535 Threads found on edaboard.com: Fm Circuit
hi every body
i was simulating an FM circuit
i have a problem in the antenna
shall i make it a load 75ohm
or i shall not but it in the design
i use orcad in simulating
but when i but the antenna as a load the oscillator dies
RF, Microwave, Antennas and Optics :: 02.03.2007 14:29 :: mr_byte31 :: Replies: 5 :: Views: 964
This paper should help you through the design process.
Hobby Circuits and Small Projects Problems :: 21.08.2013 12:22 :: E-design :: Replies: 20 :: Views: 980
In typical FM transmitter topology, the modulating signal directly modulate the VCO and the VCO are locked by a PLL. The DC component is 'absorbed' by the PLL. So it is always an AC-coupling FM. Any body know how to make a DC-coupling FM circuit? Or any chipset to do it?
RF, Microwave, Antennas and Optics :: 07.01.2005 03:16 :: wpsch :: Replies: 0 :: Views: 512
Look there * by t
RF, Microwave, Antennas and Optics :: 02.02.2005 13:00 :: papyaki :: Replies: 6 :: Views: 1267
in fm transmitter circuit , i found aproblem in it
as one of it's componants is 2 coils each one 0.001?H
but there is no IF
i sold the 2 coils and connect the circuit but it didn't work
i can't solve this problem
if any body know about the matter plz tell me
Hobby Circuits and Small Projects Problems :: 31.08.2006 17:36 :: new life :: Replies: 9 :: Views: 2802
Do they still use a piezo mic in India? I haven't seen one for about 45 years. An inexpensive biased electret mic should be used instead.
My FM transmitter circuit uses a 2N3904 transistor as its oscillator and another as its RF amp that isolates the antenna from the oscillator so that the frequency doesn't change when something moves toward and
Hobby Circuits and Small Projects Problems :: 27.07.2010 22:53 :: Audioguru :: Replies: 5 :: Views: 2047
Hello everybody, a need to produce a Digital FM demodulation in matlab but i am a bit confuss, because i have always studied that fm is an analog modulation so why digital?
how can implement the digital fm demodulation?
where can i find the code?
thank you very much
Digital communication :: 17.06.2010 10:45 :: sirdivi :: Replies: 2 :: Views: 3093
i want ask you about ...
1. how i can transmit my message in narrow bandwidth ??
2. how i can reduce a noise " i want clear sound " ??
for example circuit is working ,, if you choose C3 and L1 Properly
RF, Microwave, Antennas and Optics :: 31.07.2010 19:06 :: jaloud :: Replies: 3 :: Views: 1492
I wish to design a FM circuit as follows
1) two frequencies that I use are 1 KH and 250 Hz
The FM circuit will have a output containing 750 Hz, 1kHz and 1.25 KHz
2) A circuit that can extract the 750 Hz signal
3) Another circuit extracting the 1.25 Khz signal
Please help me out.
Thanks and (...)
Analog Circuit Design :: 23.08.2010 10:41 :: pratapkollu :: Replies: 4 :: Views: 1443
I'm a newbie with multisim and was trying to see a FM circuit posted by E-design. I got a curios behavior . The circuit alone doesn't oscillate until I add a Spectrum analyzer instrument and a probe (probe1). Taking out the SA the circuit oscillate around KHZ .
I really don't understand what happen.
Here is the circuit
Analog Circuit Design :: 11.09.2010 16:15 :: Flying_carlos :: Replies: 5 :: Views: 2557
Please help me! compute frequency and transmitting power of circuit
Analog Circuit Design :: 10.11.2010 06:14 :: thanhtung_bk52 :: Replies: 0 :: Views: 330
I need a simple circuit schematic of two analog modulators. Modulator FM and AM. I have to perform simulation of this in pspice. I search on web any schematics with values of elements, but I can't found working.
Anybody help me?
Sorry for my english.
Thx for help, othername.
