Copyright: 1996 - 2024
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
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My Hobby Website:
Cell Phone Jammer Circuit Design is so simple - RF Cafe Forums
RF Cafe Forums closed its virtual doors in 2012 mainly due to other social media
platforms dominating public commenting venues. RF Cafe Forums began sometime around
August of 2003 and was quite well-attended for many years. By 2010, Facebook and
Twitter were overwhelmingly dominating online personal interaction, and RF Cafe
Forums activity dropped off precipitously. If the folks at
phpBB would release a version with integrated
sign-in from the major social media platforms, I would resurrect the RF Cafe Forums,
but until then it is probably not worth the effort. Regardless, there are still
lots of great posts in the archive that ware worth looking at.
Below are the old forum threads, including responses to the original posts.
|-- Amateur Radio
Gripes & Humor
-- CAE, CAD, &
Test & Measurement
Post subject: Cell Phone Jammer Circuit Design is so
simple Posted: Thu Sep 22, 2005 5:53 am
Wed Sep 21, 2005 3:40 am
I would like to explain the design of cell phone jammer.Cell phone
is actuelly a two way radio i:e we can send and receive signals of different
frequencies.The all you need to design is:
VCO (Voltage Controlled
1650 – 2050 MHz
TL074 Quad Opamp
9 Volt Power Supply
Here you will generate the radio
waves using VCO and apply that output signal to operational amplifier
to amplify that signal.A voltage regulator is used which controls the
operation of oscillator circuit and 9v power supply is used to operate
our final circuit.When the waves are generated and amplified,you will
need a small antenna which transmits these waves in the range of 60-80
meters.When any one enters in this range and he receives a call whose
frequency is inbetween 1650-2050 MHZ,our generated signal and origional
signal collide and cancle power of eachother. So no input is detected
by cellular. No service message is always there on that cellular.
NOTE:You can also block any FM radio but you need an oscillator which
generates waves in range of 88-108 MHZ.
Design It and Enjoy
Post subject: Posted: Thu Sep 22, 2005 9:35 am
Joined: Mon Jul 18, 2005 4:31 pm
Anybody else think that Naveed is now on the list?
Post subject: Posted: Thu Sep 22, 2005 11:49
But at what point do we soak our hands in acid?
Post subject: Posted: Thu Sep 22, 2005 12:35 pm
Joined: Wed Aug 20, 2003 11:47 am
Location: Santa Barbara, CA
Wow, I didn't know a TL074 opamp
could be used in the 1650-2050MHz band!! Thats one good opamp!!