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The Pulse Devil Nemesis photos have been released on Prospectinginoz Web site and now here. Also I have included the text of some information from that site on to the controls functions. All updates on the Nemesis or questions can be viewed on Dougs site. When I receive the Nemesis test unit I will post results here and maybe on Dougs site as I may well still be in th field testing and will call Doug or Dave to let them know of the results. I am leaving the photos at the normal resolution so there is no loss as Dave sent them to me so the site may look a little deformed when you view them... Click read more to view the rest of this article...


This is written by Doug and was extracted from a post on ProspectinginOZ:

This is from my hand written notes given to me over the phone by Dave.If there are any errors then they will be corrected by Dave when he is well enough to post a detailed explanation of the Nemesis controls and their functions. Dave I hope I have not stuffed up!

Front panel

Frequency Control

This is adjusted from minimum to maximum to get rid of any EMI noisefrom another nearby Nemesis or ML detectors. It is turned until any EMI noise is either nulled out or minimized.

Gain control

This controls the overall circuit gain on the Nemesis and turns it on off. The off position is fully anti clockwise and when just turned on the the circuit gain will be at the minimum position and fully clockwise at the maximum gain position. This will be adjusted to suit the prevailing ground conditions,or any EMI noise and will be used in conjunction with the RETUNE control.

Threshold Control

This is adjusted until the first stable and audible tone is heard through your speakers or headphones. The fainter the audible threshold the better the sensitivity and depth of the Nemesis. If the gain is changed then the threshold should be readjusted. The push button on the handle will instantly re tune the Nemesis to your preset volume and pitch.

Ground Balance

This is a ten turn pot with the inner range being 1-10 and the outer range being 1-100. The Nemesis is a MANUAL Gb detector. GB is achieved by slowly raising a lowering the coil and listening carefully to the threshold volume change(just like the old VLF detectors). If if decreases as the coil is lowered than the GB must be increased by turning it clockwise and conversely if the threshold volume increase as the coil is lowered then the GB must be decreased by turning anti clockwise. The GB adjustment will be made initially with the coarse control and then fine tuned with the outer control. The GB should be adjusted until there is no audible change in threshold volume when the coil is raised or lowered. I would advise that the re tune speed should not be set to fast when ground balancing as this may make the change in threshold volume harder to hear. As with all detectors optimal

performance with the Nemesis will be obtained with perfect ground balance. It is important to note that the Nemesis does not have an auto ground balance or tracking like the ML. The reason for Dave going this way is that you get maximum sensitivity and depth with a manual GB. In particular deep targets whose signals change slowly tend to be nulled out by auto GB tracking circuits. Again if you make any change in the gain or frequency I suggest you recheck the GB.

In part 2 I will discuss the re tune speed auto and manual modes and the discrimination and blanking controls. The discrimination controls are set up very differently for gold prospecting and coin/relic hunting and for very for high and low trash areas. If set up incorrectly for gold detecting then one can lose nuggets so that it is vital that people understand these controls. It also needs to be understood what the limitations of the discrimination are, as it is NOT perfect and there are rare situations where nuggets may be discriminated out eg a small nugget sitting right beside a large piece of iron trash or a nugget sitting on top of or underneath a large piece of iron trash. I will also discuss the differences in signal responses with the blanking control set to normal and blanking.

DouginOz



















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