

miIGLS problems


when I connect the battery beep sounds for three seconds and then a constant instability.

I've tried up to 2.2 n C43 but in no way is left IGLS cancel

I new coils to lower the inductance

2.8 Ohms 0.976 Mh TX

RX MH 14.65 38.4 Ohms

As the frequency is 8.76 kHz TX, RX same frequency, measured at Rx output

I'm using dual coaxial video cable, which gives me a lot
conffianza

Amalio,
C4 + C43 (in parallel) = 15nF (in range 14.7nF to 15.5nF approx.)
...

[Amalio]

Hello

I tried to C43 Ivconic values y2n2 4N7 2N7 3n3, accompanied by C4 10n, despite this IGLS not operate in conditions of cancellation

aluminum foil coils isolated

I have doubts with double coaxial video cable, I will seek to replace Belden

thanks

[ivconic]

Hello

I tried to C43 Ivconic values y2n2 4N7 2N7 3n3, accompanied by C4 10n, despite this IGLS not operate in conditions of cancellation

aluminum foil coils isolated

I have doubts with double coaxial video cable, I will seek to replace Belden

thanks

Could be, but i would rather suspect coil balance.
But yes, you are right; first replace cable with more proper one, than try to achieve better balance.

[Wiltran]

Caps

Ivconic, if you remember from one of my earlier posts, I couldnt get IGSL to work, I put in wrong caps C17,C23, C30, C36 I used 4.7 NF. and it was a failure. I replaced with 1 MFD box film caps, and it worked good. Would the 1 mfd caps affect the performance negatively? I know they should be .47 MFD.

[ivconic]

Ivconic, if you remember from one of my earlier posts, I couldnt get IGSL to work, I put in wrong caps C17,C23, C30, C36 I used 4.7 NF. and it was a failure. I replaced with 1 MFD box film caps, and it worked good. Would the 1 mfd caps affect the performance negatively? I know they should be .47 MFD.

Not significantly.
At least will not cause problems similar to what you are facing now.

[Wiltran]

Not significantly.
At least will not cause problems similar to what you are facing now.

Do you mean the problems I was facing when I originally put in 4.7 NF caps?

[ivconic]

Do you mean the problems I was facing when I originally put in 4.7 NF caps?

No, i mean your problems are not caused by 1uF caps but from something else.
Like i said; must be the coil ...

[Wiltran]

No, i mean your problems are not caused by 1uF caps but from something else.
Like i said; must be the coil ...

Ok, I am working on the coils for better operation. By the way thanks for the good metals discrimination chart, its very helpful in understanding the phase differences in coins vs. ferrous, foils ETC. This is a good lead in to understanding VDI setup and operation!

[ivconic]

Ok, I am working on the coils for better operation. By the way thanks for the good metals discrimination chart, its very helpful in understanding the phase differences in coins vs. ferrous, foils ETC. This is a good lead in to understanding VDI setup and operation!

Thanks to White's, i ripped it out from their .pdf and added my sketches...

[habitbraker]

Dear Habitbraker,

I have read TGSL forum several times (really interesting, enjoyed it and learnt a lot), I have also read Don Bower's excellent TGSL 101, parts I & II at least 4 times and used it even to build my coils (really good information).

I am sure that for anybody who has made and used a TGSL you are 110% correct, then the IGSL is easy. But for an electronics Engineer that has spent the last 40 odd years working only in "DIGITAL" electronics, who has not ever built a TGSL machine, its not quite so "cut & dried" as you obviously feel it is.....

Of course I know the building blocks, but I still don't understand the way it all hangs together in the manner that I wish to.

Some of the names elude me completely (does GEB mean "Ground Exclusion Balance? If yes, what does THAT mean????), even though I have built several IB machines over the last 30 years.....nowhere near as complex though as the IGSL.

You are sitting on the other side of the fence from me with your TGSL and IGSL knowledge, for you it is easy....try and be a little more understanding of the situation.....

The last time I was "immersed" in analogue electronics, it was all Tubes/Valves and I was setting up twin 4.5" gun turrets and Sonar equipment in the Royal Navy......(helps a lot with setting up an IGSL!!!)

By the way, you may be a useful Guy to know later, if you have actually built an IGSL, if I need any fine tuning for mine, is that OK with you?

By the way, have you actually built, tuned and used an IGSL? Or do you only have TGSL experience?

Thanks in advance for your help with my IGSL and have a great day anyway......

Andy

http://www.geotech1.com/forums/showp...&postcount=110

Working like charm

[ivconic]

http://www.geotech1.com/forums/showp...&postcount=110

Working like charm

Of course it does!
If all is made properly - than it must work good.

[der_fisherman]

Problems getting my IGSL, DIY Coils PCB to work

Hi All,

I need a bit of help as I cannot get my IGSL to do anything like making a noise at all!

The -6.2 volts and the 8 volts are found on all chip sockets at the correct points.

There is about 8 volts sine wave on the Tx coil.

The problem appears to be around the 4066, I have replaced it 3 times with no change.

The output of U1a from pin 1 can be seen on the scope at U11 on pins 1, 3, 8 and 10.

There are also signals on the 4066 Pins 13, 5, 6 and 12 from U4d pin 13, U4c pin 14, U4b pin 1, U4a pin 2 .

But I see only a (slightly) changing DC level on the 4066 pins 2, 4, 9 & 11 when turning the related pots or trimmers, where I would expect to see some part of the input signal, modified by the ON/OFF signal on the 4066 output pins.....

I suspected the 220 nF Caps and removed C39, but it tests out perfectly, I am loath to remove the others just for testing. I had hoped that there was a short to ground there....

If I lift the pins 11, 9, 4 & 2 of U11 out, I can see signals being output on them using the scope, though they may be of very high impedance and I am just picking them up "across" the gate....

I have cleaned the PCB again of any flux residue and gone over the pcb with a high powered magnifying glass looking for shorts, breaks and dry joints. I may have to get the soldering iron hot again and touch each one to be sure.

I have set the coils at both a good null and offset to around 10mVolts to no effect.

I have also reversed one coil just in case.

All to no effect. Still no "signals" from out of the 4066 when connected correctly.

My next idea is to replace some of the Diodes as measuring them in circuit may not be quite good enough, though there is a difference depending upon the polarity of the meter leads that suggests the diodes are OK.

The strange part is that I have also replaced every single chip as least once on the PCB.

Also that all 4 signals FROM the 4066 are affected.....The version I am using is the HCF4066BEY that appears to have a sightly increased voltage range as the main difference.....but the problems have been the same from all the parts I have had, including the 4066 from SilverDog....

Thanks for any help and regards from

Andy

[porkluvr]

Hi All,


... till no "signals" from out of the 4066 when connected correctly.


Thanks for any help and regards from

Andy

Are the square waves driving the 4066 being pulled to ground, or do they swing to +8V?

The JFETs in the TGSL were pulled to ground but those 4066 switch control signals should be pulled to +8V. Is there a possibly a routing error?