LOOKING FOR GOLDSCAN 4 Schematic.

[6666]

Looking at the RS website, they say that a 2N5459 should work in a 12volt circuit ok,
be carefull of the legs.

[Orbit]

2n4393 is tested the original GS 4 works exactly the same as j113 ,I'm that supersedes j113 ,all the best !!!!

[maikl]

I love watching my GS4, that will not stop ringing in the back of my house by the trash,

Hi Jose.
Tell me some information GS4 detection in air, for example coil 30cm, with maximum sensitivity:
- can of Coca Cola 0,33 l ...?
- 1 euro coin ...?
- small earrings ... ?

[Jose]

Maiki, detection in air depends inter alia on the noise picked up by the coil when testing in the house or the workshop, in the countryside away from power lines may increase the distances.
Tests in the air inside the house, "OFF" mode, coil 30 cm, maximum gain, delay set to 13 useg. Approx.
The old coin 100 pesos, more than 35 cm.
25 cent coin, 2.5 cm diameter, bronze or nickel alloy, 35 cm.
10 cents coin bronze, 28 cm.
Gold engagement ring, 34 cm.
Small gold earring, 5 cm.
This photo shows the slope, is best detected with smaller coils.
Coke can of 333 cm3, 70 cm.
José

[maikl]

Thanks for the answer Jose. These are good results. Tests are of course in-house, but switched off the TV and computer...
I forgot to point out that the small "gold" earring, but you understand me.
Best regards.

[Jose]

Maikl, this dual coil, works best for small items like gold earrings. The scope is larger and is more intense signal, the values of the damping resistors are what worked well in my GS4, but may vary depending on the characteristics of the MD used.
Jose

[maikl]

Jose, I've tried various types and forms of coils, I've found that simple things work best. I do not like the way it works "dual coil". I small gold earrings (same as the ones on your photo) better detected with a 30 cm coil, than with the coil of 15 cm (mono coil).

[Jose]

Maikl, according to what you say, is probably my single coil, not perform as expected, (mono coil).
Jose

[maikl]

No you're not the only one ... I see your mono coil is not "fast coil"...
Best regards.

[g.s]

just started to build goldscan iv And I understand that it pcb is identical to the PLEASE SEE IMAGES.has two 555.

[mollax]

one 555 of the sound
one 555 of the power supply

[makedonyalı]

GS IV 1x1 large bobine oM be

[ABDW9]

Hello all, my brothers
Not only left last step I
I can not get this diode


BAT49.pdf
BAT85.pdf
1N914.pdf


Can I use 1n4148 instead of them?

[Davor]

You can replace 1N914 with 1N4148 as they are basically the same thing.
BAT49 and BAT85 are schottky diodes and their barrier voltage is considerably lower than regular silicon diodes. You can't replace them with 1N4148 because their role is to protect JFET gates that also have a somewhat lower barrier voltage than silicon diodes.

[Jose]

Try getting germanium diode, 1N60 I got worked well.
Jose