Let's take a look at a few interesting "polygraph" small circuits, their principle is to detect the skin resistance between fingers. Polygraph circuit 1 This circuit detects the resistance between your fingers to produce oscillation. A dry finger will detect a resistance of up to 100,000 ohms, which will cause the circuit to oscillate at a low frequency. If the subject feels nervous, he will sweat, which will lower the resistance of the skin and make the circuit oscillating frequency higher. The circuit shown in the photo is built into the PC board with a separate touch pad. Polygraph circuit 2 This circuit detects the resistance between your fingers and will cause the FALSE LED to light if the skin resistance drops. 47K adjustable resistor can adjust the sensitivity of the probe when it touches the finger. Polygraph circuit 3 This circuit detects the resistance between your fingers and uses 4 LEDs to show the change in resistance. When you press the detection electrode hard, it will make more and more LED indicator lights. Polygraph circuit 4 This circuit detects the resistance between your fingers. When you press the detection electrode hard, more and more LED indicators light up. This circuit is simpler than the polygraph 3 circuit.
2 Din Android MP5 player with 7/9/10 inch screen options with DPS,ID3 ,Bluetooth ,GPS Nevigation ,Support Mirror Link and rear camera.
ISO socket and special car connector for choosing.
7.0 inch TFT digital touch screen
FM electronic tuning radio, electronic volume control audio / video output
With USB mobile hard disk socket, SD card socket, super compatible format: RM / RMVB FAT16 AND FAT32FILESYSTEMS, WMA / MP3 / MPEG1/MPEG2 / MPEG3 / MPEG4 / DIVX / AVI / MP4 / H263 / H264 / ASF, VOB, DAT, MOV, MKV, FLV, AVI, M4V, PMP, TP, TS, 3GP
Power: 12V, 18 stations can be pre-stored, built-in electronic clock, support pause/repeat/random playback, automatic search for storage stations, support for loudness enhancement mute function
7/9/10 inch 160 million color HD display, support high definition movie format resolution 1280X720DPI
Sound adjustment: bass / treble / balance, audio playback: pop - rock - classic - jazz
Support USB mobile phone charging, with folder function, memory playback function
Optional features: AM electronic tuning radio, RDS wireless remote control, with blue mobile phone mutual screen, rear view camera
Mp5 Car Stereo,Car Mp5 Player,Car Radio Player,Car Stereo Cd Player Jiangmen soundrace electronics and technology co.,ltd. , https://www.soundracegroup.com
With USB/SD/MMC
Compatible with MP4/DIVX/MP5/MP3
18 FM Radio Stations
7388IC,4X45W
Video and audio output,rear monitor video
Built-in Bluetooth
RDS System(optional)
GPS function(optional)