FM Transmitter with PLL
This
simple AM circuit uses a 561B. There's no inductance/capacitance tuning
circuit. The 365 pF capacitor connected between pins 2 and 3 does all
the tuning. The circuit needs a good outside antenna and a solid ground.
And if you want to further improve operation, stick a broadband
amplifier in front of the receiver.
..
The
µA2240 consists of four basic circuit elements: (1) a time-base
oscillator, (2) an eight-bit counter, (3) a control flip-flop, and (4) a
voltage regulator. The basic frequency of the time-base oscillator
(TBO) is set by the external time constant determined by the values of
R1 and Cl (1R1C1 = 2 kHz). The open-collector output of the TBO is
connected to the regulator output via a 20 k ohm.....
One
of the most interesting projects to work with is that of a synthesizer
that can accurately gnerate desired frequencies. This synthesizer uses
just three CMOS chips and one PNP transistor. It is a fact that the
transistor may be the hardest component to get in some parts of the
world!! The synthesizer will generate a 3:1 frequency range anywhere
from 300Hz to 4,000,000Hz (4MHz). Using the.....
In
order to simplify the transmitter design, we've used the new pll circuit
from Motorola :the MC145170. This PLL includes the prescaler and a
serial standard bus called SPI. We advise to use the P2 version that
fixes some init issues during the Power Up. This PLL circuit is
definitely smaller than the old one, consequently we've added on the
radio board, the power control circuit that allows.....
This
new FM transmitter is very easy to make and doesn't need any RF tuning.
First of all ,we have used an integrated VCO: The POS150 from
Mini-circuits. This excellent RF circuit covers all the FM Band in a
voltage range of 4V to 8V. The Kvco factor is very stable all over the
FM band, consequently, we have applied the AF signal directly on the
control voltage line coming from the PLL. A 4dB.....
The
quartz QZ1 of the preceding receivers which set the work frequency is
not on the market any more. It is replaced
by a locking phase loop allowing the free choice of an unspecified
frequency on the band used, either the 41, or the 72 MHz. The step
between channels is 5 kHz, giving us 101 frequencies in 72 MHz and 41 in
41 MHz. In practice, the RX19 " scans " on the 2 frequencies chosen
by.....
This
transmitter is PLL controlled and the frequency is very stable and can
be programmed digitally. The transmitter will work from 88 to 108 MHz
and the output power is up to 500mW. With minor changes the frequency
can be set from 50 to 150 MHz. The main oscillator is based around the
transistor T1. This oscillator is called Colpitts oscillator and it is
voltage controlled to achieve FM.....
The
main oscillator is printed in blue and is voltage controlled.
In this construction the VCO range is 88 to 108 MHz. As you can see from
the blue arrows, some energy goes to an amplifier and some energy goes
to the PLL unit. You can also see that the PLL can control the frequency
of the VCO. What the PLL do is that it compare the VCO frequency with
the reference frequency (which is very.....
The MC13136 circuit is not easy to find so I have replaced it with a new receiver circuit called SA615.
This is a basic FM receiver with very good performance and sensitivity.
In my super receiver I used a DDS to fine tune the receiver, but in this project
I replaced it with a PLL synthesizer. I have decided the oscillator frequency of the FM receiver to be 38.9MHz.
See figure at right......
The
transmitter includes RDS/SCA input and Audio/MPX input with optional
preemphasis. It can be used with or without stereo encoder. Tuning over
the FM band is provided by two buttons that control dual-speed PLL. The
transmitter can work also without the LCD display. Some experience with
building devices of this kind are highly recommended. After complete
parts placement: Check that there are.....
Here's
PLL FM transmitter circuit from china. This circuit uses the familiar
2SC1971 for final power amplifier stage. The PLL controller of the FM
transmitter use SAA1057 and PIC16F628 (download HEX file)...
This
is the latest BH1417 FM Transmitter design from RHOM that includes a
lot of features in one small package. It comes with pre-emphasis,
limiter so that the music can be transmitted at the same audio level,
stereo encoder for stereo transmission, low pass filter that blocks any
audio signals above 15KHz to prevent any RF interference, PLL circuit
that provides rock solid frequency.....
The
circuit is a divider by 64 used in many RF applications like as
satellite receiver, digital tuners, frequency counters, PLL, etc. The
heart of circuit is an IC named SAB6456, but you can use SDA2101 or
other equivalent chips. Each output is NOT of the other...
Here
is the latest and greatly improved TX200 VFO/VCO FM transmitter. The
most versatile transmitter to date that can be turned into high fidelity
stereo PLL based 200mW FM transmitter. It is a perfect circuit for
transmitting your music around the house and yard. TX200 uses only two
coils; one in the oscillator and the other one in the 200mW VHF
amplifier so it should be fairly easy for anyone.....
This PLL can operate over a wide frequency range, not just
1 or 2 octaves but over 1 or 2 or 3 decades. It naturally
provides a voltage output which responds quickly to frequency
changes, yet does not have any inherent ripple.
Thus, it can be used as a frequency-to-voltage (F-to-V)
converter..
The
circuit in Figure 1 stems from a radio-controlled modeling application,
which requires a voltage proportional to the width of the incoming servo
pulses. The circuit is optimized for a positive-going pulse width of 1
to 2 msec, repeating at intervals of approximately 17 msec. The output
produces a voltage of 0.95V for a 1-msec pulse to 2.25V for a 2-msec
pulse. The circuit operates similarly.....
