Rating the projects

[golfnut]

I hadnt considered both tones together !

I thought one or the other.


I see

Steve

[6666]

The idea of the IGSL was to give the two tones at the same time to tell you that the target it is in fact iron

So is it the same principle being used in the gold scan 4 ?

[Bigjohn]

Surf 1.2 set and pcb

Hi,

I am new to MD and this forum so please go carefully with me.

As I have only just bought the kit I am sure the screen printing for R18 and R22 are correct.

I bought (may 2012) the surf 1.2 kit from Silverdog and I have built it. I made a coil and every thing seems to work but this was from trial and error just twidling the knobs untill I got some noise from it which seemed to correspond with a metal object being waved over the coil.

Is there a correct way of adjusting the "offset" and "delay" with the P2 "tune" pot?

I have a 'scope if this would help.

Just need a little guidence in the right direction. Thank you.

[silverdog]

some good scope pictures for adjusting the surf in this thread
http://www.geotech1.com/forums/showt...t=17240&page=2

adjust offset to give 0v on TP2

[golfnut]

IDX_Pro
Ease of build -
Initial setting up -
Sensitivity 9" mono -
Cost/availability/part sourcing -

Some poeple said they wnated more depth from this kit - I did too. I made the Rx 75% of the Tx Freq and boosted the Tx - not bad now - still not as good as Garrett Pro may mate uses. I get about 1/3rd of what he gets on the day.

I did mine at 11kHz, to get small silver items in UK.
I found the circuitry tolerant to alterations i.e. I run the Tx from the battery direct at 12v with no fires or problems in use. Plus higher freq - I added a fixed resistor in series with th GEB pot to crank it to mid pot.


I can detect a standard brass Yale door key at 9" in mineralised soil - with coil 1.5 inches above the ground for the swipe.
I have found a hammered silver weighing about a 0.5gram 11mm dia with this - at about 3 inches.

My coils were not wrapped in anything.
I attached 4 fine wires to the graphited shell - adhered them using silver loaded paint for heated window repair.. star pointed to the cable shield wire.

I then painted the shell in graphite loaded matt grey pimer for plastic bumpers. ~5k per square.

20T 0.3mm 440nH/470nF cap in head
200T 0.2mm 24mH/22nF cap in box

Box remote on hip clip - - - -1.6M cable to head.

65gram golf shaft for stick + bits of crutch welded up. No good for bashing thru stubble but great for flat soil lawn height grass.

This unit would be better with a full wave demod - as all radios would.

S

S

[satdaveuk]

Was so pleased with the TGSL that I built 2 of them, if built to a good spec you get 6/7" on a pre 1937 silver sixpence in typical UK field using a 8" factory coil, the stem lwr plastic, middle using crutch,upper aerial pole, arm cup varnished cable drum inner suport, housing styreen bits glued together, as you can see its been hammered,goes in the van most days, made some nice finds with it.
Very much a turn on and go machine.
Everythings a 4 for this one , If its discrimination your after they dont come any better.
Second build was housed in a hard drive case, looks really nice and works well, which is just as well because everything is cramned in such a small place incl the 8 rechargable cells.

[Buckrogers]

Looks like the newer Silverdog Surf Pi kits have fixed the PCB labelling between R18 and R22. The kit I have shows R22 now where R18 was originally and so on.

Useful to read the whole thread above to find this out however as I would have gone and switched them if it wasn't for the PCB jpg's above.