In this article we show another 16 kits that are ideal for beginners
Voice-activated melody light
A fun little kit where the LEDs flash based on music/sounds. Cost about $1.60
Doorbell DIY Kit
Only $0.59 for a 555 timer based doorbell kit. It needs 4 to 7v. The speaker is rated at 8 Ohm 0.25W so it has a reasonable volume for the job in hand.
Multi-channel Waveform Generator kit
This NE555 multi-channel waveform generator can produce square wave, sawtooth wave, triangular wave and a sine wave. You use a jumper to select a waveform output, the circuit is simple, easy to operate. This kit costs about $2.25
3D Christmas Tree LED DIY
A little bit of fun for only $2.20, not much to the kit basically a christmas tree shaped PCB with LEDs. A fun, seasonal kit that the kids would love – could be an ideal introduction to electronics
Electronic Windmill Training Kit
The circuit is based on another STC microcontroller, the microcontroller controls the LEDs, so as to achieve the effect of a windmill rotation, you can change the speed of the windmill flashing through the button. Its fairly basic but fun and comes in at $2.40
LM358 LED Breathing Light Kit
This uses another very popular integrated circuit, this time its the LM358. Tis does require 11 to 13V.
Mobile Phone Signal Flash Light DIY Kit
Phone call lights kit can be used to sense the GSM signal display, sensing distance up to 1 m, it is a very interesting DIY kit.The main circuit is amplified antenna sensor signal circuit and circuit. Sensing signal through the antenna 3 to S8050 transistor amplifier to drive the LED, so that light up. When no signal is detected, no calls or no GSM phones, LED circuit is not only detects the signal to light up LED. Under $1 for this kit.
TDA2030A Electronic Audio Power Amplifier kit
TDA2030A is another audio amplifier, this one can supply 18w and the kit only costs $0.60. The specs are interesting.
Output Power: Maximum 18W
Supply Voltage: DC 9V-24V(recommended DC 12V, this voltage to the heat sink requirements are very low; Maximum supply of this board is actually up to 40V, but you need to change the board’s own electrolytic capacitor C1, the capacitor voltage value is higher than supply voltage can be use. )
Static Current: about 25mA (disconnect to tone, connect to 8Ω speaker, 12V power supply. )
Speaker Impendance: 4Ω-8Ω
Total harmonic distortion: THD 0.08%（Po=0.1 to 14W，RL=4Ω）
DIY heart kit
$2 for a LED heart kit which you can get in 4 different LED colors
DAC Waveform Generator kit
This needs + and – 15v to power the DAC0832
DIY Kit Metal Detector Kit
A very simple metal detector kit
LM3915 Audio Level DIY Kit
LM3915 audio level indicator kit which requires 9V-12V. The kit comes in $1.15
LM317+LM337 Dual Power Adjustable Kit
An improved PSU kit which has a positive and negative voltage regulator
Input voltage: AC 5V- double dual AC 20V (only dual AC input)
Output DC: 1.3-25 V
Current: 1 A
Surge mode: linear buck regulator, the output voltage of the AC voltage is rectified and filtered after minus 3V.
After such input dual 12V, the regulator rectifier filter voltage is above 12 * 1.414 = 16.968V, the output voltage can 16.968-3V = 13.968V
LED dice kit
A very simple dice based kit based around the popular 555 and 4017 integrated circuit combination
LM1875T 30W amplifier DIY kit
An even more powerful amplifier kit, this one uses an LM1875T 30W amplifier
Output power: typical 20W (Max. 30W)
The speaker impedance: 4 Ω – 8 Ω
Total harmonic distortion: < 0.04%
Signal to noise ratio: 105dB
Frequency response: 14hz-100khz (maximum range calculated by RC high-low power circuit: 3.29 hz-482.29 kHz)
Power supply voltage: recommended ±25V (highest voltage shall not exceed ±30V, full bridge rectification of 18V is 25V)
Electronic Red Blue Double Color Flashing Kit
This kit has a NE555 and CD4017,the blue LED and red LED flashed alternately according to the pulse. The multivibrator composed of NE555 will have a certain frequency of oscillation signal send to CD4017 decimal counter/pulse distributor,in order to count. When the 1,3,5 pulses arrive Q0,Q2,Q4 output high level in turn,blue LED flashes 3 times,Q5,Q7,Q9 output high level in turn.Red LED flashes 3 times,blue LED flashes again when 11,13,15 pulses come,blue and red LED flashes alternately circulatory,so as to like the alarm lamp.Change the RP1 size can change the oscillation period, thus changing the LED shining speed, the whole circuit DC9-12V can be worked.
Red flashing light and blue flashing light form a board separately,connected with the main board through the stamp hole.If you need to install to other place separately or increase the distance,you should cut off through the stamp hole,then connect with the mother board by two wires.Please pay attention to the direction of LED when installing,especially the direction of L11 and L12.The R2 and R3 controls with the brightness of light,you can change it appropriately ,the range is 10-100 ohm.
supply power : 9-12V