The TDA1591 is a monolithic bipolar integrated circuit
providing the stereo decoder function and noise blanking
for FM car radio applications...
The IRPLLNR2 is a high efficiency, high power factor, fixed output
electronic ballast designed for driving rapid start fluorescent lamp types. The design contains an EMI
filter, active power factor correction and a ballast control circuit using the IR21571. This demo board is
intended to ease the evaluation of the IR21571 Ballast Control IC, demonstrate PCB layout techniques
and serve as an.....
The IRPLLNR1 is a high efficiency, high
power factor, non-dimmable electronic ballast
designed for linear fluorescent lamp types.
The design contains an active power factor
correction circuit for universal voltage input
and a ballast control circuit using the IR2153
for controlling the lamp. Other features
include EMI filtering, transient protection and
lamp fault protection...
Many
Video Operated Relay (VOR) circuits have been published in recent years
for use in connection with ATV repeater controllers or automatic
videotape logging systems. Unfortunately, many of these circuits fail to
properly detect certain video signals depending on their
signal-to-noise ratio or their picture content. Most designs rely on
using an LM567 phase locked loop (PLL) tone decoder chip.....
This
simple AM circuit uses a 561B. There's no inductance/capacitance tuning
circuit. The 365 pF capacitor connected between pins 2 and 3 does all
the tuning. The circuit needs a good outside antenna and a solid ground.
And if you want to further improve operation, stick a broadband
amplifier in front of the receiver.
..
The
µA2240 consists of four basic circuit elements: (1) a time-base
oscillator, (2) an eight-bit counter, (3) a control flip-flop, and (4) a
voltage regulator. The basic frequency of the time-base oscillator
(TBO) is set by the external time constant determined by the values of
R1 and Cl (1R1C1 = 2 kHz). The open-collector output of the TBO is
connected to the regulator output via a 20 k ohm.....
One
of the most interesting projects to work with is that of a synthesizer
that can accurately gnerate desired frequencies. This synthesizer uses
just three CMOS chips and one PNP transistor. It is a fact that the
transistor may be the hardest component to get in some parts of the
world!! The synthesizer will generate a 3:1 frequency range anywhere
from 300Hz to 4,000,000Hz (4MHz). Using the.....
In
order to simplify the transmitter design, we've used the new pll circuit
from Motorola :the MC145170. This PLL includes the prescaler and a
serial standard bus called SPI. We advise to use the P2 version that
fixes some init issues during the Power Up. This PLL circuit is
definitely smaller than the old one, consequently we've added on the
radio board, the power control circuit that allows.....
This
new FM transmitter is very easy to make and doesn't need any RF tuning.
First of all ,we have used an integrated VCO: The POS150 from
Mini-circuits. This excellent RF circuit covers all the FM Band in a
voltage range of 4V to 8V. The Kvco factor is very stable all over the
FM band, consequently, we have applied the AF signal directly on the
control voltage line coming from the PLL. A 4dB.....
The
quartz QZ1 of the preceding receivers which set the work frequency is
not on the market any more. It is replaced
by a locking phase loop allowing the free choice of an unspecified
frequency on the band used, either the 41, or the 72 MHz. The step
between channels is 5 kHz, giving us 101 frequencies in 72 MHz and 41 in
41 MHz. In practice, the RX19 " scans " on the 2 frequencies chosen
by.....
This
transmitter is PLL controlled and the frequency is very stable and can
be programmed digitally. The transmitter will work from 88 to 108 MHz
and the output power is up to 500mW. With minor changes the frequency
can be set from 50 to 150 MHz. The main oscillator is based around the
transistor T1. This oscillator is called Colpitts oscillator and it is
voltage controlled to achieve FM.....
The
main oscillator is printed in blue and is voltage controlled.
In this construction the VCO range is 88 to 108 MHz. As you can see from
the blue arrows, some energy goes to an amplifier and some energy goes
to the PLL unit. You can also see that the PLL can control the frequency
of the VCO. What the PLL do is that it compare the VCO frequency with
the reference frequency (which is very.....
The MC13136 circuit is not easy to find so I have replaced it with a new receiver circuit called SA615.
This is a basic FM receiver with very good performance and sensitivity.
In my super receiver I used a DDS to fine tune the receiver, but in this project
I replaced it with a PLL synthesizer. I have decided the oscillator frequency of the FM receiver to be 38.9MHz.
See figure at right......
The
transmitter includes RDS/SCA input and Audio/MPX input with optional
preemphasis. It can be used with or without stereo encoder. Tuning over
the FM band is provided by two buttons that control dual-speed PLL. The
transmitter can work also without the LCD display. Some experience with
building devices of this kind are highly recommended. After complete
parts placement: Check that there are.....
Here's
PLL FM transmitter circuit from china. This circuit uses the familiar
2SC1971 for final power amplifier stage. The PLL controller of the FM
transmitter use SAA1057 and PIC16F628 (download HEX file)...
This
is the latest BH1417 FM Transmitter design from RHOM that includes a
lot of features in one small package. It comes with pre-emphasis,
limiter so that the music can be transmitted at the same audio level,
stereo encoder for stereo transmission, low pass filter that blocks any
audio signals above 15KHz to prevent any RF interference, PLL circuit
that provides rock solid frequency.....
