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Latest Issues

July 2008

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C I R C U I T L A B

1) Aquarium Probe (New)
2) Bicycle Indicator (New)

Click to view in order of 'highest hits first'

S No.	Circuit Name	Hits
1	Poor Man’s Hearing Aid	685
2	Portable Lamp Flasher	1156
3	Staircase Light With Auto Switch-Off	2963
4	Car Anti-theft Guard	2101
5	USB Power Booster	4444
6	Smart Vibration Sensor	3649
7	Drinking Water alarm	6130
8	GLOW PLuG CONTROLLER	3000
9	Versatile CMOS TTL Logic And Clock Probe	2151
10	Tester For Remote Control	5540
11	Automatic Low-Power Emergency Light	10088
12	Mobile Bug	11298
13	LED Lighting for Christmas	8999
14	Current Sensor	9423
15	Seismic Sensor	8327
16	Dice With 7-Segment Display	6432
17	Motorbike Alarm	10806
18	Laptop Protector	14348
19	Shutter Guard	6547
20	Desktop Power Supply	10439
21	Mobile Shield	15071
22	Infrared Firecracker Igniter	10887
23	Automatic Phase Changer	11605
24	Flying Saucer	14704
25	Anti-Collision Rear Light	12128
26	Light Fence	12681
27	MAT Switch	10615
28	5-Band Graphic Equaliser	10210
29	Clock Timer	17899
30	Fully Automatic Emergency Light	22326
31	IR Music Transmitter and Receiver	26523
32	Electronic Horn	16081
33	Ultrasonic Proximity Detector	19204
34	Secret Bell	22504
35	Variable Power Supply Using a Fixed-Voltage Regulator IC	26511
36	Appliance Timer-Cum-Clap Switch	13169
37	Telephone-Operated Calling System	19159
38	Front Door Guard	20159
39	Bell-Cum Light Controller	13306
40	Friendly Charger for Mobile Phones	22270
41	Hearing Aid	17440
42	Speed Control of DC Motor Using Pulse-Width Modulation	23065
43	Remote-Controlled Fan Regulator	38347
44	Low-Power Voltage Doubler	14614
45	Parrot-Sounding AC Doorbell	14630
46	Multi-Melody Generator With Instrumental Effect	11131
47	School/College Quiz Buzzer	13738
48	Visual AC Mains Voltage Indicator	14149
49	Simple Short-Wave Transmitter	15332
50	Solar Lighting System	39593
51	Infrared Bug	25187
52	Picnic Lamp	20779
53	Versatile Power Supply	22097
54	Ultrasonic Proximity Detector	26964
55	Shadow Alarm	29507
56	IR Burglar Deterrent	31339
57	Versatile Water-Level Controller	26123
58	Automatic-Off Timer For CD Players	18757
59	Heat-Sensitive Switch	20987
60	Sensitive Vibration Detector	20847
61	Digital Dice	22869
62	Remote-Controlled Power-Off Switch	37468
63	Little Door Guard	27184
64	Stress Meter	25386
65	Teleconferencing System	29687
66	Medium-Power FM Transmitter	32817
67	Smart Cellphone Holder	26748
68	Fuel Reserve Indicator For Vehicles	24404
69	Brake Failure Indicator	26628
70	Safety Guard	20372
71	Mains Supply Failure Alarm	21576
72	Remote Control For Home Appliances	61351
73	Micromotor Controller	30448
74	Solar Bug	32384
75	Simple Digital Security System	36620
76	Digital Audio/Video Input Selector	20589
77	Auto Turn-Off Battery Charger	37830
78	Atmel AVR ISP Dongle	27104
79	Audio Amplifier for Personal Stereo	37658
80	Musical Light Chaser	31721
81	Water-Level Controller	53244
82	Hit Switch	33725
83	Fire Alarm Using Thermistor	32455
84	Electronic Watchdog	44494
85	Automatic School Bell	28977
86	Anti-Theft Alarm For Bikes	42263
87	DC Motor Control Using A Single Switch	33741
88	Solidstate Remote Control Switch	31512
89	Flashing-Cum-Running Light	28106
90	Quality FM Transmitter	63280
91	Stabilised Power Supply With Short-Circuit Indication	27941
92	Digital Stop Watch	38518
93	Cell-Phone-Controlled Audio/Video Mute Switch	44407
94	PC-Based DC Motor Speed Controller	48521
95	Child's Lamp	36987
96	Watchman Watcher	32736
97	Highway Alert Signal Lamp	25637
98	Low-Cost Electronic Quiz Table	23614
99	Mobile Cellphone Charger	56981
100	Smart Foot Switch	29339
101	Programmable Timer for Appliances	45659
102	Anti-Bag-Snatching Alarm	25083
103	LED-Based Message Display	67517
104	Multiband CW Transmitter	27733
105	Automatic Night Lamp With Morning Alarm	50918