Analog Circuit Design :: 02.02.2013 09:18 :: othername :: Replies: 3 :: Views: 656
Hi, I'm new here, I have a little problem, I'll be grateful for the help. It happens that I want to modify the circuit of an FM audio transmitter, so that instead of transmitting audio can transmit a signal to turn off or turn on a switch, and the switch on and off an LED, the idea is to communicate using Morse code using the FM frequency. What co
Digital Signal Processing :: 17.03.2013 19:13 :: StrawberryBro :: Replies: 3 :: Views: 346
TW523, 2way x10 module datasheet uploaded to FM, directory arturt134. This is version for 110V/60Hz. For 220V/50Hz try to search
Professional Hardware and Electronics Design :: 24.08.2001 05:27 :: arturt134 :: Replies: 9 :: Views: 3467
You have TDA 7010T for FM receiver,
and SA 604AD for FI FM.
I know them by name, it is everything.
If that can be useful for you...
Regards and Bonne journée :smile:
Professional Hardware and Electronics Design :: 05.05.2002 09:47 :: nidala5 :: Replies: 3 :: Views: 1002
I'm designing a system in FM, in 1.000 Mhz to 2.000 Mhz (yes Mhz 1000Khz), to modulate audio.
In first time, i used the VCO of a CD4046, so I connect a potentiomenter to it in a way to set the frecuency like this:
|..4046..|---->/--------| |------ Audio in
Professional Hardware and Electronics Design :: 28.06.2002 13:03 :: penrico :: Replies: 3 :: Views: 1199
I have build a FM radio using STR TEA5757, according Philips Application note AN99041.
I have a problem with FM VCO alignment. If you align VCO coil the tunning voltage should change between 0.8V(88MHz) and 1.9V(108MHz), but in my PCB this isn't happen.
If I align my VCO coil the tunning voltage is constant in all the FM band.
RF, Microwave, Antennas and Optics :: 12.09.2002 04:40 :: tipet20002000 :: Replies: 10 :: Views: 6465
I want to make UHF & FM antenna booster. Both will be seperate circuits. Please guide me where can i get good schematics\circuits.
RF, Microwave, Antennas and Optics :: 26.12.2002 12:21 :: palesha :: Replies: 14 :: Views: 35676
please introduce the manufacture of 50-100W fm UHF transmitter/receiver
modules that have high quality.
or if you a circuit sch about this I need it.
It should have the capability to change its frequency by embedded software.
RF, Microwave, Antennas and Optics :: 25.02.2003 16:48 :: 7rots51 :: Replies: 2 :: Views: 1313
for a low/medium power FM radio station
preferably a stereo one
RF, Microwave, Antennas and Optics :: 16.04.2003 18:21 :: Basil :: Replies: 2 :: Views: 1471
I am looking for a hardware clockrecovery circuit that is able to derive the clock from a 300 kbps datastream. The datastream is the output of a FM detector.
Anyone with expierence in this field?
Professional Hardware and Electronics Design :: 25.06.2003 08:37 :: beagle :: Replies: 2 :: Views: 979
Seeking to construct circuit transmitter fm estereo pci with modules rf
of 1w at 5w for my music mp3
Something of this
Professional Hardware and Electronics Design :: 02.08.2003 21:34 :: tekton :: Replies: 0 :: Views: 761
Also RFM ( ) has single-chip solutions for your problem.
Hobby Circuits and Small Projects Problems :: 10.09.2003 10:35 :: mr_ghz :: Replies: 6 :: Views: 3766
I need to modulate an audio signal for transmitting by optica fiber. Somebody knows some circuit to modulate and demodulate audio in FM, PWM...
Hobby Circuits and Small Projects Problems :: 10.12.2003 14:37 :: kkdelabaca :: Replies: 2 :: Views: 1357
In fact the coil is part of the PCB.
