question on MHz and kHz (please help)

[Eddie Fl]

I'm a little confused on the whole depth thing of detectors. According to what I'm reading when using a frequency of 1.5 kHz on the Minelab the signal travels to max depth and 100 kHz is more sensitive for close to ground objects. So this is leading me to believe that max depth is found at 1.5 kHz. If this is true how can other detectors come close with low kHz's of only 7.5 or 9.5 etc. or one frequency models at 7.5 9 etc. I'm trying to choose a detector for the specific function of all metal depth searching as I will be searching in almost trash free areas with really no mineralization where I will dig any hits whatsoever. Can anyone help? Thx in advance.

 

[WVAdirtdigger]

Khz=Kilohertz=1000Hertz=1000 cycles per second
Mhz=Megahertz=1,000,000Hertz=1million cycles per second

As far as your problem goes MHz is not applicable. That is where radios like the police, EMS operate.

Audible frequency range is 20Hz - 20Khz. So, basically detectors operate in the audio range of frequencies. Sound travels better in water explaining why we get better depth in wet ground. Yes, you get more depth with 1.5Khz than 100Khz but higher frequencies are more sensitive to gold and small items. There is not a lot of difference between say 1.5Khz and 7.5Khz as far as depth but higher than that, you start to lose depth. Depth is also affected by transmit power and receive sensitivity of the detector. So frequency isn't all that affects depth.

This is my understanding of it. Others can chime in if I screwed up any of it.

Dave

 

[RingProfessional]

n/t

 

[Boony]

Hi Eddie Fl,

If your after a coin and relic detector, you won't go past the Explorer II from Minelab, you only have to look around this forum to see how well they perform, if you decide to go for an Explorer II get a copy of Andy Sabisch's book "Mastering the Minelab Explorer XS & S" it's 99% relevant to the Explorer II and cuts down the learning by heaps.
Look forward to pics of your finds.

All the best......Boony

 

[au4greg]

Depth is Signal to Noise.... More Volume on the Signal relative to metal type and size v ground reactivity.

Explorer's FBS of 28 Frequencies.... 1.5 kHz is your best ground penetrator and ability to deliver the best possible signal on a high conductive copper/silver.

The other frequencies seem adept at helping to cancel out other magnetic interference such as 60 cycle power lines.

A higher frequency detector such as the White's MXT or Tesoro Tejon will see some elusive gold items not seen by the Explorer Silver Magnets as they concentrate their transmit voltage at 14.8 and 17.5 kHz.