106	Touch Dimmer	46401
107	Mosfet-Based Preamplifier for FM Radio DXing	32380
108	Non-Contact Power Monitor	24625
109	Remote-Operated Musical Bell	40900
110	Electronic Motor Starter	44118
111	Telephone Receiver	63201
112	Washing Machine Motor Controller	41069
113	Low-Cost Hearing Aid	37666
114	Over-/Under-Voltage Protection of Electrical Appliances	33214
115	Parallel Telephone With Secrecy and Call Prevention	38461
116	Voltage-Based Controller For Switches	22412
117	DTMF Receiver IC MT8870 Tester	50784
118	Pulse Generator	40097
119	Infrared Remote Control Timer	47108
120	Clap Switch	76568
121	Multi-Switch Doorbell With Indicators	26555
122	Song Number Display	35894
123	Lead-Acid Battery Charger With Voltage Analyser	52997
124	Electronic Security System	99320
125	Three-Colour Display Using Bicolour LEDs	43813
126	Ultra-Bright LED Lamp	64836
127	Computerised Universal Timer	36322
128	Number Guessing Game	31373
129	PC-Based Oscilloscope	208747
130	Intruder Radio Alert System	45076
131	Flashing Beacon	40756
132	Knock Alarm	55699
133	Automated Traffic Signal Controller	64411
134	Infrared Toy Car Motor Controller	173326
135	Mains Manager	32509
136	Crystal-Controlled Time-Base Generator	25428
137	Mains Operated Christmas Star	27668
138	Music On-Hold For Telephones	34463
139	Solidstate Switch For DC-Operated Gadgets	26080
140	Ding-Dong Bell	58944
141	IR Remote Switch	84651
142	Shortwave Transmitter	40980
143	FM Booster	84808
144	Laser Torch-Based Voice Transmitter And Receiver	66821
145	Mobile Phone Battery Charger	57117
146	Fastest Finger First Indicator	42985
147	Condenser Mic Audio Amplifier	56457
148	DarkRoom Timer	34293
149	Speller Effect Sign Display	28813
150	Stereo Tape Head Preamplifier For PC Sound Card	34424
151	A Hierarchical Priority Encoder	21547
152	Digital Mains Voltage Indicator	38913
153	Water-Level Controller	69582
154	Invisible Broken Wire Detector	62444
155	Anti-Theft Security For Car Audios	40831
156	Simple Telephone Ring Tone Generator	40277
157	Versatile Zener Diode Tester	32303
158	DTMF Proximity Detector	57264
159	Under-/Over-Voltage Beep for Manual Stabiliser	24284
160	15-Step Digital Power Supply	55267
161	Auto Shut-off For Cassette Players And Amplifiers	25988
162	House Security System	96684
163	Generation Of 1-Sec. Pulses Spaced 5-Sec. Apart	19865
164	9-Line Telephone Sharer	56524
165	Musical ‘Touch’ Bell	48846
166	Automatic Heat Detector	45369
167	Single Phase Electronic Starter	24903
168	Precision Amplifier With Digital Control	34481
169	Precision Attenuator With Digital Control	21319
170	Infrared Electronic Shooting Game	10320
171	Telephone Ringer Using Timer ICs	28142
172	Blown Fuse Indicator	25573
173	Automatic Speed-Controller For Fans and Coolers	40828
174	2-Line Intercom-Cum-Telephone Line Changeover Circuit	30115
175	Low-Cost PCO Billing Meter	32068
176	Telephone Line Based Audio Muting And Light-On Circuit	20236
177	Power-Supply Failure Alarm	37691
178	Add-On Stereo Channel Selector	21360
179	Parallel Telephones With Secrecy	27720
180	Telephone Number Display	54892
181	Luggage Security System	34881
182	Precision Digital AC Power Controller	28143
183	Phone BroadCaster	26963
184	Telephone Call Meter Using Calculator And COB	25783
185	Telephone Conversation Recorder	33590
186	Universal High-Resistance Voltmeter	19222
187	Protection For Your Electrical Appliances	24670
188	Simple Code Lock	42577
189	Time Switch	27596
190	Digital Speedometer	24629
191	Long-Range FM Transmitter	173789
192	Self-Switching Power Supply	25176
193	Electrical Equipment Control Using PC	68478
194	Teleremote Control	41349
195	Low-Cost Transistorised Intercom	29077
196	Charge Monitor For 12V Rechargeable Lead-Acid Battery	49707
197	Cordless Phone Backup	24773
198	Sleep-Switch Cum Wake-up Timer	20118
199	Simple Analogue To Digital Converter	28171
200	Dual-Channel Digital Volume Control	27912
