Metal Detecting Forums

Metal Detecting => Technical Information => Topic started by: Barney on December 13, 2014, 10:06 PM

Title: Feedback on the Surf Pi modifications
Post by: Barney on December 13, 2014, 10:06 PM
I would just like to share my short experience on the Surf Pi.  I have built the kit supplied by Silverdog.  Luuk have built the correct coil for me and he is the person to contact on technical aspects of the Pi.  What I have added to the standard operating interfaces of the kit is a headphone socket and a signal strength/battery level indicator.  Both these additions proved very useful on my holiday trip to the south coast.  Firstly, operating with no headphones on the beach can prove to be a difficult hunt as the little Piezzo speaker is not loud enough so the signal strength meter giving a visual clue worked nicely.  The battery level tester incorporated is also handy as with the standard kit there is no other way to check battery levels while hunting.  Normally you would use a multimeter and open up the case before every hunt to check battery levels.  I found that with the 8 x 1.5V AA batteries you can comfortably go down to 8V without losing performance.  The best addition was the headphone socket.  It enabled me to set the threshold accurately (also using the signal strength meter in conjunction).  With the head phones the wave noise is subdued and I was able to pick up faint signals enabling me to dig deep - coins up to 30cm and bottle tops up to 40cm.   

I enjoyed using a detector that I have built and it performed really well!  8)
Title: Re: Feedback on the Surf Pi modifications
Post by: Paul van Heerden on December 13, 2014, 11:29 PM
Thanks barney
Title: Re: Feedback on the Surf Pi modifications
Post by: Dennis on January 15, 2015, 01:15 PM
Hi
Barney have you not thought of using two 6 volt gel cells, use the 2 a/Hr size in a water proof housing in your carry bag with a power cable sealed of to the water, one has 24 hours of detecting with out charging.
Title: Re: Feedback on the Surf Pi modifications
Post by: Tony Curnick on January 15, 2015, 07:17 PM
30 cm is impressive Barney....and yip, Luuk is the go to man for help!!....
Title: Re: Feedback on the Surf Pi modifications
Post by: Louis Kriedemann on January 15, 2015, 07:35 PM
the performance from your surf pi is pretty damn good.
30cm on a coin is more than some commercial detectors can give you 8)
Title: Re: Feedback on the Surf Pi modifications
Post by: Barney on January 17, 2015, 09:45 PM
Somewhere I have read that the wet beach sand enhances the performance of a Pi detector. ..... Maybe it is a myth  :D
Title: Re: Feedback on the Surf Pi modifications
Post by: Barney on February 03, 2015, 02:22 PM
I have completed the delay modification on my SurfPi.  The delay setting is normally done on the circuit board but I have replaced the preset trim pot with a potentiometer that is now mounted next to the threshold control on the housing.  With this modification I am now able to tweak the performance wrt sensitivity and I am able to reduce "falsing" on normal soil, ie I can use the Pi on most types of soil without picking up false signals. Changing the delay could also give some crude form of discrimination. However, detection depth might be sacrificed with some settings.  8)
Title: Re: Feedback on the Surf Pi modifications
Post by: Paul van Heerden on February 03, 2015, 02:36 PM
I have completed the delay modification on my SurfPi.  The delay setting is normally done on the circuit board but I have replaced the preset trim pot with a potentiometer that is now mounted next to the threshold control on the housing.  With this modification I am now able to tweak the performance wrt sensitivity and I am able to reduce "falsing" on normal soil, ie I can use the Pi on most types of soil without picking up false signals. Changing the delay could also give some crude form of discrimination. However, detection depth might be sacrificed with some settings.  8)

Well done Barney. You seem to be quite knowkedgeable with electronics
Title: Re: Feedback on the Surf Pi modifications
Post by: Barney on February 03, 2015, 06:54 PM
Well done Barney. You seem to be quite knowkedgeable with electronics

Just enough to help myself with basic stuff Paul  ;).