Aka Signum MFT 7272M version 100c User Manual

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Селективный металлодетектор «Сигнум MFT» 7272М. Руководство по эксплуатации.  
 
 
 
This useful component of the vector is the projection of AB to the vertical Y axis. The 
smaller  the  angle  difference  between  the ground  signal vector  and  the  vector  of  the  coin 
the less useful part of the projection of the signal and the less sensitivity. More important is 
the  fact  that  the  angular  difference  becomes even  less with  the  so-called  hot-stone  (see 
fig. 26). 
In  these  cases, even  a  minor incorrect  setting  of the ground  balance  can  lead  to  a 
significant  loss  of sensitivity  to  the  large copper/silver coins or  an  undesirable  (annoying) 
response to hot rocks if the algorithm DHR is not used. 
Note that when setting the ground balance, such  as on loam, the angular  difference 
between  the  signal  and  the  signal  of large  copper/silver  coins  is about 7-8  degrees.  At  the 
same  time,  the  angular  difference  between hot rocks is  only  4-5  degrees  which  leads  to 
difficulties in the identification of such targets. 
In view of the above, it is possible to give some practical recommendations. 
1. As accurately as possible carry out Ground Balance. 
2. In areas with little to no metal trash use the AGT. 
3. In the presence of hot stones, when not using the DHR algorithm, carefully open 
up the  right  border  of  the  sector  discrimination to  minimize  the  risk  of  missing 
these types of coins. 
4. Try to adjust the vector phase of the soil by 2-3 degrees in the counterclockwise 
direction  (specific value selected  experimentally  in Depending  on  the  type  of 
soil). To do this, perform the automatic ground balance procedure. 
 
        Then press the button             to enter into manual ground balance mode 
 
        and adjust the balance value 2-3 times by pressing              and then check the  
 
response  of  the detector when  scanning  area  clean. This  procedure requires  a 
more  careful  scanning  of  the  soil.  In  the  case  of  false  positives  channel 
identification (ST) reduce the angle of the phase by pressing  
 
button              until their disappearance. 
 
When  searching  on  the  wet  grass (dew, rain) there  is  an  increased  risk  of  false 
signals in the ST channel. This effect manifests itself mainly due to the setting of high values 
of  sensitivity in  the  ST channel and to  the  presence  of  a  weak  electric  conductivity  in  the 
dew  and  plant liquids. To  a  large  extent (almost completely),  this  effect can  be eliminated 
by placing the search coil in a protective plastic case (plastic bag, full-time protection, etc.). 
In  the  case  of  searching  in  trashy  areas it is  sufficient  to  reduce  the  sensitivity  of  the ST 
channel. 
 
 
 
 
  
						

							Селективный металлодетектор «Сигнум MFT» 7272М. Руководство по эксплуатации. 
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EXAMPLES OF  SOME  COMMON  TARGET 
VDI’s 
VDI  data  are  for  units  with  a  7  kHz, Normal  mode,  Turbo  and  Economy  off  and  DHR 
off.  
 
Scale Of VDI Items 
From -90 to -86 Hot rocks, improperly configured ground. 
From -86 to -70 small nails and other small iron trash. 
From -70 to- 50 medium wrought nails, small arrowheads. 
From -70 to -35 large  wrought  nails,  medieval  knives,  flat  arrowheads,  horseshoes, 
locks, and other fairly large iron articles. 
From -35 to -10 In  this  sector  there  is  little  iron  accept  those  targets  that  may  be 
“masked” by  iron, small  objectV of  irregular  shape of  the low 
conductivity of  non-ferrouV alloys (bronze crosses, thin  gold 
Verpentine chain). Pay particular attention  to  the arrow and  narrow 
loop-travel times in this sector. 
From -10 to +10 foil, small crosses of bronze, very small lead, fine golT, small .22 shell 
casingV. 
From +10 to +30 Hammered short cross silver cut half (+22)H Roman minim (+14), some small thin hammered silver coins, US 5 cent nickel,50 pence (+24), 20 pence (+28),small lead shot. 
From +30 to +50 Hammered short cross silver penny +47, Celtic gold stator +46-+50, larger lead shot( i.e. musket balls, Minnie balls) also lead seals, Aluminum tabs, larger 14K gold rings. 
From +50 to +70 AE antonianus + 64, US copper penny, US zinc Penny, UK pound coin 
From +70 to +86 Large  copper  coins (cartwheel  penny,  King  George  coppers,  Victorian 
penny,) UK  pound  coin, US  dime,  Quarter,  Half  dollar  and dollars,  as 
well  as  large  Planar  or  spherical  iron  objects  (helmets, ,  plows,  axes, 
etc.)  
From +86 to +90 ground response  from  an  unbalanced  device,  hot  rocks,  as  well  as 
very  large  objects  from  deep  highly  conductive  metal  (e.g. aluminum 
basin,  a  large silver tray).  Hot  Stone signals  differ  in  that they sound 
stretched,  while  the  signal  from  the  metal  target  is  usually 
concentrated in a small point. 
As  we  can  see, even  in  the  good  VDI  sectors  we  have  targets that  are  trash.  That  is, 
there  will  always  be  trash  items  mixed  in  with  the  more  desirable targets with  very  similar 
characteristics. 
Also,  do  not  forget  that  the  purpose  of  VDI  is  only  true  in  the  area  of consistent 
definition of the instrument and in the absence of other metal objects nearby. For example, 
a piece  of  iron  underlying  a  gold  ring  will  cause  the  normal  VDI  of +37 to  now  read 18/22. 
And at the limit of sensitivity in the ground, it may suddenly sound like a deep copper coin 
with VDI +85. This is not unique to your device, but for all other devices of this type. 
 
  
						

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Селективный металлодетектор «Сигнум MFT» 7272М. Руководство по эксплуатации.  
 
 
Thus,  any decision  to  dig  or  not  dig  a  likely  trash  target is  a  compromise  between 
comfort verses the  loss  of  valuable  finds.  And  who  knows, maybe 99  times  you  dig  a  trash 
target but on the 100th time the same VDI rated target will turn out to be a valuable find. 
Attention!  When  using  a search  coil with  a  low  frequency  excitation  current VDI 
readings will have lower values. Conversely, for higher frequency the VDI readings will be 
higher. 
      WARRANTY INFORMATION 
Manufacturer guarantees operational capability of the metal detector provided 
that the consumer follows operation conditions. 
Warranty period 24 months starting from the sale date. Manufacturing defects 
shall be repaired by the Manufacturer during the warranty period free of charge provided 
that there is no damages in electronic module and searchcoil. 
This Operating Manual with the sale date mark should be provided together 
with the device in case of warranty repair. 
Warranty period is calculated from the date of manufacture in case there is no sale 
date mark 
 
.Address for claims: 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
						

							Селективный металлодетектор «Сигнум MFT» 7272М. Руководство по эксплуатации. 
34 ООО «фирма «АКА», +7(495)621-0481, http://aka.2000.ru  [email protected]