Here is the pcb layout
Hobby Circuits and Small Projects Problems :: 19.12.2003 14:44 :: SphinX :: Replies: 2 :: Views: 2703
i am looking for circuits which can capture sound very clearly even at very low volume - eg: a very soft sounds of birds at a distance of 3-5 meters
very low volume amplifier which can capture and amplify soft sounds clearly with this a fm module will also be of help
please help i am in need of one very soon
thanking you i
Hobby Circuits and Small Projects Problems :: 19.01.2004 19:07 :: meetmepal :: Replies: 2 :: Views: 1561
which standard do you want ?
RF, Microwave, Antennas and Optics :: 01.04.2004 21:33 :: yykk :: Replies: 3 :: Views: 1187
Ya, thanx for all ur replies.
I want to transmit digital 8-bit serial data through FM.
For this i will use D/A Convertor at transmitter end & A/D Convertor at receiver's end.
The range could be Some within 10 metres. and plz tell me if i want to extend the range should i change the carrier Frequency or what else..?
With Best reg
RF, Microwave, Antennas and Optics :: 13.04.2004 08:40 :: mystic_matrix :: Replies: 6 :: Views: 2183
there is maxim max2606, which is a simple FM (75-150Mhz) vco, but it's not a pll...
Hobby Circuits and Small Projects Problems :: 24.04.2004 04:04 :: Kripton2035 :: Replies: 11 :: Views: 6199
Im trying one transistor FM modulator with demo version of MicroCAP.
The circuit makes two functions at the same time one is osc. The other is to amplify audio signal. This kind of a two function circuit had been named as reflex circuit. Amplified audio signal changes the voltage-dependent-capacitor between the collector and (...)
Analog Circuit Design :: 05.05.2004 05:42 :: atmaca :: Replies: 2 :: Views: 2257
i am in need of single chip fm demodulator IC.
and associated circuit to design the FM receiver in 88 - 108MHz
thanks in advance.
Hobby Circuits and Small Projects Problems :: 17.05.2004 05:14 :: jsp :: Replies: 4 :: Views: 4829
RF, Microwave, Antennas and Optics :: 05.05.2005 03:09 :: vfone :: Replies: 3 :: Views: 3287
I would like to implement FM radio chip with TEA5757 for a portable system with a fixed base charger.
My question is regarding how to implement the antenna.
Is it possible to use an inside-the-device antenna? I mean, no external wires.
Is it possible to integrate the inside antenna with and external one in the fixe
RF, Microwave, Antennas and Optics :: 02.07.2004 16:52 :: martingn :: Replies: 3 :: Views: 2013
If You are lucky enough, You can get an MC2833. That is an FM transmitter
Professional Hardware and Electronics Design :: 22.07.2004 09:42 :: probert :: Replies: 19 :: Views: 18282
i hav made my first bot and want to make it wireless.i hav a PIC controller board for controlling motors and the bot is controlled frm a computer.
now for making wireless i hav 2 use some RF modules but i cannot afford i was thinking of using FM modules because that is is it possible 2 control bot frm a pc usin FM?can an
Robotics and Automatics Forum :: 04.09.2004 16:38 :: mexx :: Replies: 21 :: Views: 3660
Are you looking for a receiver RF amplifier, or a transmitter linear amp?
What freqency band are you trying to amplify? Is it for FM broadcast frequencies, and if it is - what country?
RF, Microwave, Antennas and Optics :: 22.09.2004 18:41 :: House_Cat :: Replies: 2 :: Views: 2700
Have you considered a single chip transceiver? One manufactuer's data with a schematic can be found at:
You could also combine a simple FM transmitter, such as one found at:
With a simple FM reciever, such as found at:
Professional Hardware and Electronics Design :: 03.10.2004 13:10 :: House_Cat :: Replies: 2 :: Views: 2025
Here is an example:
RF, Microwave, Antennas and Optics :: 13.10.2004 15:12 :: vfone :: Replies: 2 :: Views: 1179
Please elaborate ? what do whant to do :
1) use the pic to control a PLL ? - search google for PLL + PIC
you will find many circuit
2) Use the pic to crate the FM signal (DDS alike )- to slow to do the job
Microcontrollers :: 16.10.2004 09:59 :: bobcat1 :: Replies: 5 :: Views: 1680
Assalam O Alekum !
