70kHZ transmitter

[goldfinder]

Originally Posted by Mike(Mont)

Just a quick note. Those frequency generators are rejects. They did not pass the quality standards. You pays your money and you takes your chances.

Mike - you must be selling signal generators and don't want any competition. Those so called "fakes" as you have labeled them are state of the art. Better than any I have seen for 100s more. Very reliable, accurate, nice display - can't beat them for the money. They just don't come in a nice case but are a bare bones circuit board with and well done electronics and computerized controls.
Goldfinder.

[Geo]

Originally Posted by epitopios

Dear Geo
Have a look for 2 Schematics ( I have made them) they work just fine separately !!
I didnt try them to to cooperate together
maybe they will help you !!
VLF Transmitter : http://postimg.org/image/58d44lkpv/
Tracer Receiver : http://postimg.org/image/t23g3xo8n/
and pay attention what WM6 said : If you need deep soil penetration then use frequency of about 2kHz, but you will lose sensitivity to small things like tiny gold nuggets.
( if you use a crystal about 10 Mhz at Q12 :4096 for 4060 it will gives you a Frequency about 2Khz !!!
Regards epitopios and .... 73s

Hi Panos.
2Khz is not good frequency for my project because i need very long antenna.
The schema of receiver that you attached is good but not for 100Khz. It need more stages so to keep the same gain (100 for every op.amp).
Regards

[liubing]

GEO Hello, you're doing LRL do?

[mustefa ubram]

Originally Posted by Geo

2Khz is not good frequency for my project because i need very long antenna.
Regards

hi geo.
You can use the electromagnetic antenna in outpou amp or use loop antenna.It does not take a very long antenna.It is suitable for the detection of frq 50 hz to 500kh .
50hz for very deep and big goals and 500kh for normal deep and big or small goals.I built a transmitter and receiver, and it works well.I used the antenna coil. I receive signals from a distance of 50 meters.I have not yet tested for metals., But I believe that this method is effective.my transmitter working in 4.5kh
G.L

[mohandes]

Originally Posted by WM6

If one need a 70kHz transmitter with exact frequency, I suggest this solution:

1.
Use this module from eBay ($38 + free shipping):

0.01- 5MHz DDS Function Signal Generator Module




http://www.ebay.com/itm/0-01-5MHz-DD...-/270864768941


2.

Signal generator has enough amplitude to act as transmitter you need, but if you insist that you need more power, then connect signal generator to this module from eBay:

Mono 25W Audio Amplifier Module Board, Based on LM1875



http://www.ebay.com/itm/Mono-25W-Aud...item5d30720799

Do not drive it with full power - 1/10 of max power, no more.

Inductance of antenna (ferrite core or air core - the last one is better) have to be about 50mH. Exact value depend of antenna windings stray capacitance. You need to connect antenna instead of loudspeaker.

Of course this transmitter can generate any other arbitrary frequency too (for some very different antenna inductance need to be recalculated).

Use sine wave.

thanks
i just need for Amplifier circuit to add signal generator.
if you have Golden king circuit please send here
regards

[Mike(Mont)]

That amp uses AC power. Don't get electrocuted.

[sinclairuser]

Originally Posted by goldfinder

Mike - you must be selling signal generators and don't want any competition. Those so called "fakes" as you have labeled them are state of the art. Better than any I have seen for 100s more. Very reliable, accurate, nice display - can't beat them for the money. They just don't come in a nice case but are a bare bones circuit board with and well done electronics and computerized controls.
Goldfinder.

its not the kits thats a ripoff, its the postage, ebayuk has some like these excellent barebones kits from arizona only 6 quid, but the postage to the uk 39 quid, kits like this cost 42 pounds from maplin over the counter.
some excellent quality kits are available from the states, but if you are outside the states be carefull of the postage costs, dont get stung.

[reza vir]

By the generators and frequency meters Here, the detector can be a good outlet

[WM6]

Originally Posted by reza vir

By the generators and frequency meters Here, the detector can be a good outlet

OK, but how you know which frequency is set? You need here additional frequency counter.

[reza vir]

Originally Posted by WM6

OK, but how you know which frequency is set? You need here additional frequency counter.

Yes, a good result was an accurate frequency meter

[mohandes]

Originally Posted by reza vir

Yes, a good result was an accurate frequency meter

hi
my friend i need golden king or spoofer LRL meter.do you have correct schematic?

and can i use 1MH oscillator for LRL meter ?
regards

[reza vir]

Here I explained to my friend

http://www.longrangelocators.com/for...ad.php?t=19015

yes you can usegolden king is vlf reang