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Frequency and trash
Posted by: kevinnc
Date: March 23, 2019 11:25PM
I have read many times that higher frequencies are better in iron, but I recently got a Makro Multi Kruzer and it seems to do best in iron and trash in 5khz. It is way harder to run in 19khz because of false signals on iron and high toning small trash. It almost ignores the iron in 5khz. Does anyone else use one and see this?

Re: Frequency and trash
Posted by: Flintstone
Date: March 24, 2019 06:30PM
Hi Kevin, I have a XP, and a place with a lot of trash and iron, I will try the low frequency next time I go there. I was thinking about giving up because of trash and iron. I have pulled two rings and a silver dime out of there. Thanks for the thought. I will let you know how it works.

Re: Frequency and trash
Posted by: kevinnc
Date: March 24, 2019 07:47PM
Cool. Look forward to seeing how it does. My Kruzer nails coins and seems to ignore the small iron and trash.

Re: Frequency and trash
Posted by: chuck, ky
Date: March 25, 2019 04:54PM
Why would you just give up on a spot because of trash instead of just eliminating the trash with discrimination?

Something to consider on frequencies:
Posted by: vlad
Date: March 25, 2019 06:52PM
Frequencies are not equal for many reasons in a variety of factors; I'll touch on one, or two.
Different frequencies often have differening levels of transmit power; at the higher frequencies it is easier to fill the Q of the loop because they contain more energy. A lower frequency
like 5kHz (vs 19kHz) requires more battery battery power to raise the energy level, yet they are often set, milder (to conserve reserve). And even a higher frequency (30kHz for example)
is still very sensitive to iron. (some units have a fixed transmit level, others may be variable--check your user's guide) So a sensitivity number across several frequencies will have varying performance.
And for some reason at some point the sensitivity level will false on rejected targets that at a lower setting you do not hear. On a Teknetics Mk-1 @ 6.592kHz I found that an extremely high sensitivity
setting would cause iron to appear that was completely rejected at normal sensitivity. (also recall that a conductor weakens a detector's field, and iron strengthens it,
so iron depending on alloys, shape (BC's), size/halo can have some odd effects--and the field alone suddenly being stronger might cause a frequency shift which is detected in the transmitter and unbalances
the receiver--causing an audio (and these units are not exactly off resonance discriminators!) :rofl:
Make sure you rebalance the ground when changing frequencies (very important) and experiment with the sensitivity settings. And often rejected targets near a notch edge may come
through at a higher setting)
IF you can vary the transmit setting, a higher setting can often be used to overpower emi, and even allow the sensitivity level set lower if needed--with an increase in depth.) :detecting:

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