201	Infrared Cordless Headphone	59234
202	Magnetic Proximity Switch	21813
203	Simple Low-Cost Digital Code Lock	34424
204	Ultra Low Drop Linear Regulator	11567
205	Simple Sensitive Remote Control Tester	13267
206	Electronic Scoring Game	16656
207	Tiny Dew Sensor	17391
208	Electronic Jam	39200
209	Precision 1Hz Clock Generator Using Chip-On-Board	13464
210	Digital Switching System	23873
211	40-Metre Direct Conversion Receiver	21908
212	Frequency Measurements Using PC	24330
213	Contactless AC Mains Voltage Detector	13999
214	PC-Based 7-Segment Rolling Display	22154
215	Electronic Card-Lock System	44869
216	Miniature Strobe Light	19634
217	Automatic Dual-Output Display	13556
218	CD-ROM Drive As Digital-Audio CD-Player	36958
219	Clap Remote	20866
220	Wiper Speed Controller	17363
221	Water Level Indicator With Alarm	32101
222	IC Controlled Emergency Light With Charger	36106
223	Auto Reset Over/Under Voltage Cut-Out	7235
224	Smart Phone Light	13045
225	Automatic Emergency Light	20240
226	Telecom Headset	12496
227	Automatic Room Power Control	16350
228	Handy Zener Diode Tester	8912
229	Telephone Line Vigilant	9257
230	High and Low Voltage Cutout With Delay and Melody	7328
231	Colour Sensor	21069
232	Running Message Display	18249
233	Low Current, High Voltage Power Supply	9865
234	Audio-Visual Extra Ringer For Phone	5697
235	Solidstate Auto Power-Off/On Mains Failure	5653
236	7MHz CW/AM QRP Transmitter	7599
237	Intelligent Switch	16211
238	Fluid Level Detector	11870
239	Programmable Door-Bell With Flashing LEDs	8735
240	Clap Switch	12844
241	Computerised Morse Code Generator/Transmitter	6148
242	Accurate Electronic Stop-Watch	7199
243	Magic Lights	17976
244	Digital Dice With Numeric Display	9291
245	Sensitive Temperature Switch	9742
246	Automatic Temperature Controlled Fan	14228
247	Watch-Dog for Telephones	9192
248	FM Transmitter For Channel Changer	15906
249	UPS For Cordless Telephones	16515
250	Touch-Sensitive Musical Bell With Timer	6787
251	Programmable LED Indicator	10404
252	Economical Pump Controller	8842
253	Fire Alarm	16119
254	Short Wave AM Transmitter	10508
255	Automatic Emergency Torch	9828
256	Ramp Controlled Light	6564
257	Simple Intercom Circuit	12911
258	Tank Overflow Preventer	10721
259	33-Volt Tunning Voltage	7543
260	Appliance Timer	8476
261	Electronic Code Lock	16046
262	Flashing Brakelight	8037
263	IR Remote Control	19627
264	Car Anti-Theft Wireless Alarm	16267
265	Divide-By-N Counter Realisation Using ICs CD4033 And CD4017	8850
266	Soft Musical Telephone Ringer	6022
267	Low Cost Transistorised Inverter	13875
268	Automatic Telephone Answering Machine	12608
269	Hourly Chime Function Generator	6413
270	Programmable Priority Time Switch	7660
271	Digital Volume Control	15381
272	Extension Phone Switcher	6124
273	Battery Opeated High Voltage Source	9990
274	Handy Telephone Receiver	9910
275	A Highly Efficient DC Lamp Dimmer	7841
276	Low Cost Automatic Gate LIght With A Musical Bell	8733
277	Automatic Switch For Audio Power Amplifier	8808
278	Capacitance Bridge	9036
279	Darkness Controlled Light Switch	13507
280	AF/RF Signal Tracer	11013
281	Automatic Temperature Controller	13502
282	Simple Logic Probe	7121
283	Telephone Amplifier	8359
284	Ready -To-Use Object Counter	8451
285	Four-In-One Burglar Alarm	9562
286	Telephone Call Counter	10645
287	Water Level Controller Using 3-Phase Starter	9520
288	Running Lights Effect	10631
289	Programmable Musical Bell	6533
290	Solidstate Relay with Under/Over Voltage Protection	6071
291	Adjustable Dancing Lights	6511
292	Ultrasonic Switch	9529
293	Off-Line Telephone Tester	4937
294	Dancing Lights	10386
295	Versatile Variable Duration Digital Timer	3580
296	Programmable 8-Digit Code Lock	6997
297	Add Auto Start To Generators	4043
298	Sound Controlled Flip-Flop	4403
299	Tacho for Microprocessor Based Drives	4314
300	Low Cost Electronic Clock	7750