Waves Converter

[Michael-love-electronics]

We know that the microwaves start from 330MHz,...
now,..How to change from microwaves to FM radio waves or How to have input of 330MHz and get output of 100MHz.??????

[Chris Smith]

Microwaves come in AM and FM which simply refere to how the signal is coded/ decoded within the RF energy.

[Michael-love-electronics]

Thsnks for replying but,..I mean by the microwaves here the high frequecies above 400MHz which is not RF,...Or in another word the cell phones frequencies.
How to convert from cell phones freq. to RF.??????

[Chris Smith]

Its all RF, Sorry!<p>I did forget Square wave which still comes in AM, FM, and digital. <p>Microwave RF /both AM/FM was used for decades, but what your trying to say is probably digital signals, which in some cases still contain side bands of Am or Fm.

[russlk]

You need a mixer and a local oscillator. Feed the 330mHz and 230mHz oscillator into the mixer and get 100mHz out. It is not that simple, you need the right amplitude and tuned circuits.

[Michael-love-electronics]

Thanks very much for replying,.....
would you mind to send me more details as sometimes the cell phone tones drive me mad so I thought that if I made a device that is much more sensitive than any other mobile, the device can receive the waves before the cell does and then change it RF so the cell phones will not work as the reqired freq. is missing......(hope you understand my words,..difficult to explain)<p>Thanks again very much

[Externet]

You should had said that from day one.<p>Look here:<p>http://www.phonejammer.com <p>Enjoy,
Miguel

[Michael-love-electronics]

Dear Miguel,...<p>Thanks thousand times for this help, although the I can't find the circuit but this site had proved that what I was thinking of is right.
do you have the circuit.????????
Thanks again very very very much <p>[ December 02, 2002: Message edited by: Michael Wahid ]</p>

[Externet]

I do not have the circuit. But building it may be more headache, time and expense than buying one of the devices shown there. The biggest hurdle is typically a neat housing.
I have seen them advertised for about $70 somewhere.
Click on the other links at the bottom left of that page.<p>Miguel

[Michael-love-electronics]

Thanks for replying but I'm dieing to know everything about that jammers:
1st: jammers send RF that blocks the cell phones and prevent transmitting & receiving.....HOW.????
2nd: I read that a jammer sends "+20dBm(Min)" that what I read,..so what does it mean by dBm.???
does it mean decible.???can I convert it to freq.??? <p>Thanks again <p>[ December 03, 2002: Message edited by: Michael Wahid ]</p>

[bwts]

Yes it does stand for decibel its probably refering to the power output from the jammer (dont know what the m at the end is tho) anyway a +20db signal is probably enough to drown out any signal trying to get to mobile phone. (just guessing here)<p>B

[Bernius1]

Remember, if you're broadcasting a signal, and it's over several watts, the FCC may show up at
your door, or your neighbors' radios may receive
your remodulated 100Mhz signal. Big Grey area.
Theoretically, a superhet local osc. half way
between the desired freq.'s will allow the conversion without demod/remod. (just re-amping
the lower sideband).PLL/IF/VCO/AMP is the
alternative. OOH FAH !!!!

[russlk]

dBm means dB relative to 1 milliwatt, so +20dBm is 100 milliwatts.

[haklesup]

Seems to me that most digital phones would simply switch over to Analog mode if it couldn't lock onto a Digital tower. You would have the honor of draining their batteries faster though. Perhaps pulsing the jammer output would cause a dropped call as fast as it came in.

[Michael-love-electronics]

Thanks very much to All of you for this help, I really appreciate that but,......
How this Radio frequency can jam the cell phone.?
Also, How can I convert dB to Hz (formula plz).???<p>That's all for now and thanks in advance<p>[ December 05, 2002: Message edited by: Michael Wahid ]</p>