Inside the TX-2002 pinpointer

[Qiaozhi]

Backlighting really shows up thin tracks well.

There is no need to backlight the board. As long as you have a clear image of both sides, you can use GIMP to flip the rear view, place it on a second layer, and allow it to show through by changing the opacity of the top layer.

What is the largest file size JPG image I can attach here ?

png, tif and jpg have a size limit of 1MB.

[mr.sneezy]

Bare board images.

Here are three sets of images. The first pair is done as you wanted (outdoors under open sky), the second pair is under studio lighting (controlled lighting with minimal glare) and the last pair is back lit. Use whichever your suits you.

I think that now covers the four steps below the project needs from me.

"1. board with components pics in hi resolution at sunny day at open air.
2. desoldered board. pics in hi resolution, of both sides, at sunny day.
3. full part list. every components must be measured individually, not via color code only looking.
4. all transistors must be researched by haracteriograph, or tested on matter they are PNP or NPN structure of."

Let me know if not, as I'll put the board back together otherwise.
I'm very curious to see the schematic and see what the heck is supposed to be going on...

Cheers,
Martin

PS. The tracks from D9 back to itself via pin1 of both IC's are interesting
(unless I'm wrong).

[mr.sneezy]

Oh yes, I nearly forgot. I took additional populated board shots in case the ones I posted on day one were not good enough. Plus there is a shot of my last testing ferrite coil winding (that worked best).

Martin

[mr.sneezy]

you can use GIMP to flip the rear view, place it on a second layer, and allow it to show through by changing the opacity of the top layer.

Can you post up a saved GIMP image of this technique when you do it, be nice to see what a pro can do with GIMP.
Martin

[greylourie]

Is there a Gimp for Windows ?

[greylourie]

Is there a Gimp for Windows ?

For anyone interested, here is the link for Windows versions http://www.gimp.org/downloads/

[kt315]

thank lots Martin for your home work. as I promised, you can get all archive of this forum on DVD for free. give me your snail mail address (in PM) and I will send you the disc.

[walkman]

kt315, I want free DVD. I send to PM

[walkman]

Wow, impressive given the short amount of time. Yes, you have some missing tracks, but tomorrow (late) you will have HiRes images of the top and bottom faces of the bare board.

I have a plan to use a light table to backlight the bare board as well as do a regular image of each side. Backlighting really shows up thin tracks well.

Please see the final draft of the Parts List, as there are a few corrections in it now, plus 'as measured' values as all parts were removed tonight.

Looks at first glance that the 4011 is partly being used as an inverting buffer....

Martin

PS. What is the largest file size JPG image I can attach here ?

Thanks for answers. mr. sneezy. But, some knowledge of the components and coil Could you give value?

[sinclairuser]

thanks and nice job mate, i know someone who has one of these, i'm trying to borrow it, i cant promise to "field strip" it as you have done.
but i replaced the led for him and i'm almost sure that his board is fully populated, so photos of that board and coil measurements may help a little.
if a board has missing components its always nice to know what they do.

[Qiaozhi]

Can you post up a saved GIMP image of this technique when you do it, be nice to see what a pro can do with GIMP.
Martin

OK - here it is.

[mr.sneezy]

OK - here it is.

Very nice work, that make following the tracks very easy.
We have a long holiday weekend coming here so I won't be putting the unit back together till after that. I'm packing my main detector and hoping to do some beach hunting.

[mr.sneezy]

thanks and nice job mate, i know someone who has one of these, i'm trying to borrow it, i cant promise to "field strip" it as you have done.
but i replaced the led for him and i'm almost sure that his board is fully populated, so photos of that board and coil measurements may help a little.
if a board has missing components its always nice to know what they do.

I can't see that a strip down would reveal much, but perhaps measuring the coil values might be useful, as well as the parts you think might be popluted on his unit.
Thanks,
Martin
PS. I intend to see if I can melt the glue around the OEM coil in boiling water and see if I can slip it out, but that will be middle of next week.

[mr.sneezy]

Thanks for answers. mr. sneezy. But, some knowledge of the components and coil Could you give value?

Hi Walkman, you can find the final (now correct) parts list with values on post #30, in PDF and XLS file type.
The coil value is in there too in the list.

Be aware that on Qiaozhi's merged picture that the unmarked rectangular component above K1 was fitted with a normal axial resistor (2k4). It might have been for a trim pot originally me thinks.

[kt315]

kt315, I want free DVD. I send to PM

you do not want DVD because DVD you got. you want Inside The Metal Detector scanned, which is copyrighted. ask George and if he will agree to send you
files I will do. if not so that is not.