TESORO GOLDEN SABRE

[08llyj]

SILVERDOG KIT

HI DFBOWERS,THX FOR YOUR QUICK ANSWER
VERY GOOD JOB
AND NOW THE TEST OF THE COIL
THX FOR ALL

[dfbowers]

hi
i want to bye the tgsl kit of silverdog but is it ok.
work t 'il correctly .
thx for all your jobs,pics,pcb,.....

Kit is perfect. You should not have any problems with what Silverdog can supply.
The coils will be the likely challenge.

Don

[08llyj]

tgsl kit

hi
i want to bye the tgsl kit of silverdog but is it ok.
work t 'il correctly .
thx for all your jobs,pics,pcb,.....

[silverdog]

Some great work by Don and others, most beyond me at the moment, but I'm trying to understand it - looking forward to the troubleshooting section, thats the one I always use most

My contribution is to recycle some recent sales money - I have for the rest of June reduced pcbs by 50% and kits are reduced to just £21 GBP

Silverdog

[dfbowers]

Side note:

I notice on eduardo's schematic the unused LM358 is "tied off" using several resistors.

I looked into this and became convinced that you can tie off the op amp without needing resistors. See photos below for comparison.

However, I'm interested if others have opinion on this. It seems useful to simplify our PCBs if we can get rid of any unnecessary parts.

-SB

Sorry about that.. I wasn't focused on that part of the circuit at all so didn't even look at it!

Thanks for picking up where I left off and completing the schematic. I left the component IDs blank on purpose hoping that someone could make a suggestion.

Hopefully, Andy can make use of the documentation and provide it along with his TGSL kits at his online store.

Don

[Qiaozhi]

I don't know -- I thought you or someone had made a PDF file of the schematic that Don got a hold of -- maybe I'm off in left field...

-SB

The easiest way of turning an image file into a PDF is to paste it into an OpenOffice (or LibreOffice) document, and then export it.

[simonbaker]

Which PDF file are you talking about?

I don't know -- I thought you or someone had made a PDF file of the schematic that Don got a hold of -- maybe I'm off in left field...

-SB

[Qiaozhi]

Or maybe someone else did it like Qiaozhi.

Which PDF file are you talking about?

[simonbaker]

Simon,

BTW.. How did you export to a .pdf?

Don

I can't remember now -- I see my Photoshop has an export to PDF option so I may have converted from bitmap that way. I also have a "PDF" printer driver, could have been that, or even NitroPDF which I have.

Or maybe someone else did it like Qiaozhi.

-SB

[simonbaker]

LM358 tie off

Side note:

I notice on eduardo's schematic the unused LM358 is "tied off" using several resistors.

I looked into this and became convinced that you can tie off the op amp without needing resistors. See photos below for comparison.

However, I'm interested if others have opinion on this. It seems useful to simplify our PCBs if we can get rid of any unnecessary parts.

-SB

[simonbaker]

I checked with Eduardo.. Deleted R37 and added one label on bypass cap.
Don

This is great, thanks!

I added your change history to the schematic notes and renamed it as Rev E.4, put credit to you for changes.

I noticed some new parts do not have an "Id". An "Id" is placed by right-clicking on the component and typing in the name that Eduardo gave the part, such as "R27" or "C54", etc.

I don't know if all the other part Ids still correspond to the names eduardo used on his PCB.

It is really useful to get the Ids correct, because this ".sch" file can be linked to an ExpressPCB layout file for anyone who wants to make an eduardo style layout with that program (cheapo self-flagellators like myself).

I wish I had made a version with Ivconic's bypass caps too. Not too late I suppose.

Regards,

-SB

[dfbowers]

I checked with Eduardo.. Deleted R37 and added one label on bypass cap.
Don

[dfbowers]

Here is the bitmap file as well.

[dfbowers]

Simon,

Here U go.. I changed what I could find. I will PM Eduardo to see if he can double check me before sending the final to Andy (Silverdog).

Most notable, the 100nF bypass caps have been deleted and replaced with a single 100uF cap. I don't really like that idea but does not seem to cause any problems. The 100nF caps don't show on the original schematic anyway. They only show on the parts placement.

C14 and C17 have been replaced with 22uF caps
R29 and R31 have been replaced with 1m resistors
TR9 deleted
R55 and R52 changed to 100 ohms
C27 changed to 220uF
Added 5k6 resistor between base and emitter of TR3
100 ohm resistor added between TR2 emitter and speaker

BTW.. How did you export to a .pdf?

Don

[simonbaker]

I used the onboard pot. The problem is that in the AM mode there is a "range" where ferrite is rejected. It will be accepted on either side of that, and it must be set up on the correct "edge" of the null range, so you have to know what side you are on. When switching to the disc mode, quarters will be rejected on one side (CCW) and accepted on the other (CW) of the GB pot. The only other clue is that you will get a double or single beep with ferrite depending.. in the AM mode. If you GB in the DISC mode you will not notice this "feature"

With Ivconics version, the surface mount pot that I used tunes opposite.

Resistors mount fine. You must make sharp bends to fit in the holes, but no problems at all. The lead spacing for the polarized caps is a little wide but I can still fit them ok. They COULD be about 1mm further apart or use caps with narrower lead spacing. I can measure them and post. Again, not a problem.

Some of the holes have been enlarged as well so all external wires of about 20 gauge fit great now as well as the holes for the 7808.

I will post a revised schematic in the next few days and send a copy to Andy as well.

BTW. do you have an original schematic that I can modify or is the PDF locked? I have been doing screen captures in the past but resolution suffers a little that way.

Don

Hi Don:

Attached is an ExpressSCH schematic, the one I drew for Qiaozhi's sticky "TGSL Complete Details" thread (http://www.geotech1.com/forums/showthread.php?t=15710).

You can modify it with the free ExpressSCH program which you can get here:
http://www.expresspcb.com/ExpressPCBHtm/Download.htm .

It's a pretty easy program to learn, basically just drag and drop, connect lines.

I have modded this schematic many times to create other versions. The mods I have made in other versions include:

1. dfbowers mod on the sensitivity control.
2. voltage divider to reduce ringing in the LF353 DISC driver. (unconventional)
3. simpler way to "tie off" the unused LM358 without extra resistors.

I'm not sure which schematic is closest to the silverdog/eduardo, but the mods were not major. I can send others if needed.

-SB