- on Microcontrollers
- Published in issue 5/2002 on page 0
Mobile Phone Sniffer
track down mobile phones using this handy directional finder
CAM/CAD data for the PCB referred to in this article is available as a Gerber file. Elektor GREEN and GOLD members can exclusively download these files for free as part of their membership. Gerber files allow a PCB to be produced on an appropriate device available locally, or through an online PCB manufacturing service.
Elektor recommends its business partner Eurocircuits as the company of choice for its own prototypes and volume production in selected cases.
R1,R5 = 100kOhm
R2,R6 = 1kOhm
R3,R7 = 820kOhm
R4,R8 = 220Ohm
R9 = 2kOhm 2
C1,C2,C3 = 100nF
C4 = 100µ F 16V radial
L1,L2 = 10 turns of 0.3-0.5mm diameter (30-24 SWG) enamelled copper wire, internal diameter 5mm (see text)
D1,D2 = BAT43, BAT45, AA112, AA116, AA119
D3 = LED, low-current
IC1 = LM358 P
K1 = STEREO socket for 3.5mm jack plug, PCB mount (e.g. Conrad Electronics #732893)
S1 = on/off switch or pushbutton, 1 make contact
9-V battery (PP3) with clip-on leads
8-way IC socket
Case with battery compartment, e.g., Pactec type K-RC-24-9VB-BC (Conrad Electronics #522864)
Antennae: 2 wire pieces, length 3 to 7.5cm each (see text).