Pinpointer Velleman k7102
Drilling a hole in the walls with an electrical conductor or buried cable can turn into a real tragedy and serious consequences. If you are digging paths for gas, water or central heating pipes, it is also a big risk. But a very simple metal detector can solve this big problem.
Velleman k7102 It is a very simple and convenient device that allows you to check in advance whether metal objects are present in walls, floors, ceilings and even concrete columns. A simple metal indicator indicates whether you are near metal objects. Coin collectors can use it as a Pinpointer to determine the accuracy of the metal because of its small and portable hand.
- Adjustable metal detecting depth: up to 8 cm
- Battery: 9V battery
- Light indicator
- 12-volt speaker connection
- Small Dimensions of printed plate:
Velleman k7102 schematic diagram
The following figure illustrates the scheme of the device and the principle of its operation
The necessary electronic parts for designing this device are shown in the following picture:
Based on the above diagram, the printed circuit board can be designed as you like and according to the box where you want to embed the device in:
After assembling the device it will look like in the picture which is very simple so that the beginners are able to assemble the device.
Designing of Coils L1 and L2.
The search coil consists of two elementary coils wrapped around a ferrite rod. In order to facilitate winding, it is possible to place a double-sided end strip on the ferrite or fix the beginning of each winding with a normal coil. The direction of both files must be in the same direction. The first coil L1 consists of 120 turns and the L2 coil of 43 turns.
Test and final adjustments
- Connect the a 9V battery to the device
- Go to a place where there is no metal.
- Turn the RV1 handle clockwise to its end.
- Press the push button and hold it down until the end of the adjustments.
- Turn the RV1 counter clockwise until the led turns off.
- All other remaining modifications are now for RV2 only.
- To set the maximum sensitivity: Turn the RV2 until the lamp lights poorly. Then comes the detection of the metal object, the lamp will become more illuminated and this gives an indication of the distance or size of the metal object.The device can be purchased from its original location: