serial or parallel rezonance in VLF search heads?

[rumensat]

friends let discuss serial or parallel rezonance is beter to use in VLF search heads?
i make several types and thing that serial rezonance give more power but it is terible in heavy soils.
serial rezonance take twice power (serial 300ma, against parallel- 150ma)

[Seeker]

friends let discuss serial or parallel rezonance is beter to use in VLF search heads?
i make several types and thing that serial rezonance give more power but it is terible in heavy soils.
serial rezonance take twice power (serial 300ma, against parallel- 150ma)

Hi , I think parallel rezonance is good for TX coil, but serial for RX coil.You can't increase output power in TX due mechanical soliditi of coils. If you
strike coils in ground or in some obstacle, they will tremble and you will receive false signal. When you use serial for RX , the input impedance is low and you can avoid many of interferences.

[rumensat]

i have not seen such schematic - with serial Rx, may be have to try?

[Seeker]

i have not seen such schematic - with serial Rx, may be have to try?

Hi ,look at the schematic of "Magnum". The input of RX is emitter of transistor,the capacitor connected to base and with RXcoil make serial rezonance.

[Geo]

Resistance adaptation

It is subject of adaptation of resistances. The serial resonance has low resistance and suits more in the transport of power (from the transmitter to the coil). The parallel resonance has high resistance and it is usually used in rungs of entry where the tendencies and the currents of entry are low (Rx).

[Seeker]

It is subject of adaptation of resistances. The serial resonance has low resistance and suits more in the transport of power (from the transmitter to the coil). The parallel resonance has high resistance and it is usually used in rungs of entry where the tendencies and the currents of entry are low (Rx).

Hi Geo,
In fact impedance is determinative in choice of serial or parallel coil, not resistance. For RX parallel circuit is suitable for high impedance ( gate of MOS transistor) , serial for low impedance ( to emitter of bipolar,base is to ground ), no matter how big is signal as power.

[Geo]

Hi Geo,
In fact impedance is determinative in choice of serial or parallel coil, not resistance. For RX parallel circuit is suitable for high impedance ( gate of MOS transistor) , serial for low impedance ( to emitter of bipolar,base is to ground ), no matter how big is signal as power.

Hi. We say the same things with other words. High power at low voltage means low synthetic resistance (Z) R=P/I^2 . High tenses with high current means high power (P=U*I). I agree that impedance is the exactly term.

[rumensat]

the matter of fact is that nobody make serial attack in tx coil. (big producers).
that is only russian idea and every day i see that is not right way.
pushing the power of Tx going only to big reflect from soil and beep on every stone and moist soil. rezult is mass diging and find nothing, only in see sand rezults are good.