IGSL

[der_fisherman]

Updated Schematic for IGSL with TGSL Coils

I have made a minor update of Ivconic's IGSL for TGSL coils and added the way the pots should be connected.

Please note the following:-

CW = Clockwise (im Uhrzeigersinn)
CCW = Anticlockwise.
W = Wiper or center contact. ( The "W" is not easy to see without making the schematic larger in some cases).

I have also changed the values of C16, C24, C29 & C37 from 103 to 22nF as suggested by Ivconic I believe.

Also the values of R31, R45, R50 and R64 from 1M5 to 470K have been changed for the same reason.

The same PCB will work with either the old or the new values, so no real reason to change that, even part numbering remains the same. Naturally the parts list is slightly different that you can print out from ExpressCSH.

Please check the schematic out fully and I would appreciate if any errors you find are reported back to me as soon as possible so that I can update the schematic further, thanks for your help.

(These additions are probably good for the IGSL with a Musketeer Coil as well, but I do not guarantee that personally).

Regards

andy

[simonbaker]

I have made a minor update of Ivconic's IGSL for TGSL coils and added the way the pots should be connected.

Please note the following:-

CW = Clockwise (im Uhrzeigersinn)
CCW = Anticlockwise.
W = Wiper or center contact. ( The "W" is not easy to see without making the schematic larger in some cases).

I have also changed the values of C16, C24, C29 & C37 from 103 to 22nF as suggested by Ivconic I believe.

Also the values of R31, R45, R50 and R64 from 1M5 to 470K have been changed for the same reason.

The same PCB will work with either the old or the new values, so no real reason to change that, even part numbering remains the same. Naturally the parts list is slightly different that you can print out from ExpressCSH.

Please check the schematic out fully and I would appreciate if any errors you find are reported back to me as soon as possible so that I can update the schematic further, thanks for your help.

(These additions are probably good for the IGSL with a Musketeer Coil as well, but I do not guarantee that personally).

Regards

andy

Thanks for the good work and persistence.

-SB

[detecto]

IGSL PCB with values



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[detecto]

Its nice for checking component values.
Regards

[satdaveuk]

Very handy for double checking component values when required, although I prefer circuit ref numbers to work along side the circuit diagram as manufactures do otherwise your working blind.
Many thanks for the input to this project

Regards

[der_fisherman]

Uploaded with ImageShack.us

Nice one, well done and thanks.

regards
andy

[der_fisherman]

Uploaded with ImageShack.us

It does not seem to be at the latest levels of component.....

Can someone let me know if I am right please? I checked R45 and it is still at 1M5, not 470K as it should be!!

This is a TGSL Coil version it should also be noted.

Regards
Andy

[kliner]

corrections on IGSL

It seems that C15, C25, C28 C38 A and B have not been changed either.
These were changed on the TGSL because 4.7mf non polarised are required, if you put 2 4.7mf series it's non polarised but it gives you 4.7/2 = 2.3mf I think it was Ivconic who remarked that they should be 10mf each. (10/2 = 5mf close enough)

[detecto]

Component update

I used Silver dogs's part list. Also i made IGSL exactly like i posted, with that values and it don't work at all, i reversed Q2 pins and probably burned CD4024. Ill replace all chips tomorow and see what is going on...
Regards

[der_fisherman]

I used Silver dogs's part list. Also i made IGSL exactly like i posted, with that values and it don't work at all, i reversed Q2 pins and probably burned CD4024. Ill replace all chips tomorow and see what is going on...
Regards

It will work with the old values of caps and resistors, but not as well as it could - sadly...

I have replaced all of the said caps and resistors and though I am not yet fully happy, it is working much better.

My main problem is that there is not a "setup procedure" available with Scope pictures anywhere from any of the IGSL experts......that is killing me!

Don B. made a great double .pdf file for the TGSL with everything brilliantly written out with pictures etc.. Well worth a read even if you are not building a TGSL!!!

I may decide to make an Eduardo TGSL soon to help me get better aquainted (an IGSL is more or less a TGSL x 2 I am reliably informed!)

Regards

Andy

[satdaveuk]

Component ID and construction

The problems with putting component values on PCBs is that there only as good as the day they were produced and with the nature of Geotech which basicaly is a design and improvements forum which means that modifications are coming in almost everyday so its very important to make these projects along side the latest circuit diagrams together with previous versions to compare changes, to the version of board your baseing your project on.
That is why my prefered option is circuit part numbers so its easer to work between the two
Also very important keep track of imformation thats been placed in the forum of your project because pitfalls etc are a regular feature.

Im still very much doing modifications to the TGSL project and that started way before this project and still ongoing, and if I had put on component ids instead of circuit reference numbers it would have been very inacurate.
Always assemble/faultfind with circuit diagram to your left alongside PCB layout and work between the two double checking, any alterations/mods that are presented on the forum write down notes, I normally end up with a big folder due to the good people on here working hard to improve what is already a good project.
If anyone thinks for one minute they can pick up a PCB and just mount components as indicated on that PCB and its goint to work on switch on, then in my opinion there in for a suprise unless there very lucky.
As ive stated on here before the projects on these forums are not a finished items they are ongoing and and proberly still will be when alot of us here will be pushing up daisys.
And so be it thats what Geotech is all about great minds clever engineers always going for that extra yard to makes detectors work better.
Warm regards
Dave

[golfnut]

I made my IGSL from the parts list and the silkscreen from silverdog website.

I had no blown parts and my detector works.


I did not need a scope.

Steve

[kliner]

My IGSL worked (coil minlab TS1000) as per Silverdog's kit as well but I did notice an improvement after the above mentioned changes, I earthed the earthy side of the RX coil as well, it seems to help. Mine can detect a 1 euro piece at about 30 centimetres in air. My problem is that I cant ground balance out a small piece of ferrite on either channel.I am going to start on another one to see if there is any difference.

[golfnut]

Sounds like a build error.

If not,


try slightly bigger cap on the geb RC phase shifter..


either pull the 100pF and try 180pF.

or add a 68pF across existing 100pF.


I run my Tx osc off the 12v rail for a little more Tx signal, and I ran out of GEB adjustment on the ferrous CH as a result.

Put a little more C' in and back the R off a bit.

Steve

[kliner]

Thanks Golfnut, that seems to have helped a lot. With 180 pf on each GB channel I can ground balance to nearly completely eliminate the ferrite, not as good as the TGSL but I think is should be ok. Time to try it outside now.
Thanks again