GPX auto tune

[Digginholes]

Hey fellas just wondering what your thoughts are on auto tune and manually tuning the gpx, I see a few times while playing around with the 4500 auto tune is in the high numbers.
What type of effects does the tune have on sensitivity eg: higher Chanel freq less sens or depth on size ?
Or is it simply the channel with least emi?
Cheers

 

[GypsyGoldAu]

The "channel" (ie; 1-255 on a GPX 4K) is a "tuned" wavelength within a band of frequencies. The higher the number (if we're talking about 11" or less coil size), the "finer" it is tuned to "smaller deeper" targets with "some" improvement also at hearing larger/deeper ones, though not by the same %. It is also in finding the "quietest" channel against EMI for the size of your coil in use (think...radio receiver or Rx).

I have found your situation above myself, and also find that this will change the larger coil i use, so it's like an auto adjuster for the gold your looking for & the "most suitable" coil for that gold. The larger the coil i use, the lower the detector "tunes" to a lower number.

Manual will still work when set "low" (55-125 for eg on "small" coils as there are usually various directions to avoid EMI when tuning for that "effect"....lowering the "tune" will also have your coil more "receptive" to the larger/deeper bits of gold at the limit of the coils transmission depth.

Manual or auto....like any other adjustments you make in the field dependent on the ground your on, use what works to give you the best advantage of running your detector to the best of it's capabilities.

Never a set way of doing things.....just what works for YOU at that time, at that day, at that location, in THAT weather....oh, and YOUR ears lol.

Gypsy

 

[Digginholes]

Thanks gypsy

 

[Narrawa]

If you believe that manipulating the tune frequency will give you an edge, think about this.......your threshold plays a much bigger part. Your altering the tune freq because someone says you'll find gold due to that frequency giving you better sensitivity, could come at the cost of losing that gold due to EMI being more round that set of numbers.

Rob Peter to pay Paul......if it gives better sensitivity, it gives better sensitivity all round...EMI....ground noise ect ect. You cant highlight one without highlighting the other.

The R&D that went into the auto tune feature, went into it for a reason. Show me a man that can better pick a quieter frequency in less than a minute using the manual tune feature..... and i'll show you a flying pig.

Coil sizing....
Bigger antenna....up the size of the antenna, and you would expect the tune frequency to account for a stronger frequency if it falls within the EMI level thats being looked at by the auto tune function. The settled frequency/number it rests on, is of a group that was found by the electronics to be the lowest of that set. If you now change directions with your coil, your dilemma can go either way...towards the offending signal, or away from it. Meaning, if there was an advantage occurring from the selected freq, its now compromised by either being slightly less sensitive, or over sensitive for the ground conditions....and level of EMI now present.?

One of the best ways to test the functionality of the auto tune feature, is to place a working PI detector far enough away so thats its being picked up by the one your holding. (very common example when working close by friends )Now adjust your freq manually and see if the old wives tale rings true about sensitivity vs depth.? Effectively, all you'll be doing with the manual tune is.....getting rid of the annoyance caused by working in the same vicinity as another.

Iv been playing with this myth for a very long time, and no one has ever been able to put worth to its validity. And the reason for this is....the amount of variables. Your better off putting the time in prospecting/detecting rather than find any edge from this exercise in my opinion.