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Hello!
As you've seen in my earlier posts I'm a beginner in building detectors.
I want to built a vlf-detector for very small celtic silver and gold coins.
I have much experience in electronics.
I want to choose a very high frequency because celtic coins are very small (the smallest gold coins are about 4 mm).
Is 32 kHz to high?
My second question:
I want to build a very small concentric coil with outer diameter of 14 cm. Which diameter should the inner coil has? Now, I have 7 cm. Is this okay?
Is it okay if the inner and outer Rx-coils have the same number of windings? Of course, the Rx coil needs much more windings.
The Transmit-frequency is controlled by a quartz.
For the Tx-coil I will use a H-bridge (full-bridge). So I have more power with the same battery voltage.
As I've seen from Fisher CZ-5 they use a half-bridge.
Is it good to increase the transmit power. Or are there any simple limitations?
This little piece of wire to null the coil, is it the end of the Rx or Tx coil?
As you've seen in my earlier posts I'm a beginner in building detectors.
I want to built a vlf-detector for very small celtic silver and gold coins.
I have much experience in electronics.
I want to choose a very high frequency because celtic coins are very small (the smallest gold coins are about 4 mm).
Is 32 kHz to high?
My second question:
I want to build a very small concentric coil with outer diameter of 14 cm. Which diameter should the inner coil has? Now, I have 7 cm. Is this okay?
Is it okay if the inner and outer Rx-coils have the same number of windings? Of course, the Rx coil needs much more windings.
The Transmit-frequency is controlled by a quartz.
For the Tx-coil I will use a H-bridge (full-bridge). So I have more power with the same battery voltage.
As I've seen from Fisher CZ-5 they use a half-bridge.
Is it good to increase the transmit power. Or are there any simple limitations?
This little piece of wire to null the coil, is it the end of the Rx or Tx coil?