Following attachment contains
Explanation with Figures
A circuit diagram for FM Modulator
Several methods of Demodulation
circuit diagrams of different Modulators
Mathematical as well as theoretical explanation of each circuit
Interference in FM
I hope (...)
Hobby Circuits and Small Projects Problems :: 14.12.2004 03:25 :: Hamidzia :: Replies: 51 :: Views: 30990
This PLL circuit can be easily used to demodulate FM signal with deviations in the range of several MHz; no setup here.
Deviation has to be determined at the modulator end by adjusting the level of the signal that will be Frequency Modulated (kHz or MHz / Volt)..
RF, Microwave, Antennas and Optics :: 02.02.2005 02:02 :: IanP :: Replies: 1 :: Views: 1249
I am constructing FM transmitter to work in radius of 100 feet. For the frequency multiplier section I used BF494 with voltage divider bias (R1=15k, R2 = 4.7k). The colector has LC tank circuit with 4.7pF capaitor between collector and emitter. Varactor diode is used for frequecy modulation which is coupled to the tank circuit using 22p
RF, Microwave, Antennas and Optics :: 06.02.2005 11:50 :: CMOS :: Replies: 4 :: Views: 1460
the block diagram and pin configuration of 4046 in FM modulator/demodulator exist in its data sheet.you can download its data sheet and see its block diagram.
Analog IC Design and Layout :: 07.02.2005 13:35 :: mehdi :: Replies: 5 :: Views: 12590
Examples of FM microphone transmitters:
Electronic Elementary Questions :: 27.02.2005 19:10 :: IanP :: Replies: 2 :: Views: 1240
dear sir ,i am an engineering student . i have to do a project wherein i have to design a fm transmitter and get the dtmf tones modulated at 10.75 mhz , here 10.75 is the carrier frequency and i have to get the dtmf tones modulated at this frequency . i have tried lots of ccts but getting the frequency modulation done at HF range is still a problem
Professional Hardware and Electronics Design :: 16.03.2005 12:20 :: satishmalik :: Replies: 3 :: Views: 1536
For FM you do not actually need AGC. Limiters in the IF strip are usually used. There is the rare case when you need to reduce the gain befor the first mixer but this is rarely done.
The Amateur Radio Handbooks by the RSGB and ARRL are full of information for radio electronic designs. These are frequently available at city libraries.
Analog Circuit Design :: 18.03.2005 11:27 :: flatulent :: Replies: 9 :: Views: 1450
I m working on remote controlled car where I requires FM modulator & Demodulator IC. Can anybody suggest IC no's that requires less hardware or a ckt that can be used in remote controlled vehicle.
Electronic Elementary Questions :: 30.03.2005 09:29 :: smartshashi :: Replies: 3 :: Views: 2080
The book is very good, but i just want to make a simple CDMA transmitter receiver demonstration for my project and there is no restriction to comly with the stadards. it could use the frequencies for fm radio. the data to be transmitted is sensor temperature ineed 3 or 4 transmitters and one receiver. could any one help.
Hobby Circuits and Small Projects Problems :: 25.04.2005 18:12 :: as_518 :: Replies: 2 :: Views: 775
Im trying to design an FM transmitter to operate at a higher frequency than that of fm radio range. I found some circuits on wireless mic. Is it possible to tune these circuits to about 900 Mhz without compensating the audio quality? Are there IC's able to transmit within this range?
Analog Circuit Design :: 04.05.2005 22:42 :: hermin :: Replies: 2 :: Views: 652
My FM reciever has sensitivity about -80 dBm But I need sensitivity at -100 dbm or more.
How can I tuning? Which part of circuit can be tuning? Please .......Thank you very much :-)
RF, Microwave, Antennas and Optics :: 10.05.2005 04:48 :: heab :: Replies: 4 :: Views: 810